phenotype, genetics, pathogenesis and therapy - citeseerx

Brain (1997),120,1485–1508

I N V I T E D R E V I E W

Adrenoleukodystrophy: phenotype, genetics,pathogenesis and therapy*

Dedicated to the memory of Peter Moser

Hugo W. Moser

Kennedy Krieger Institute, Baltimore, USA Correspondence to: Hugo W. Moser, MD, Kennedy KriegerInstitute, 707 North Broadway, Baltimore, MD 21205 USA

SummaryThe occasion of the presentation of the eighth Gordon Holmes Yet I also feel a sense of sadness; the invitation to present the

lecture came from the late Anita Harding who, such a shortLecture left me feeling both honoured and awed, as a result ofmy review of the Selected Papers of Gordon Holmes (Phillips time before her illness, gave me personal guidance and

encouragement. In this lecture I endeavour to follow theCG: Selected Papers of Gordon Holmes, compiled and editedfor the Guarantors ofBrain. Oxford University Press, 1979), example of Gordon Holmes, namely the stepwise analysis of a

clinical problem, first by observation of the patient, followedkindly presented to me by the sponsors of the meeting. Thisvolume lists 174 publications produced over a 55-year period, by the application of techniques that can clarify it, leading to

new knowledge not only about the specific disorder, but alsoand contains reprints of contributions to neuroanatomy,neuropathology, and to disorders that affected the adrenal about the nervous system and human biology in general and,

it is to be hoped, to more effective therapy.cortex, the spinal cord, the cerebellum and the cerebral cortex.

Keywords: adrenoleukodystrophy; genetics; pathogenesis; phenotype; therapy

Abbreviations: ABC 5 ATP-binding cassette; AMN5 adrenomyeloneuropathy; CCER5 childhood cerebral form ofX-ALD; GTE 5 glyceryl trierucate (oil) ; GTO5 glyceryl trioleate (oil); TNF-α 5 tumour necrosis factor; VLCFA5 verylong chain fatty acids; VLCS5 very long chain fatty acid coenzyme-A synthase; X-ALD5 X-linked adrenoleukodystrophy

History of X-linked adrenoleukodystrophyThe history of adrenoleukodystrophy has taken many months later. An older brother had died of a similar illness

at 8.5 years. The post-mortem brain was studied by Paultwists and turns, and is marked by serendipity and surprises;Schilder (1913) and reported as the second of three casesit is likely that Haberfeld and Spieler (1910) describedthat he referred to as ‘encephalitis periaxialis diffusa,’the first patient with what is now called X-linkedcharacterized by diffuse involvement of the cerebraladrenoleukodystrophy (X-ALD). A previously normal boyhemispheres in children with severe loss of myelin, whichdeveloped disturbances in eye movement and vision atresembled multiple sclerosis because of the relativethe age of 6 years, became apathetic, and his schoolworkpreservation of axons and the accumulation of lymphocytes,deteriorated. Four months later his gait became spastic, andfat-laden phagocytes and glial cells (Schilder, 1912 andthis progressed to an inability to walk. He was hospitalized1924). The findings in the adrenal gland were not reported.at 7 years. Dark skin was noted, but otherwise not discussed.Subsequent studies have shown that what had been referredHe had a spastic paraparesis, severe apathy alternating withto as Schilder’s disease is heterogeneous and includes airritability, did not speak, and was incontinent. He died 8variety of entities in addition to X-ALD (Poser and vanBogaert, 1956; Poseret al., 1986). Siemerling and Creutzfeldt*Based on The Eighth Gordon Holmes Lecture given on June 27, 1994 at

the fourth European Neurological Society meeting in Barcelona (1923) reported on a patient with a similar clinical history

© Oxford University Press 1997

1486 H. W. Moseret al.

and neuropathological findings, except that involvement of and his associates (Lazoet al., 1988) and by Wanderset al.(1988) in Amsterdam pinpointed the VLCFA oxidation defectthe adrenal glands was documented. They named the disorder

‘Bronzekrankheit und Sklerosierende Encephalomyelitis to the impaired capacity to form their coenzyme-Aderivatives, leading to the plausible suggestion that the basic(diffuse sklerose)’. The name adrenoleukodystrophy was

coined by Blaw in 1970 (Blaw, 1970). defect involved the enzyme ‘very long chain fatty acidcoenzyme-A synthase’ (VLCS). Between 1978 and 1981 itDuring the period 1923–1974 there was considerable

speculation about the nature of X-ALD. The connection was shown in Baltimore and in Japan that X-ALD can bediagnosed reliably by demonstrating abnormally high levelsbetween the adrenal insufficiency and the demyelinative

process remained a puzzle. In their classic paper on the of VLCFA in cultured skin fibroblasts (Moseret al., 1980),red blood cells (Tsujiet al., 1981b) and plasma (Moserpathology of the demyelinative diseases, Adams and Kubic

(1952) placed multiple sclerosis and X-ALD in the sameet al., 1981). These non-invasive assays have led to theidentification of .3000 patients in the Kennedy Kriegergeneral category, but noted points of difference, such as the

contiguous involvement of large portions of the cerebral Institute diagnostic programme alone. The ultrastructural andbiochemical techniques also led to the recognition of milderhemispheres and the more severe degree of axon-cylinder

degeneration in X-ALD. In their discussion of pathogenetic X-ALD phenotypes in adults such as adrenomyeloneuropathy(AMN) by Budka et al. in Vienna in 1976 (Budkaet al.,mechanisms they noted the points of resemblance to

experimental allergic encephalomyelitis and suggested 1976) and Griffinet al. at the National Institutes of Healthin 1977 (Griffinet al., 1977). The era of dietary therapy wasautoimmune mechanisms. They discounted a metabolic

disorder or the direct action of an enzyme on the nervous ushered in by the demonstration of Kishimotoet al. (1980)that the abnormal VLCFA in the brain of an X-ALD patientsystem ‘because of the presence of the infiltrates of

inflammatory cells which are not seen in any of the known are, at least in part, of dietary origin and it was extended bythe observation that mono-unsaturated fatty acids, such asmetabolic disorders of the brain’. Even though there is now

no doubt that X-ALD results from a metabolic disorder, oleic and erucic acid, reduce their endogenous synthesis(Rizzo et al., 1986, 1989). The demonstration that bonerecent studies of the pathogenesis of the brain inflammatory

response in X-ALD indicate that the autoimmune mechanisms marrow-derived cells have the capacity to degrade VLCFAled to therapeutic trials of bone-marrow transplantationinvoked by Adams and Kubic (1952) are still highly pertinent.

Hoefnagelet al. (1962), Fanconiet al. (1963) and Blawet al. (Moseret al., 1984), which have proved successful in someinstances (Aubourget al., 1990; Krivit et al., 1995).(1964) noted that all patients had been male, and on the basis

of pedigree analysis, suggested that X-ALD is a genetically In 1981 the X-ALD gene was mapped to Xq28, theterminal segment of the long arm of the X-chromosomedetermined disorder with an X-linked mode of inheritance.

The major insight into the nature of X-ALD took place at (Migeonet al., 1981). Twelve years later Mosseret al. (1993)isolated the gene by positional cloning. It came as a surprisethe Albert Einstein College of Medicine in New York in

1973, 50 years after the initial description of the disease. It that the gene codes for a peroxisomal membrane protein,referred to as ALD protein, that belongs to the ATP-bindingwas the consequence of the collaboration between a

neurologist, Herbert Schaumburg, who had been attracted to cassette (ABC) protein family (Higgins, 1992). It has nohomology to VLCS, which has been isolated recentlythe study of X-ALD by E. P. Richardson at the Massachusetts

General Hospital, and an endocrine pathologist, James (Uchiyamaet al., 1996).Powers. Powers and Schaumburg (1973) demonstratedunusual striations in adrenocortical cells which were shown,by electron microscopy, to have a characteristic lamellar

X-ALD phenotypesstructure. Igarashiet al. (1976a) later showed that theseinclusions contained cholesterol esterified with saturatedClinical presentations

Table 1 summarizes the main phenotypes of X-ALD, whichvery long chain fatty acids (VLCFA). These findings stampedX-ALD as a lipid-storage disease and revolutionized the have been described in detail elsewhere (Kaback, 1972;

Schaumburget al., 1975; Griffin et al., 1977; H. W. Moserdirection of research.Singh et al. (1984a, b) in Baltimore demonstrated that et al., 1987, 1994; A. B. Moseret al., 1991; Sadeghi-Nejad

and Senior, 1990). A wide range of phenotypic variability isX-ALD patients had an impaired capacity to degradeVLCFA, and that this reaction normally takes place in the evident. The disease ranges from the rapidly progressive

childhood cerebral (CCER) form, which leads to totalperoxisome. This finding assigned X-ALD to the newlyrecognized category of peroxisomal disorders, along with the disability during the first decade, to the milder AMN, which

is compatible with survival to the eighth decade. These twoZellweger cerebrohepatorenal syndrome, which had beencharacterized by Goldfischeret al. (1973), also at the Albert forms of the disease differ fundamentally with respect to

age of onset (Fig. 1), length of survival (Fig. 2) andEinstein College of Medicine and in the same year asSchaumburg and Powers’ key observations about X-ALD. neuropathology. In CCER there is a diffuse demyelinative

process that involves the cerebral hemispheres, beginningAt that time, however, the relationship between the twodisorders was not recognized. Follow-up studies by Singh most commonly in the parieto-occipital region and is

Adrenoleukodystrophy 1487

Table 1 Phenotypes in X-linked adrenoleukodystrophy hemizygotes

Phenotype Description

Childhood cerebral Onset before 10 years of age, progressive behavioural and cognitive neurological deficits, inflammatory braindemyelination. Total disability often within 3 years.

Adolescent cerebral Like childhood cerebral, but onset at 10–21 years of age.

AMN Onset at 286 9 years, paraparesis progressive over decades, distal axonopathy, inflammation mild or absent,mainly spinal cord involvement, cerebral involvement later in 45% of cases.

Adult cerebral Rapid inflammatory cerebral progression resembling the childhood form, without preceding AMN, onset after21 years of age.

Addison’s disease only Primary adrenocortical insufficiency without neurological abnormalities.

Asymptomatic ALD gene abnormality without neurological or endocrine abnormalities.

Fig. 1 Age at onset of neurological symptoms of cerebral formsof X-ALD (broken line) and AMN (solid line). Note that the Fig. 2 Survival from time of first neurological symptomcerebral forms begin most commonly in childhood; adolescent (untreated males only). Note the rapid rate of progression ofand adult onset occurs only occasionally. The earliest onset of cerebral forms irrespective of age at onset. Filled circles5 AMNAMN was at the age of 12 years. (With permission, from Moser (n 5 116); filled triangles5 adult cerebral (n 5 3); pluset al., 1992.) signs5 adolescent cerebral (n 5 60); asterisks5 childhood

cerebral (n 5 257).

associated with a perivascular infiltration with lymphocytesand macrophages, resembling that seen in multiple sclerosis Van Geelet al., 1996). AMN may also present as a progres-

sive cerebellar disorder, resembling olivopontocerebellar(Siemerling and Creutzfeldt, 1923; Schaumburget al., 1975;Powers, 1985; Powerset al., 1992). MRI Studies show degeneration (Marsdenet al., 1982; Kurodaet al., 1983;

Ohnoet al., 1984).features that are often characteristic, with symmetricaldemyelination in the parieto-occipital region and accumula- In a series of 112 AMN patients we found that in 54%

the brain MRI was normal and demonstrable neurologicaltion of contrast material at the advancing margin (Fig. 3)(Kumar et al., 1987). There are other less character- involvement was confined to the spinal cord and peripheral

nerves (Kumaret al., 1995). These patients, to whom weistic patterns, however, such as early frontal involvement(MacDonaldet al., 1984; Castelloteet al., 1995) in ~15% of refer as cases of ‘pure AMN,’ have a better prognosis, and

their neuropsychological function is normal except for mildpatients, or presentation as an asymmetric mass lesion, whichhas been mistaken for a brain tumour (Younget al., 1982; deficits in psychomotor speed and visual memory (Edwin

et al., 1996). Forty-six percent of the AMN patients hadClose et al., 1993; Afifi et al., 1996). Magnetic resonancespectroscopy shows a diminution in theN-acetylaspartate various degrees of MRI abnormalities in brain, which were

associated with greater impairment of neuropsychologicalpeak and an increase in the choline peak (Kruseet al., 1994;Confort-Gounyet al., 1995; Rajanayagamet al., 1996). The function (Edwinet al., 1996) and a less favourable prognosis

(Fig. 4). We refer to these patients as AMN-cerebral. In somemagnetic resonance changes precede those demonstrableby MRI. In contrast to CCER, AMN is a distal axonopathy patients with AMN the MRI abnormality resembles that in

CCER, and clinical progression may be as rapid. Thus, somethat most severely involves the distal aspects of the longtracts in the spinal cord. The inflammatory reaction is patients with the slowly progressive AMN phenotype may

develop the rapidly progressive inflammatory cerebral diseasemild or absent (Schaumburget al., 1977; Powers, 1985;


Fig. 4 Rate of progression in various forms of adult X-ALD. Ascoring system which includes the MRI (Loeset al., 1994), anassessment of neuropsychological status (Shapiroet al., 1994) andthe Kurtzke expanded disability status score (Kurtze, 1989) wasused to estimate disability. With this system the most severedisability is scored as 35. The adult phenotypes are defined byKumar et al. (1995). ‘Pure AMN’ patients showed no sign ofcerebral involvement on the basis of clinical examination or MRI;AMN cerebral type 1 had brain MRI abnormalities confined tothe long tracts. The AMN cerebral type 2 patients had diffuselobar involvement on MRI, while the adult cerebral patients haddiffuse lobar involvement without preceding evidence of AMN.(With permission, from Kumaret al., 1995.) Filled squares5pure AMN; open squares5 AAAMN cerebral (type 1); filleddiamonds5 AMN cerebral (type 2); 0pen diamonds5 adultcerebral AMN.

Fig. 3 Brain MRI of a boy with childhood cerebral X-ALD; T1- Relative frequency of phenotypes and patternsweighted image with gadolinium contrast. Note large symmetricaldemyelination in parieto-occipital region and the accumulation of of distribution within kindredscontrast material at the anterior edge of the lesion. (With Estimates of the relative frequency of X-ALD phenotypespermission, from Moser, 1996.)

may be hampered by ascertainment bias, as mildly involvedpatients or those with unusual phenotypes are more likelynot to be diagnosed. We have used two approaches toreduce this bias. First, we have based our estimates onat a later age. The ‘adult cerebral’ patients are those who

develop rapidly progressive cerebral symptoms (associated the 123 pedigrees in which we have the most completeinformation, thus reducing the likelihood of excludingwith an inflammatory response) without prior evidence of

AMN. This distinction may not be absolute, because subtle undiagnosed X-ALD patients (Table 2). We have placedparticular emphasis on the relative frequency of the CCERsigns pointing to spinal cord or peripheral nerve involvement

may have been missed. Distinction between younger adoles- phenotype because, as discussed below, this value is importantfor the evaluation of therapeutic interventions. In this 123-cent cerebral and CCER, and older adolescent cerebral and

young AMN-cerebral patients may also be difficult. kindred sample, 37% of the patients had the CCER phenotype,and this percentage was not altered significantly when theApproximately 20% of women heterozygous for ALD

develop neurological disability which resembles AMN, but proband was excluded. Secondly, we analysed only thosesibships in which the genotype and phenotype of all affectedit is of later onset (mean age 37.86 14.6 years) and

somewhat milder than in affected males. Dr Sakkubai Naidu males had been ascertained (Table 3). In this somewhatsmaller sample, 39% of the patients had the CCER phenotype.has examined 165 heterozygous women who attended

meetings of the United Leukodystrophy Foundation mainly Exclusion of the proband reduced this figure to 33%. Ourresults are fairly comparable to those reported from thefor the sake of their affected sons. She noted that 53% of

these women showed some degree of neurological Netherlands (Van Geelet al., 1994) and France (Sereniet al.,1993), except that in the Dutch series AMN was the mostinvolvement which varied in severity from mild hyper-

reflexia and vibratory sense impairment with little or no common phenotype. Of note, nearly two-thirds of untreatedX-ALD patients escape the most severe phenotype, CCER.functional disability, to paraparesis requiring a wheelchair

in six patients. Signs of dementia, behavioural or visual The various phenotypes co-occur frequently in the samekindred or nuclear family (Table 4). Indeed, it is moredisturbances occur in 1–3% of heterozygous women, and

adrenal insufficiency in ~1% (H. W. Moseret al., 1991a). common for the severe and mild phenotypes to occur


Table 2 Percentage of ALD phenotypes in the 123 kindredsTable 4 Phenotype distribution among multiplex kindredsand multiplex nuclear familieswith two or more affected males

Phenotype Distribution (%) Phenotype Distribution (%)

All hemizygotes Hemizygote proband Multiplex kindredsCCER 54 (30.3)(n 5 637) excluded (n 5 530)CCER/AMN 90 (50.6)

Childhood cerebral 37 36 AMN 34 (19.1)Adolescent cerebral 7 5 Total 178AMN 32 32 Multiplex nuclear familiesAdult cerebral 3 3 CCER 66 (49.3)Addison only 13 15 CCER/AMN 35 (26.1)Asymptomatic 7 9 AMN 33 (24.6)

Total 134Our epidemiological survey of 826 kindreds currently includes2196 X-ALD hemizygotes, 1712 heterozygotes, 1290 persons ‘Nuclear families’ include sibships, and grandfather–grandsonwith diagnosis of X-ALD excluded by plasma VLCFA assay and relationship. ‘Kindreds’ include all relatives. ‘CCER’ indicates2128 persons without known neurological or adrenal dysfunction that the childhood cerebral form was the only phenotype in theattributable to X-ALD, but with X-ALD status not determined by kindred or nuclear family. ‘AMN’ indicates thatVLCFA assay. Since this last group includes undiagnosed mildly adrenomyeloneuropathy was the only phenotype. ‘CCER/AMN’involved X-ALD patients, the data may underestimate the indicates that the childhood cerebral form andproportion of mildly involved phenotypes. In an attempt to reduce adrenomyeloneuropathy were both present. The rarer phenotypesascertainment bias, we include only the 123 kindreds for whom in Tables 2 and 3 were present, but not included in this analysis.we have the most complete information.

Thedaet al., 1992). For the purpose of this discussion theTable 3 Phenotype distribution among ALD hemizygotes inabbreviation VLCFA refers to unbranched fatty acids with a253 sibships in which genotype and phenotype has been chain length of 24 carbons or greater. VLCFA are distributeddetermined in all male members widely in bacteria, plants, and normally also in mammalian

tissues, such as the brain, retina, skin and hair (Rezanka,Phenotype Distribution (%)1989; Poulos, 1995). In X-ALD tissues the excess is greatest

All affected males Hemizygote proband in nervous tissue white matter, the adrenal cortex and testis,(n 5 388) excluded (n 5 276) and in some lipid fractions, such as the cholesterol esters of

the adrenal gland and brain, the excess over control valuesChildhood cerebral 39 33may approach 1000-fold.Adolescent cerebral 6 4

AMN 26 26 In X-ALD patients, some degree of excess of saturatedAdult cerebral 2 2 VLCFA is present in all tissues and body fluids, and this hasAddison only 14 17 led to diagnostic assays with plasma (Moseret al., 1981;Asymptomatic 13 18

Moser and Moser, 1991), red blood cells (Tsujiet al., 1981b),cultured skin fibroblast, and also prenatal diagnosis (MoserThis analysis of phenotype is based exclusively on sibships in

which the genotype and phenotype of all males has been et al., 1982; Verhoevenet al., 1995). We have recently re-determined and it thus eliminates ascertainment bias introduced examined the sensitivity and specificity of the plasma VLCFAby persons whose X-ALD status is unknown. assay by analysing data obtained in.1000 male X-ALD

patients and 30 000 normal and non-peroxisome diseasewithin the same kindred than for a kindred to display onlycontrol subjects. We focused on three measurements, namely,a single phenotype. Consequently, because of phenotypicthe level of hexacosanoic acid (C26: 0), and its ratio toheterogeneity within families, comparison of clinical coursedocosanoic (C22: 0) and tetracosanoic (C24: 0) acids.in treated and untreated sibs is of limited value in assessingAlthough each was abnormal in X-ALD patients, somethe effectiveness of therapeutic interventions. Results ofoverlap with control subjects was observed. However, wesegregation analysis are discussed below. were able to develop a discrimination function that provides

virtually complete separation of X-ALD patients and controlsubjects (Fig. 5). With the aid of this function we have not

Biochemical abnormalities experienced the false-negative or equivocal results that havebeen reported from other laboratories (Wanderset al., 1993;Increased levels of saturated VLCFAs

The abnormal accumulation of saturated unbranched VLCFAs Kennedyet al., 1994). VLCFA are also increased in otherperoxisomal disorders (Verhoevenet al., 1995), including theis the principal and consistent biochemical abnormality in

X-ALD (Igarashi et al., 1976a; Menkes and Corbo, 1977; Zellweger syndrome, neonatal adrenoleukodystrophy andinfantile Refsum disease, but these disorders have aRamseyet al., 1979; Moseret al., 1980; Moser and Moser,

1991; Molzer et al., 1981; Tsuji et al., 1981b; Reinecke completely different clinical presentation and are almostnever confused with X-ALD. Approximately 85% of womenet al., 1985; Taketomiet al., 1987; Antoku et al., 1991;


is defective codes for a peroxisomal membrane protein, ALDprotein. Since transfection of X-ALD cells with ALD proteinrestores their capacity to oxidize VLCFA (Cartieret al.,1995), it must be concluded that the protein facilitates thisprocess in some way. Elucidation of the role of ALDprotein in VLCFA oxidation is under intense investigation.Possibilities include a role in the transport of VLCFA(Hettema et al., 1996) or their Co-A derivative into theperoxisome, or action as a platform for VLCS or itstransport.

GeneticsThe incidence of X-ALD is estimated to be between1 : 20 000 and 1 : 100 000 (Moseret al., 1995). During thelast 15 years we have identified 2238 hemizygotes in 740

Fig. 5 Discrimination function for males based on the three kindreds. Patients have been identified in many races andplasma measurements evaluated in our VLCFA assay for the

geographic locations, including Afro-Americans and nativediagnosis of X-ALD and peroxisomal disorders (Moser andAmericans, Hispanics, Jews, Chinese, Japanese and Maoris,Moser, 1991). Dotted lines, values in 1097 patients with

documented X-ALD; solid lines, values in 17 780 males who without apparent predilection for any one race. As alreadywere normal or who had a variety of nonperoxisomal disorders. noted, the gene has been mapped to X-q28 and has beenPostprandial samples are included, as VLCFA plasma levels do shown to be subject to X-inactivation (Migeonet al., 1981).not change greatly after eating. All ages are represented; VLCFA

The gene was isolated by positional cloning (Mosseret al.,levels in X-ALD patients do not vary with age (H.W. Moser,1993). It contains 10 exons and spans 20 kb of genomicunpublished observation). Although there is some overlap

between X-ALD and control when each of the three DNA. The protein product, ALD protein, contains 745 aminomeasurements are considered in isolation (data not shown), this isacids. It has been localized to the peroxisomal membranevirtually eliminated by application of the discriminant function (Mosseret al., 1994). ALD protein appears to be a member[function 5 5.028(C24/22) – 2.539(C26/22)1 3.317(C26: 0)].

of the ABC transporter superfamily (Higgins, 1992) a familyDiagnosis of those patients whose values fell within the smallof proteins that also includes the cystic fibrosis protein andregion of overlap is clarified by repeat analysis of a fasting

plasma sample or by study of cultured skin fibroblasts. (With the glycoproteins that impart multi-drug resistance. Thepermission, from Moseret al., 1981.) typical ABC transporter consists of two related halves that

together contain four domains. Two of these domains, onefrom each half, are highly hydrophobic and, in mostheterozygous for X-ALD have increased levels of VLCFA

in plasma and/or cultured skin fibroblasts (Moseret al., instances, consist of six membrane-spanning segments. Theseform a channel through which the substrate crosses the1983a), but false-negative tests do occur, so that the VLCFA

assay does not permit exclusion of heterozygote status. More membrane and they are believed to determine the specificityof the transporter. The other two domains are located on thedefinitive identification is achieved by mutational analysis

and immunocytochemical studies of the gene product (ALD cytoplasmic face of the membrane and share considerablesequence identity among ABC transporters. The ATP bindingprotein) (Watkinset al., 1995a; Feigenbaumet al., 1996).domain contains ~200 amino acids, and includes two short,highly conserved sequences, which are referred to as WalkerA and B. Figure 6 shows the overall structure of the gene,Cause of the increased VLCFA levels

The VLCFA excess is due to the impaired capacity to degrade as well as its relationship to the exons that code it and thelocation of the mutations that have been identified in X-ALDthese substances (Singhet al., 1984a), a reaction that normally

takes place in the peroxisome (Singhet al., 1984b). The patients. Many of the ABC transporter genes encode a half-transporter which then dimerizes either with an identicaldefect in VLCFA oxidation has been pinpointed to the first

step, i.e. the formation of the coenzyme-A derivative of molecule to form a homodimer or with another ABC half-transporter to form a heterodimer. Interestingly, peroxisomesVLCFA, a reaction that is catalysed by peroxisomal VLCS

(Lazoet al., 1988). This enzyme has been purified and cloned have been shown recently to contain four ABC half-transporters, namely ALD protein, ‘ALD-related protein’,only recently (Uchiyamaet al., 1996). VLCS has been

localized to the peroxisome, but there is dispute as to whether which has considerable homology to ALD protein but is notlocated on the X-chromosome (Lombar-Platetet al., 1996),it is located on the cytosolic or luminal surface of the

peroxisomal membrane (Lazoet al., 1990; Lageweget al., 70-kDa peroxisomal membrane protein (PMP70) (Kamijoet al., 1990; Gartneret al., 1992), and another protein related1991). It had been presumed that the gene defect in X-ALD

would be found to involve the formation of VLCS synthase, to the peroxisomal membrane protein (Shaniet al., 1995,1996). Whether ALD protein dimerizes with itself or withbut, as already mentioned and discussed below, the gene that


Fig. 6 Distribution of X-ALD mutations in 81 ALD probands. Data are based upon results in ourlaboratory and patients reported in the literature.Top: postulated structure of ALD protein (only onehalf of the typical ABC transporter dimer). The transmembrane domain spans the membrane six times.The ATP-binding domain is peripherally located at the cytoplasmic face of the membrane. The typicalABC transporter contains two such domains with a total of 12 transmembrane spanning regions and twoATP binding domains.Middle: genomic organization of ALD protein (Sardeet al., 1994). The intronsare not to scale.Bottom: location and relative frequencies of the mutations.

one of these other ABC transporters is not known. Further which was identical in 13 (17%) of unrelated families, andthus represents a ‘hot spot,’ most mutations were ‘private’,study of how these proteins relate to each other may provide

new insights about the function of ALD protein and the i.e. specific for a single kindred. Forty families (55%) hadmissense mutations, one of which occurred in three families,pathogenesis of ALD.

There is now convincing evidence that defects in ALD seven in two, and the remainder once. Frameshift mutationsoccurred in 23 families (30%), nonsense mutations occurredprotein are indeed the cause of X-ALD. Mutations in the

X-ALD gene have been demonstrated in all X-ALD patients in six (8%), splice defects in four (5%), and an amino aciddeletion was present in one family (1%). The exon 5 AGwho have been studied in sufficient detail, and these defects

have not been found in control samples. Furthermore, deletion has been associated with all phenotypes (Kempet al., 1994). In one kindred, a missense mutation wastransfection of X-ALD cells with the normal cDNA has been

shown to correct the defect in VLCFA oxidation (Cartier associated with five different phenotypes (Bergeret al.,1994). No correlation between the nature of the mutationet al., 1995). We have carried out mutational analyses in 35

unrelated X-ALD patients (Koket al., 1995). Approximately and phenotype has been detected so far.Immunocytochemical studies have shown that 70% of6% of patients have large deletions. Figure 6 shows the

nature, location and frequency of mutations in 81 X-ALD X-ALD patients lack ALD protein (Watkinset al., 1995b).No correlation was found between disease severity andpatients based upon our data and those reported in the

literature up to 1995. Except for an AG deletion in exon 5, the presence or absence of immunologically detectable


ALD protein. At the latest count (November, 1996), 105 brain are of dietary origin, at least in part. These investigatorsadministered 10 mg of deuterium-labelled C26: 0 ([3,3,5,5–separate mutations have been identified in 162 patients,

with an overall pattern comparable to that cited above2H]C26: 0) via a nasogastric tube to a terminally ill 9.5-year-old patient with CCER during the last 100 days of his(S. Kemp, personal communication).life. At post-mortem examination, cholesterol esters wereextracted from both mildly and severely involved whitematter, and the percentage of deuterium-labelled C26: 0 wasThe basis of the phenotypic variability: searchdetermined (Fig. 7). In the mildly involved area 96% of thefor a modifier geneC26: 0 was labelled. The pattern of label in the post-mortemThe severity of the biochemical defect (Boleset al., 1991),brain samples was similar to that which had been administeredor as noted above, the nature of the mutation, does notby mouth. This finding leads to the conclusion that nearlyaccount for the phenotypic variation in X-ALD. It has beenall of the abnormal fatty acid in that region had been derivedsuggested that a modifier gene might account for some offrom what the patient had been fed during the last 100 daysthe phenotypic variability (H. W. Moseret al., 1991a, b).of his life.Environmental factors may also play a role, as suggested by

Synthesis of fatty acids with chain length greater than 16two reports of phenotypic differences in two sets of identicalcarbons is carried out by a fatty acid elongation system,twins; in one, two Japanese men with the AMN-cerebralwhich is present in both mitochondria and microsomes. Thephenotype show moderate differences in respect to the agemicrosomal system appears to be more active and to haveof onset (32 versus 36 years) and severity of cerebralgreater physiological significance (Murad and Kishimoto,involvement and adrenal insufficiency (Sobueet al., 1994).1978). The reaction has been demonstrated in rat sciaticIn the other report, one 11-year-old boy developed typicalnerve (Cassagne and Darriet, 1978) and in cultured skinchildhood cerebral ALD at 10 years of age, while his twinfibroblasts (Tsujiet al., 1981a, 1985). Bourreet al. (1976)remains asymptomatic and has a normal MRI at 11 years ofconcluded that a single enzyme is responsible for theage (Korenkeet al., 1996). Further follow-up is requiredelongation of saturated fatty acids, such as behenic (C22: 0)to determine if this fundamental difference in expressionand its mono-unsaturated counterpart, erucic acid (C22: 1),will persist.a finding that provided the rationale for the dietary therapySince the presence or absence of the brain inflammatoryof X-ALD that is under current investigation. Studies inresponse is the main factor that differentiates the rapidlywhich deuterated water (2H2O) was administered to X-ALDprogressive cerebral forms of X-ALD from AMN and thepatients have demonstrated substantial C26: 0 synthesismilder variants, it is our working hypothesis that the(Moseret al., 1983b, 1995). Indeed, Tsujiet al. (1981a) andpostulated modifier gene acts by modulating the severity ofWilson et al. (1992) found that the microsomal elongatingthis response. Because of the postulated role of tumoursystem was more active in X-ALD than in control culturednecrosis factor (TNF)-α (Powers et al., 1992), which isskin fibroblasts, which may contribute to the VLCFAdiscussed below, we examined the possibility that variationsaccumulation in X-ALD. Dietary manipulation studies in X-in the inflammatory response might be related to variationsALD patients, which is discussed in the section on therapyin the TNF promoter, as has been shown for cerebral(and illustrated in Figs 12 and 13), indicate that endogenousinvolvement in malaria (McGuireet al., 1994), or to allelicsynthesis is quantitatively more important as a source offorms of the cytokine, as has been proposed for multipleVLCFA in X-ALD patients than is the diet.sclerosis (Hauser, 1995). There was no correlation between

either of these variables, however, and the severity of theinflammatory response in X-ALD (McGuinnesset al., 1995).

Effect of VLCFA on membrane structure andfunction

Pathogenesis The greater length of the aliphatic chain causes VLCFAs to beEvaluation of the pathogenesis of X-ALD is in a state of extremely insoluble and alters their physiological properties.flux. At this time, prime consideration is given to the role of Whereas albumin has six or more high- and low-affinityabnormally high levels of VLCFA, the principal biochemical binding sites for fatty acids with 12–18 carbon chain lengthabnormality that has been demonstrated so far. It is possible(Spector, 1975; Hamiltonet al., 1991), it has only a singlethat ALD protein has other functions unrelated to VLCFA low affinity binding site for hexacosanoic acid (C26: 0) (Hodegradation and that other, as yet unrecognized, pathogeneticet al., 1995). Desorption of C26: 0 from phospholipidmechanisms play a role. membranes is 10 000 times slower than that of fatty acids

with a 14–18 carbon chain length (Fig. 8) (Hoet al.,1995). Microcalorimetric studies have shown that inclusionof C26: 0 in a model membrane disrupts membrane structureSources of VLCFA

C26: 0 has two sources: diet and endogenous synthesis. (Fig. 9). The microviscosity of red-cell membranes isincreased in patients with X-ALD (Knazeket al., 1983). TheKishimoto et al. (1980) showed that the VLCFA in X-ALD


Fig. 7 Molecular ion regions of methyl hexacosanoate obtained by gas chromatograph-massspectrometry of various specimens: (A) synthetic methyl hexacosanoate; (B) synthetic methyl3,3,5,5–2H4 hexacosanoate; (C andD) fatty acid methyl esters from cholesterol esters from severelydegenerated white matter; (E) fatty acid methyl esters from cholesterol esters from mildly involvedwhite matter. In the mildly involved region 96% of the fatty acid was labelled, whereas in the severelyinvolved region this ranged from 0.4% (D) to 66% (C). (With permission, from Kishimotoet al., 1980.)

Fig. 8 First-order rate constant for transfer of saturated fatty acids from phospholipid bilayer (modelmembrane) to albumen as a function of chain length. The linear relationship on a semi-log plot of thesetwo variables indicates that the rate of desorption decreases exponentially with increased chain length.(With permission, from Hoet al., 1995.)

most direct evidence that abnormally high VLCFA levels Pathogenesis of adrenal dysfunctioncan alter membrane function is provided by the study ofAdrenal dysfunction in X-ALD is due to primaryWhitcomb et al. (1988), who assessed ACTH-stimulated adrenocortical insufficiency, and elevation of plasma ACTHcortisol release in cultured human adrenocortical cells. Thelevels is the initial manifestation (Blevinset al., 1994).addition of C26: 0 or C24: 0 to the culture medium in Although the extent of clinically evident adrenal insufficiencyconcentrations equivalent to those in X-ALD plasmais variable, as noted above, a substantial proportion of AMNincreased the microviscosity of adrenocortical cell membranespatients, and most heterozygotes, fail to show clinical orand decreased ACTH-stimulated cortisol secretion. Theybiochemical evidence of adrenal insufficiency. Microscopicconcluded that the excess VLCFA altered membrane structurestudy reveals some degree of adrenal involvement in nearlyand suppressed the availability of the ACTH receptor.all patients. Powerset al. (1987) demonstrated characteristicAnalogous effects may exist in neural membranes, but thisinclusions in a heterozygous woman who had a normal cortisol

response to ACTH stimulation.has not been demonstrated experimentally.


Fig. 9 Schematic diagram representing possible binding modes of C26: 0 molecules in a phospholipidbilayer that otherwise contains fatty acids with 16 or 18 carbon chain length. The C26: 0 moleculecould fit linearly and penetrate about halfway through the opposing phospholipid monolayer or couldbend in the middle of the bilayer. Calorimetric studies have shown that the C26: 0 molecules have adisruptive effect on membrane structure. (With permission, from Hoet al., 1995.)

Powers et al. (1980) have conducted a correlative with ‘pure’ AMN (Budkaet al., 1976; Schaumburget al.,morphological and cytochemical study that provides insight1977; Powers, 1985), which manifests most commonly ininto the pathogenesis of adrenal dysfunction. They concludedlate adolescence or adulthood; and (ii) the inflammatorythat the adrenal pathology is due to accumulation of abnormaldemyelinating lesion associated with the rapidly progressivelipids that contain VLCFA. The earliest change is the cerebral forms of the disease (Schaumburget al., 1975;appearance of birefringent, cytoplasmic striations withPowerset al., 1992), which, in the childhood form, oftenlamellae in cortical cells of the inner zonae fasciculata-leads to death before the age at which AMN manifests.reticularis. The lamellae represent the formation orAnalysis of the long-term course of the asymptomatic andprecipitation of lipid-protein aggregates or lipid bilayers Addison-only phenotypes suggests that all X-ALD patients(Fig. 10), which contain cholesterol esterified with VLCFA. who survive to adulthood will eventually develop theCells that contain these inclusions showed a reduction inmanifestations of AMN. The pathogenesis of the axonopathymitochondrial and microsomal enzymes. Inflammatory cellsis unknown. We speculate that the alterations in membranewere not present. As the disease advances, the adrenocorticalstructure and function associated with accumulation ofcells atrophy. VLCFA may play a pathogenetic role, but at this time there

Several factors can contribute to the accumulation of theseis no direct evidence for this. Studies in cultured Schwannabnormal cholesterol esters. (i) The impaired capacity tocells (Rutkowskiet al., 1995), or oligodendrocytes (Ishii andoxidize VLCFA. This leads to an increased proportion of Volpe, 1992), or other nerve cell culture systems may helpVLCFAs among the fatty acid precursors of cholesterolto clarify the pathogenesis of the axonopathy.esters. (ii) Cholesterol esterifying enzyme activity for C26:0 fatty acids is 16–38% that for oleic acid (C18: 1), far inexcess of the rate of hydrolysis of C26: 0-containingcholesterol esters, which is 1/1000 of those that contain C18:Pathogenesis of the inflammatory demyelinating1 (Ogino, 1980). This imbalance between the formation andlesiondegradation of C26: 0-containing esters would be expectedThe cerebral lesions in the rapidly progressive inflammatoryto lead to their increasing accumulation, and is the mostforms of X-ALD resemble those in multiple sclerosis. Inlikely cause for the lipid accumulation and the impairedboth conditions there is breakdown of myelin with relativeadrenal function. The VLCFA-containing cholesterol esters

sparing of axons, accumulation of cholesterol ester, and awould not be available as precursors for steroid hormone

perivascular inflammatory response with breakdown of thesynthesis. (iii) The previously cited studies by Whitcomb

blood–brain barrier. Griffinet al. (1985) have typed the cellset al. (1988) indicate that VLCFA excess in the plasmain the perivascular cuffs. They were able to identify 93% ofmembrane may impair the function of the ACTH receptor.the cells. Fifty-nine percent were T cells, 24% B cells, and11% monocytes/macrophages. Fifty-eight percent of the T

The nervous system displays two types of cells were T4, and 27% T8, while 15% could not beclassified. This pattern was similar to that found in the CNSpathologyduring a cellular immune response (Moench and Griffin,The nervous system pathology in X-ALD displays two

apparently disparate types: (i) the distal axonopathy associated 1984), and this suggested that one component of X-ALD is


Fig. 10 Adrenocortical cell containing both unilamellate and multilamellate inclusions that are both freein the cytoplasm and attached to various organelles (arrows). Electron micrograph taken from uranylacetate–lead citrate stained thin sections. Magnification:323 625. (With permission, from H. W. Moseret al., 1987.)

immunologically mediated, as is thought to be true for 1988) andin vivo (Selmaj et al., 1991a); it increases thepermeability of brain capillary endothelial cells (Deliet al.,multiple sclerosis.1995), and therapy with an antibody to TNF-α preventsthe development of experimental autoimmune encephalitis(Selmajet al., 1991b). Pro-inflammatory cytokines, includingRole of cytokinesTNF-α, therefore, are thought to be directly responsible forPowerset al. (1992) studied the patterns of expression oftissue damage in multiple sclerosis (Hauser, 1995). Thecytokine and effector molecules in post-mortem brain tissue offindings of Powerset al. (1992) provide support for thepatients with X-ALD and AMN. The most striking findinghypothesis that this is also true for the cerebral forms of X-was the expression of TNF-α in macrophages, and mostALD. Additional support is provided by the demonstrationprominently in astrocytes, at the active edge of the lesion.by McGuinnesset al. (1993) that the bioactivity of TNF-αExpression of TNF-α in astrocytes also occurs in multipleis increased in the serum of patients with the inflammatorysclerosis (Selmajet al., 1991a). TNF-α has been shown to

be toxic to oligodendrocytes bothin vitro (Selmaj and Raine, cerebral form of X-ALD and not in AMN (Fig. 11). Powers


.21 (Igarashiet al., 1976b). Such fatty acids are virtuallyabsent in normal brain gangliosides (Igarashiet al., 1976b).Gangliosides have been implicated in a variety ofneuroimmunological disorders (Pestronk, 1991). They havebeen shown to suppress Theiler’s murine encephalomyelitisdemyelinating disease (Inoueet al., 1996). Theimmunological properties of gangliosides vary with theirfatty acid composition (Kannagiet al., 1982). Gangliosidesthat contain 22–24 fatty acids are 6–10 times less effectiveimmunosuppressants than are those that contain fatty acidswith 16–20 carbons (Ladisch et al., 1994).Phosphatidylcholine is another possible trigger. Thedaet al.(1992) correlated the fatty acid composition of various lipidfractions in X-ALD brain with histopathological findings,reasoning that abnormalities in trigger molecules shouldprecede histopathological alterations. They found that inregions in which myelin was still intact, thephosphatidylcholine fraction showed the greatest VLCFAexcess: its VLCFA content was 16 times that of controlsubjects. Phosphatidylcholine is a major constituent of theplasma membrane, and neurological disorders with

Fig. 11 Serum levels of TNF-α bioactivity. Levels (U/ml) are antiphospholipid antibodies have been described (Levin andincreased in the advanced childhood cerebral (CCER) form (4) Welch, 1989). Bizzozeroet al. (1991) demonstrated ancompared with earlier stages of CCER (1–3), AMN and

abnormally high VLCFA content in myelin proteolipidasymptomatic (ASX) patients and control subjects (youngisolated from X-ALD brain, a finding that is of interest sincepatients,A, and adult normal,B). (With permission, from

McGuinnesset al., 1995.) antibodies to proteolipid protein have been implicated in thepathogenesis of multiple sclerosis (Warrenet al., 1994).

et al. (1992) have formulated the hypothesis that the primarybiochemical abnormality in X-ALD, i.e. the abnormalaccumulation of VLCFA, causes the liberation of lipids that

Comparison of the inflammatory response ininitiate a cytokine-mediated cascade.X-ALD with that in multiple sclerosisAlthough it is obvious that X-ALD and multiple sclerosisare fundamentally different disorders, the cerebral forms ofPossible triggers for the inflammatory response

In X-ALD, VLCFA excess is already present in foetal life X-ALD show an inflammatory demyelinating response thathas points of resemblance to multiple sclerosis. This suggests(Moser et al., 1982) and precedes the development of

brain pathology. We postulate that lipids containing an that the inflammatory cascades involved in both disordersmay have similar mechanisms, and since the primary causeabnormally high proportion of VLCFA can act as triggers to

initiate the cascade of inflammatory demyelination that of X-ALD is known, elucidation of the demyelinative processmay contribute to an understanding of multiple sclerosis. Theappears to be cytokine-mediated, perhaps by stimulating

TNF-α production in a manner analogous to the well-known points of resemblance between X-ALD and multiple sclerosishave already been cited; however, several differences haveeffect of lipopolysaccharide (Beutler and Cerami, 1988).

Whereas a mild to moderate excess of VLCFA is present in been noted in the past, and others have emerged recently. (i)In X-ALD, the lesions are large and confluent, rather thanall brain lipid species, the greatest excess occurs in the

ganglioside, phosphatidylcholine, proteolipid and cholesterol scattered throughout the nervous system. (ii) In multiplesclerosis, the inflammatory infiltrates are located at the activeester fractions. Even though in active demyelinating lesions

the cholesterol ester fraction contains the greatest excess of demyelinative edge, while in X-ALD they tend to be behindthe active edge (Schaumburget al., 1975; Powerset al.,VLCFA, this appears to be a consequence rather than a cause

of demyelination, because the fatty acid composition of this 1992). (iii) Oligoclonal bands in the cerebrospinal fluid arepresent in only a small proportion of X-ALD patients (H. W.fraction was normal in regions of X-ALD brain in which

myelin was still intact (Thedaet al., 1992). It is thus unlikely Moser, unpublished observation), but they are present inù90% of multiple sclerosis patients. (iv) The associationthat cholesterol esterified with VLCFA acts as a trigger for

the inflammatory response. However, each of the three other between multiple sclerosis and HLA-DR2 haplotypes thathas been documented repeatedly (Hillert and Orelup, 1993)components could play such a role, with gangliosides a

particularly plausible candidate. The gangliosides in X-ALD does not exist for the cerebral forms of X-ALD, whichshow a weak association with the HLA B-44 haplotypebrain contain 27.8–50% of fatty acids with a chain length


(McGuinnesset al., 1997). (v) McGuinnesset al., (1997)have recently compared inflammatory cytokine expressionin X-ALD and multiple sclerosis post-mortem brain tissue.The expression in multiple sclerosis was more intense thanin X-ALD, with Th2 cytokines predominant in multiplesclerosis lesions, and Th1 cytokines in X-ALD.

Taken together these results indicate that the mechanismof the inflammatory response in X-ALD differs from that inmultiple sclerosis.

TherapyAdrenal insufficiencyThe adrenal insufficiency responds readily to steroidreplacement therapy, but unfortunately may fail to berecognized. This is a serious error since adrenal insufficiencyhas been the cause of death in several patients who hadlittle or no neurological involvement. Restoration of adrenalfunction increases general strength and has improved schoolperformance in patients whose brain MRI was normal. Exceptfor one report, in a patient with AMN (Peckhamet al., 1982),steroid replacement therapy has not altered neurologicaldisability.

Fig. 12 Effect of diet and medications on plasma C26: 0 andC24: 0 fatty acids and on clinical course of ADL. Findings arerepresentative of those in six patients described by Brownet al.Neurological disability(1982). The diet reduced the intake of C26: 0 to,3 mg/day. TheThree therapeutic approaches are under current investigation:clofibrate dosage was 500 mg four times daily. There was no

diet, bone-marrow transplantation and immunosuppression.demonstrable effect on plasma levels of VLCFA or on clinicalAlthough none is as yet satisfactory, bone-marrowcourse. (With permission, from Brownet al., 1982.)transplantation shows the greatest promise. Evaluation ishampered by the variability of X-ALD, and still insufficient

progression (Fig. 12). The difference from the results inknowledge about its natural history.Refsum disease can be attributed to the demonstration thatphytanic acid is of dietary origin only (Steinberg, 1995),while, as already noted, VLCFA are derived both fromendogenous synthesis as well as the diet.Dietary therapy

The previously cited finding by Kishimotoet al. (1980) that The previously cited studies of Rizzoet al. (1986), thataddition of the mono-unsaturated oleic acid reduces the levelsthe VLCFAs in the brain of an X-ALD patient were of

dietary origin, at last in part, led to the design of a diet that of C26: 0 in cultured skin fibroblasts of X-ALD patients, ledto the trial of a regimen in which dietary restriction ofrestricts the intake of saturated VLCFA acids. Since standard

nutritional texts did not list C26: 0 content, we tested 135 VLCFA was combined with the administration of glyceryltrioleate (GTO) oil (A. B. Moseret al., 1987; Rizzoet al.,common foods and devised a diet that restricted the intake

of C26: 0 to,3 mg per day, compared with the 12–40 mg 1987). This regimen led to a 50% reduction of plasmaVLCFA levels in ~4 months (Fig. 13) and to a statisticallycontained in the customary American diet (Brownet al.,

1982; Van Duynet al., 1984). Achievement of this low intake significant improvement in one aspect of peripheral nervefunction, peroneal amplitude (H. W. Moseret al., 1991b),required restriction of fatty foods and the outer coverings of

vegetables and fruits. It had been our hope that, analogous although the statistical significance is not sustained whenBonferroni’s inequality is applied (Ingelfingeret al., 1987).to what had been found when phytanic acid intake was

restricted in patients with Refsum disease (Steinberg, 1995), As a result of the efforts of Mr and Mrs Odone, the diet wasaltered to a 4:1 mixture of GTO and glyceryl trierucatethe dietary restriction of the fatty acids that the patients were

unable to metabolize would lead to a reduction of plasma (GTE) oil, popularly referred to as Lorenzo’s oil, which willsubsequently be referred to as GTE. Erucic acid is an omegaVLCFA levels and clinical improvement. Five patients with

CCER and one man with AMN received the diet for periods 9 mono-unsaturated 22-carbon fatty acid, which, as notedpreviously, acts by competing with saturated fatty acids forranging from 3 months to 2 years. Unfortunately there was

no effect on either the plasma C26: 0 levels or clinical the microsomal fatty acid elongating enzyme system (Bourre


no higher than that in patients who had never received theoil (Table 5). It appears unlikely, therefore, that the GTE dietaffected the synthesis of C26: 0 and other saturated VLCFAin brain. Consistent with this conclusion is the finding thatin three of the four treated patients the levels of C26: 0 andsaturated VLCFA in various brain lipids were similar to thosein untreated X-ALD patients (Table 6). Of interest, however,is that in the one patient who had been treated with GTE forthe longest time (36 months) the C26: 0 levels in the totallipid, glycolipid and phospholipid fractions were normal(Table 6). Subject to the caution that this is only a single case,the data raise the possibility that prolonged normalization ofplasma C26: 0 levels can bring about a reduction of the brainC26: 0 levels. This result adds to the rationale for theprevention trial described below. The C26: 0 level in the

Fig. 13 Effect of GTE–GTO and GTO oil on plasma C26: 0 brain cholesterol fraction continued to be elevated, but, aslevels. The control group comprised 15 men with AMN who was noted previously, this fraction may reflect the lipidcontinued their customary diet. The GTO group consists of 16

composition of myelin lipids that had broken down at anAMN patients who were placed on the GTO diet described byearlier time. Furthermore, cholesterol esterified with VLCFAA. B. Moseret al. (1987). The GTE–GTO group includes

75 X-ALD patients with AMN or childhood cerebral X-ALD who is hydrolysed exceedingly slowly (Ogino and Suzuki, 1981).received the 4 : l mixture of GTO and GTE, as described in thetext. The baseline value for the GTE–GTO group is lower thanthat for the other groups because some of them had received GTObefore initiation of the GTE–GTO diet. The rapid drop in C26: 0 Possible preventive effect in asymptomaticlevel occurs irrespective of the baseline level or prior GTOtherapy (H. W. Moser, unpublished observation).Seetext for patientsdiscussion. Experience with disorders such as phenylketonuria and

hypothyroidism indicate that the timing of the correction ofthe metabolic defect is crucially important. Therapy initiatedet al., 1976). Erucic acid has a powerful effect on plasma

C26: 0 levels in X-ALD patients (Fig. 13). In most patients, in early life prevents mental retardation, but is not effectiveonce the neurological defect has become established. A trialthe level is normalized within 4 weeks. Since erucic acid

produces a cardiac lipidosis in rodents (Corner, 1983), there of preventive therapy is particularly relevant for X-ALD,since the disorder can be diagnosed at birth, and neurologicalhad been initial concern that it could cause heart damage.

However, cardiac side effects have not been documented involvement almost never begins before 4 years of age, andusually later (Fig. 1), thus providing a wide window ofclinically or by ECG or echocardiography in more than 100

patients (H. W. Moser, unpublished observation). Moderate opportunity for preventive therapy. We have identified 123neurologically asymptomatic X-ALD patients by testingreduction in platelet count is observed frequently, but has

not been associated with clinically significant bleeding, and plasma VLCFA levels in at-risk relatives of symptomaticpatients, as well as children with Addison’s disease. Patientscan be managed by reduction and monitoring of GTE intake

(Kickler et al., 1996). were assigned to the neurologically asymptomatic categoryif neither the patient, family, physician nor the teacherThe dramatic effect of GTE oil on the plasma levels of

VLCFA led to a series of therapeutic trials that have involved had reported neurological symptoms, and the neurologicalexamination is normal. All of these patients were invited tomore than 300 patients. For ethical reasons these were

conducted as open, nonrandomized trials. Although analysis participate in the dietary therapy protocol. The GTO-GTEmixture provides ~20% of total caloric intake, which isof data is not yet fully complete, the consensus is that

when the diet is administered to patients who are already accomplished with a daily dosage of 2–3 ml/kg. Other sourcesof fat provide 10–15% of total calories. Supplements ofneurologically involved, it has little or no effect on the

neurological progression (Rizzoet al., 1990; Rizzo, 1993; essential fatty acids, vitamins and minerals were provided,and platelet count, liver function and electrocardiogram wereUziel et al., 1990; Aubourget al., 1993; Kaplanet al., 1993;

Moser, 1993, 1995; Korenkeet al., 1995, 1996). A likely monitored. More than 80% of the patients who maintainedthe diet have had significant reduction or normalization ofexplanation for these disappointing results is provided by the

results of biochemical assays of the post-mortem tissues of plasma VLCFA levels. Details of the treatment protocol havebeen presented (A. B. Moseret al., 1987; H. W. Moserfive X-ALD patients who had received the oil for various

lengths of time (Pouloset al., 1994; Rasmussenet al., 1994). et al., 1991b).Evaluation of clinical efficacy presents a difficult challenge.Whereas substantial amounts of erucic acid were present in

adipose tissues and liver even months after the diet had been For ethical reasons, randomized placebo-controlled studydesign proved impossible. The hope engendered by thediscontinued, the erucic acid level in brain was minimal and


Table 5 Erucic acid (C22: 1) and nervonic acid (C24: 1) levels in ALD patients treated with GTE

Subjects Age at Time on Interval* Total lipid (% of total fatty acids)death therapy (months)

Adipose Liver Brain Brain(years) (months)triglyceride

C22: 1 C24: 1 C22: 1 C24: 1 C22: 1 C24: 1

Untreated (n 5 7) 11.3–51 0.026 0.13 0.26 0.018 0.096 0.061 0.03 0.226 0.11 6.036 1.78 0.226 0.07Treated

Patient 1 52.7 5 6 0.26 0.04 0.06 0.80 0.28 6.45 0.28Patient 2 7.3 5 9 1.29 0.19 0.04 0.77 0.29 4.44 0.49Patient 3 35.7 16 12 1.83 0.13 0.08 1.00 0.21 3.78 0.19Patient 4 10.2 35 3 3.00 0.10 0.46 0.52 0.11 2.43 0.13

*Interval between cessation of therapy and death. Note that the adipose tissue and liver of GTE-treated patients contained a 10- to 50-fold excess of erucic acid(C22: 1) or of its elongation product (C24: 1) even 12 months after the dietary therapy had been discontinued. In contrast, their content in brain was equal to that inuntreated patients. Pouloset al. (1994) reported comparable results in an X-ALD patient who had continued GTE therapy until the day he died.

Table 6 Brain C26: 0 levels as percentages of total fatty acids in ALD patients treated withLorenzo oil

Subjects Total lipid Cholesterol ester Phospholipids

Control subjects (n 5 19) 0.486 0.09 1.536 1.08 0.186 0.04Untreated ALD

ChildrenEarly (n 5 6) 0.706 0.40 12.056 1.82 0.296 0.13Late (n 5 10) 3.516 2.61 11.476 9.37 0.416 0.24

Adults (n 5 12) 1.096 0.50 5.056 1.36 0.356 0.09Treated #1 1.016 0.34 2.66 0.65Treated #2 2.696 0.55 7.15 1.226 0.33Treated #3 0.686 0.11 2.89 0.35Treated #4 0.206 0.06 6.82 0.14

Seetext for discussion.

striking biochemical effect, i.e. normalization of plasmaVLCFA levels, combined with the devastating course of theCCER phenotype prevented us from proposing a randomizedstudy design, and this position was sanctioned by ourInstitutional Review Board and by the National Institutesof Health who supported the study. The difficulty of evaluationis compounded by the complete lack of a historical controlgroup for the asymptomatic phenotype since the capacity toidentify asymptomatic patients by plasma VLCFA assaywas not achieved until 1981, only a few years before thedevelopment of dietary therapy.

Since the usual procedures for therapeutic evaluation areforeclosed, the appraisal will be based upon a comparison ofthe incidence of the CCER phenotype in the treated X-Fig. 14 Dietary therapy in X-ALD asymptomatic patients

(n 5 115). The three symbols indicate neurological status at lastALD patients with that in a representative sample of thefollow-up: open cicles5 normal (n 5 96); filled triangles5untreated X-ALD population. As discussed previously, andmild–moderate (n 5 12); asterisks5 severe (n 5 7). Note thatshown in Tables 2 and 3, we estimate that 33–39% of96 of the 115 patients have remained neurologically intact.See

untreated X-ALD patients will develop the CCER phenotype,text for further discussion.and that approximately two-thirds of untreated X-ALDpatients will escape it. Therefore, dietary therapy can bejudged to be an effective preventive only if significantly the CCER, and patients must be followed until they have

passed the age of greatest risk of developing the severemore than two-thirds of the treated patients escape the CCERphenotype. For the comparison to be meaningful, analysis of cerebral disease (12–14 years, as shown in Fig. 1).

Figure 14 shows the neurological status of the currentthe treated patients should focus on those asymptomaticpatients who began therapy before the usual age of onset of cohort. Neurological status has remained normal in 96 of


115 patients (83%). The CCER phenotype, leading to deathin four, occurred in seven (6%). Mild abnormalities, whichwould not be classified as CCER, occurred in 12%. Althoughthis overall result appears encouraging, it should beconsidered with caution. Five of the patients with severeoutcome had started the diet before the age of 5 years, andtwo had normalized their plasma levels completely. Thetherapy therefore is not an absolute preventive. At this time,only 10 of the patients meet the criteria for definitiveevaluation, namely initiation of therapy before the age of 6years and follow-up until the age of 12 years or later. Theseare the patients clustered in the upper left-hand corner of thefigure. Three of these 10 patients died or developed CCER.However, the number is far too small to draw conclusions.

We plan to continue this prevention trial for a further 3–5 years, and more patients are being enrolled. In addition tothe neurological appraisals, the evaluations include MRIstudies at yearly intervals, with quantitative scores assignedutilizing the system designed for this purpose by Loeset al.(1994) and detailed neuropsychological appraisals designedfor the study of leukodystrophy patients by Shapiro andcolleagues (Shapiro and Klein, 1994; Shapiroet al., 1995).We have also established a collaborative agreement with aEuropean study group coordinated by Drs Frank Roels andWolfgang Kohler, which will permit at least a doubling of

Fig. 15 Bone marrow transplant in a 13-year-old patient withthe study population. We have reached agreement on aX-ALD: effect on plasma VLCFA levels and vision. Dotted bandscommon study protocol and data will be pooled. Biostatisticalin first three panels indicate normal mean1 1 SD.analysis will utilize newly developed techniques of survival ‘WBC/mm3’ refers to peripheral blood total white blood cell

count. (With permission, from Moseret al., 1984.)analysis (Wang, 1991) and longitudinal analysis (Liang andZeger, 1986). We will also correlate clinical outcome withthe degree of normalization of plasma VLCFA levels. These encouraging biochemical effects (Fig. 15). Circulating white

blood cells acquired the capacity to degrade VLCFA, andcombined approaches should permit a definitive answer tothe important question of whether early dietary therapy can the plasma VLCFA level diminished 2 months after the

transplant, suggesting that the correction of the enzyme defectreduce the frequency and severity of subsequent neurologicaldisability. Even if dietary therapy proves to be of limited in bone marrow-derived cells was sufficient to alter the

overall metabolism of VLCFA. The rise in C26: 0 levelsvalue, the data will provide key baseline information for theevaluation of other modes of therapy, such as bone-marrow during and immediately following the transplant is probably

due to its mobilization from adipose tissues. Unfortunately,transplantation and gene therapy.the clinical results were discouraging. The patient lost hisvision on the seventeenth day after bone-marrow transplanta-tion, his neurological disability continued to advance, andBone marrow transplantation

The first bone-marrow transplantation for an X-ALD patient he died of an adenovirus infection 141 days after thetransplantation; thus, no additional transplants were per-was reported in 1984 (Moseret al., 1984). The rationale was

based upon the demonstration that normal bone marrow- formed during the next 4 years. Experience with 70 X-ALDpatients who have received bone-marrow transplantationderived cells can degrade VLCFA and that this capacity is

deficient in X-ALD patients (Singhet al., 1984a). Further- since then indicates that when transplants are performed inpatients who are already in the rapidly advancing stage ofmore, the intense perivascular lymphocyte and macrophage

infiltrates in X-ALD brain lesions make it likely that substan- the disease, the neurological disability continues to advancein the immediate post-transplant period, and the rate oftial numbers of bone marrow-derived cells would enter the

brain. At that time, the defective gene product had not yet progression may even accelerate. On the basis of this experi-ence, this first patient would now not be recommended forbeen identified, and it was hoped that, as had been shown to

be the case in lysosomal disorders (Walkleyet al., 1994), transplantation.The attitude toward bone-marrow transplantation wasthe gene product that is deficient in X-ALD might be

transferred from bone marrow-derived cells to nervous tissue revolutionized by the report of Aubourget al., (1990), whoperformed a transplant in a 7.5-year-old patient with mildcells. The patient was in the rapidly advancing stage of the

adolescent cerebral form of X-ALD. The study did show cognitive, neurological and MRI abnormalities; he demon-


strated not only stabilization of the course, but reversal of these patients cannot tolerate the temporary worsening thatis associated with the stress of the procedure. It is also notthe deficit 24 months later. Subsequent follow-up 8 years

after the transplant indicates that neurological examination recommended for asymptomatic patients with normal MRI,because these patients have a.50% chance of not developingand MRI are normal, and that neuropsychological function

is equal to that of his unaffected non-identical twin who had severe forms of the disease, and therefore should not besubjected to the risk of the procedure, considering that theserved as the donor (P. Aubourg, personal communication).

Partial reversal of neurological disability, over and above the overall mortality in the 70 patients who have been transplantedis 30%. The prime indication is in patients who show earlyvariation of the natural history of the disease, has been

observed in seven additional patients (W. Krivit and P. evidence of cerebral involvement on the basis of MRI andneuropsychological testing (Krivitet al., 1995). Detection ofAubourg, unpublished observation). The improvement

appears to occur after the first 6 months and may continue such abnormalities at an early stage, when therapy appearsto be most effective, requires monitoring of neurologicallyfor several years. Although additional follow-up and more

rigorous comparison with untreated patients matched for age asymptomatic patients at 6-month to 1-year intervals.Techniques for the prevention of graft versus host disease,and disease severity are required, these preliminary data

do suggest that bone-marrow transplantation can lead to and the design of immunosuppression regimens are underreview, and promise to lower the risk of the proceduresignificant neurological benefit. The mechanism by which

this benefit is achieved is unknown. The demonstration that (Krivitet al., 1995). In view of the rise of C26: 0 levels thatmay occur in connection with the transplant (Fig. 15), Drthe defective gene product in X-ALD is a peroxisomal

membrane protein (Mosseret al., 1993) appears to rule out Krivit recommends that plasma VLCFA levels be loweredwith the aid of the GTE regimen, before, during, and afterthe possibility that this product could be transferred from

bone marrow-derived cells to neuronal elements. It has been the transplant. If the apparently favourable effects of bone-marrow transplantation are confirmed, and the risk of thesuggested that the improvement is a result of the intense

immunosuppression that precedes the transplant procedure. procedure diminishes, the threshold for recommending it willbe lowered, and it may then be considered for asymptomaticAgainst this possibility is the observation that, in the patients

who have had favourable results, improvement has continued patients with abnormal MRI and for patients with AMN who,at this time, are generally not considered to be suitablelong after cessation of immunosuppression therapy. In addi-

tion, in one patient who had received intense immuno- candidates.suppression, but in whom engraftment did not occur,neurological disability continued to advance rapidly. In ourview, the most likely explanation for the favourable effect is

Immunosuppressionthat normally functioning bone marrow-derived cells thatImmunosuppression is administered in order to abolish orinclude microglia (Hickey and Kimura, 1988) metabolizereduce the brain inflammatory response that is associatedVLCFA and thus reduce their levels in brain, and interrupt thewith the rapidly progressive cerebral forms of the disease.cascade of demyelination. The observation that improvementThe aim is to convert these severe disorders into the some-appears to commence only 6 months after bone-marrowwhat milder AMN. These approaches have not been success-transplantation would be compatible with the slow turnoverful so far.of microglia (Lawsonet al., 1992), which may thus be

Immunosuppression with cytoxan has not been effectivereplaced by enzymatically competent cells at only a slow(Stumpfet al., 1981; Naiduet al., 1988). A double-blindedrate. In accordance with this hypothesis the key factor intherapeutic trial of thalidomide and ofβ-interferon therapyimprovement is the lowering of VLCFA levels in brain. Atis in progress in our clinic. Eighteen patients with cerebralpresent this must remain a hypothesis since, for ethicalinflammatory disease in whom the disease was consideredreasons, direct measurement in patients is not feasible. Thetoo advanced for bone marrow transplantation are participat-plasma VLCFA levels appear to be an unreliable indicatoring at this time, and a total enrollment of 60 is planned.of the level of VLCFA in brain. GTE therapy can normalizeThalidomide was selected because it reduces the activityplasma VLCFA levels (Fig. 13) without altering those inof TNF-α, which, as has been discussed, may have abrain (Table 6). Although bone-marrow transplantation haspathogenetic role in X-ALD (Powerset al., 1992), and it haslowered plasma VLCFA levels in some X-ALD patientsbeen of benefit in lepromatous leprosy (Sampaioet al.,(Aubourg et al., 1990; Moseret al., 1984), it has not done1993). Interferonβ-1b was selected because of the points ofso in others, and the post-transplant alteration in plasmaresemblance between the inflammatory forms of X-ALD andVLCFA levels does not correlate with the degree of clinicalmultiple sclerosis, and the demonstrated benefit ofβ interferonbenefit (Krivit et al., 1995).for certain forms of multiple sclerosis (Patyet al., 1993).Although bone-marrow transplantation appears to be theSince the code in this double-blinded study has not yet beenmost effective therapy for X-ALD, its application is in abroken, we cannot comment on the therapeutic effectiveness.state of flux and requires considerable care and judgement.There are anecdotal reports that immunoglobulins have beenIt is not recommended for patients with rapidly advancing

or severe cerebral involvement (Krivitet al., 1995) because of benefit (Okaet al., 1996).


Moser, unpublished observation), could lead to a trulyGene therapyeffective approach to this devastating disorder.X-ALD is a promising candidate for gene therapy, since the

condition can be diagnosed years before neurological damageoccurs. The gene has been isolated and has been shown tocorrect the defect in VLCFA metabolism in X-ALD cells Acknowledgements(Cartieret al., 1995). Further experience with bone-marrow I wish to thank Dr Kirby D. Smith for his support and criticaltransplantation and studies in animal models of the diseasereview of the manuscript. The work was supported in partwill be required to determine whether transfection of by grants HD 10981, RR00035, RR00052 and RR00722haematopoietic cells will suffice, or if additional approachesfrom the National Institutes of Health.need to be considered.

ReferencesAdams RD, Kubik CS. The morbid anatomy of the demyelinativeConcluding remarks diseases. Am J Med 1952; 12: 510–46.

Adrenoleukodystrophy has become the topic of intensiveAfifi AK, Menezes AH, Reed LA, Bell WE. Atypical presentation ofstudy in several laboratories and clinics in the United States,X-linked adrenoleukodystrophy with an unusual magnetic resonanceEurope and Japan. Analysis of the advances that have beenimaging pattern. J Child Neurol 1996; 11: 497–9.achieved, and of the problems that remain, points to several

issues that may apply to other neurogenetic disorders. TheAntoku Y, Koike F, Ohtsuka Y, Sakai T, Tsukamoto K, Nagara H,application of precise and non-invasive diagnostic techniques,et al. Adrenoleukodystrophy: a correlation between saturated very

long-chain fatty acids in mononuclear cells and phenotype. Annin this instance the plasma assay of VLCFA, has demonstratedNeurol 1991; 30: 101–3.that the disorder is more common, and that the range of

phenotypic expression is much wider, than had beenAubourg P, Blanche S, Jambaque I, Rocchiccioli F, Kalifa G, Naud-recognized in the past. Identification of the gene defect wasSaudreau C, et al. Reversal of early neurologic and neuroradiologicaccomplished by positional cloning, and the gene productmanifestations of X-linked adrenoleukodystrophy by bone marrowhas unexpected properties that do not readily account for thetransplantation. N Engl J Med 1990; 322: 1860–6.biochemical abnormalities or the pathogenesis of the disease.

Aubourg P, Adamsbaum C, Lavallard-Rousseau MC, RocchiccioliWhile the improved capacity for precise prenatal and postnatal

F, Cartier N, Jambaque I, et al. A two-year trial of oleic and erucicdiagnosis has facilitated genetic counselling, many newacids (‘Lorenzo’s oil’) as treatment for adrenomyeloneuropathy [seepatients continue to be identified in families that had notcomments]. N Engl J Med 1993; 329: 745–52. Comment in: Nbeen known to be at risk. Effective therapy still escapes us.Engl J Med 1993; 329: 801–2, Comment in: N Engl J Med 1994;Several urgent research needs remain. These include more330: 577, Comment in: N Engl J Med 1994; 330: 1904–5.detailed knowledge about the natural history of each of

Berger J, Molzer B, Fae I, Bernheimer H. X-linkedvaried phenotypes that may be associated with the sameadrenoleukodystrophy (ALD): a novel mutation of the ALD gene

primary gene defect. Recently developed transgenic mousein 6 members of a family presenting with 5 different phenotypes.models of X-ALD provide new opportunities to elucidate Biochem Biophys Res Commun 1994; 205: 1638–43.pathogenesis, and to design and evaluate new tharapies. One

Beutler B, Cerami A. The history, properties, and biological effectsof these models has been developed in Japan (Kobayashiof cachectin. [Review]. Biochemistry 1988; 27: 7575–82.et al., 1997), the other at the Kennedy Krieger Institute in

Baltimore (Luet al., in press). Both models are deficient in Bizzozero OA, Zuniga G, Lees MB. Fatty acid composition ofALD protein, also oxidation of VLCFA is defective and human myelin proteolipid protein in peroxisomal disorders. J

Neurochem 1991; 56: 872–8.VLCFA levels in brain and adrenal glands are increased. Themodel produced in Baltimore shows lamellar inclusions inBlaw ME. Melanodermic type leucodystrophy (adreno-the adrenal gland. The animals do not show neurologicalleukodystrophy). In: Vinken PJ, Bruyn GW, editors. Handbook ofchanges at 6 months (Baltimore) or at 12 months of ageclinical neurology, Vol. 10. Amsterdam: North Holland Publishing(Kobayashiet al., 1997). Strategies to enhance the phenotypeCompany, 1970: 128–33.include dietry loading with VLCFA, the additional knockout

Blaw ME, Osterberg K, Kozak P, Nelson E. Sudanophilicof other ABC transporters such as 70-kDa peroxisomalleukodystrophy and adrenal cortical atrophy. Arch Neurol 1964; 11:

membrane protein (PMP70) and ALD related protein, which626–31.

have been referred to previously, and cross-breeding withBlevins LS Jr, Shankroff J, Moser HW, Ladenson PW. Elevatedstrains that are highly susceptible to eperimental allergicplasma adrenocorticotropin concentration as evidence of limitedencephalitis. If and when effective therapy becomes available,adrenocortical reserve in patients with adrenomyeloneuropathy. Jthe development and implementation of mass screeningClin Endocrinol Metab 1994; 78: 261–5.techniques in the newborn, which should permit identification

of affected individuals before they develop symptoms sinceBoles DJ, Craft DA, Padgett DA, Loria RM, Rizzo WB. Clinicalvariation in X-linked adrenoleukodystrophy: fatty acid and lipidVLCFA in plasma are already increased at birth (H. W.


metabolism in cultured fibroblasts. Biochem Med Metab Biol 1991; membrane protein gene in Zellweger syndrome. Nat Genet 1992;1: 16–23.45: 74–91.

Goldfischer S, Moore CL, Johnson AB, Spiro AJ, Valsamis MP,Bourre JM, Daudu O, Baumann N. Nervonic acid biosynthesisWisniewski HK, et al. Peroxisomal and mitochondrial defects inby erucyl-CoA elongation in normal and quaking mouse brainthe cerebro-hepato-renal syndrome. Science 1973; 182: 62–4.microsomes. Elongation of other unsaturated fatty acyl-CoAs (mono

and poly-unsaturated). Biochim Biophys Acta 1976; 424: 1–7.Griffin JW, Goren E, Schaumburg H, Engel WK, Loriaux L.Adrenomyeloneuropathy: a probable variant of adrenoleuko-Brown FR 3d, Van Duyn MA, Moser AB, Schulman JD, Rizzodystrophy. Neurology 1977; 27: 1107–13.WB, Snyder RD, et al. Adrenoleukodystrophy: effects of dietary

restriction of very long chain fatty acids and of administration of Griffin DE, Moser HW, Mendoza Q, Moench T, O’Toole S, Mosercarnitine and clofibrate on clinical status and plasma fatty acids.AB. Identification of the inflammatory cells in the central nervousJohns Hopkins Med J 1982; 151: 164–72. system of patients with adrenoleukodystrophy. Ann Neurol 1985;

18: 660–4.Budka H, Sluga E, Heiss WD. Spastic paraplegia associated withAddison’s disease: adult variant of adreno-leukodystrophy. J NeurolHaberfeld W, Spieler F. Zur diffusen Hirn-Ru¨ckenmarksklerose im1976; 213: 237–50. Kindesalter. Dt Z Nervheilk 1910; 40: 436–63.

Cartier N, Lopez J, Moullier P, Rocchiccioli F, Rolland MO, Jorge Hamilton JA, Era S, Bhamidipati SP, Reed RG. Locations of theP, et al. Retroviral-mediated gene transfer corrects very-long-chainthree primary binding sites for long-chain fatty acids on bovinefatty acid metabolism in adrenoleukodystrophy fibroblasts. Procserum albumin. Proc Natl Acad Sci USA 1991; 88: 2051–1054.Natl Acad Sci USA 1995; 92: 1674–8.

Hauser SL. Tumor necrosis factor: immunogenetics and diseaseCassagne C, Darriet D, Bourre JM. Biosynthesis of very long chain[editorial; comment]. Ann Neurol 1995; 38: 702–4. Comment on:fatty acids by the sciatic nerve of the rabbit. FEBS Lett 1978; 90:Ann Neurol 1995; 38: 723–30.336–40.

Hettema EH, van Roermund CWT, Distel B, van den Berg M,Castellote A, Vera J, Vazquez E, Roig M, Belmonte JA, Rovira A. Vilela C, Rodrigues-Pousada C, et al. The ABC transporter proteinsMR in adrenoleukodystrophy: atypical presentation as bilateralPat1 and Pat2 are required for import of long-chain fatty acids intofrontal demyelination. AJNR Am J Neuroradiol 1995; 16 (4 Suppl): peroxisomes of Saccharomyces cerevisiae. EMBO J 1996; 15:814–5. 3813–22.

Close PJ, Sinnott SJ, Nolan KT. Adrenoleukodystrophy: a caseHickey WF, Kimura H. Perivascular microglial cells of the CNSreport demonstrating unilateral abnormalities. Pediatr Radiol 1993;are bone marrow-derived and present antigen in vivo. Science 1988;23: 400–1. 239: 290–2.

Confort-Gouny S, Vion-Dury J, Nicoli E, Cozzone PJ. Localized Higgins CF. ABC transporters: from microorganisms to man.proton magnetic resonance spectroscopy in X-linked[Review]. Annu Rev Cell Biol 1992; 8: 67–113.adrenoleukodystrophy. Paediatr Neuroradiol 1995; 37: 568–75.

Hillert J, Olerup O. Multiple sclerosis is associated with genes withinCorner AH. Cardiopathology associated with the feeding ofor close to the HLA-DR-DQ subregion on a normal DR15,DQ6,Dw2vegetable and marine oils. In: Kramer JKG, Sauer FD, Pigden WJ,haplotype. Neurology 1993; 43: 163–8.editors. High and low erucic acid rapeseed oils. Toronto: Academic

Ho JK, Moser H, Kishimoto Y, Hamilton JA. Interactions of a veryPress, 1983: 293–313.long chain fatty acid with model membranes and serum albumin:

Deli MA, Descamps M, Dehouck MP, Cecchelli R, Joo F, Abrahamimplications for the pathogenesis of adrenoleukodystrophy. J ClinCS, et al. Exposure to tumor necrosis factor-alpha to luminalInvest 1995; 96: 1455–63.membrane of bovine brain capillary endothelial cells cocultured

Hoefnagel D, Van Den Noort S, Ingbar SH. Diffuse cerebral sclerosiswith astrocytes induces a delayed increase of permeability andwith endocrine abnormalities in young males. Brain 1962; 85:cytoplasmic stress fiber formation of actin. J Neurosci Res 1995;553–68.41: 717–26.

Igarashi M, Schaumburg HH, Powers J, Kishmoto Y, KolodnyEdwin D, Speedie LJ, Kohler W, Naidu S, Kruse B, MoserE, Suzuki K. Fatty acid abnormality in adrenoleukodystrophy. JHW. Cognitive and brain magnetic resonance imaging findings inNeurochem 1976a; 26: 851–60.adrenomyeloneuropathy. Ann Neurol 1996; 40: 675–8.Igarashi M, Belchis D, Suzuki K. Brain gangliosides inFanconi A, Prader A, Isler W, Luthy F, Siebenmann R. Morbusadrenoleukodystrophy. J Neurochem 1976b; 27: 327–8.Addison mit Hirnsklerose im Kindesalter – Ein heredita¨res Syndrom

mit X-chromosomaler Vererbung? Helv Paediat Acta 1963; 18:Ingelfinger JA, Mosteller F, Thibodeau LA, Ware JH. Biostatistics480–501. in clinical medicine. 2nd ed. New York: MacMillan, 1987: 161.

Feigenbaum V, Lombard-Platet G, Guidoux S, Sarde CO, MandelInoue A, Koh CS, Yanagisawa N, Taketomi T, Ishihara Y.JL, Aubourg P. Mutational and protein analysis of patients andSuppression of Theiler’s murine encephalomyelitis virus inducedheterozygous women with X-linked adrenoleukodystrophy. Am Jdemyelinating disease by administration of gangliosides. JHum Genet 1996; 58: 1135–44. Neuroimmunol 1996; 64: 45–53.

Ishii S, Volpe JJ. Glycoprotein processing is required for completionGartner J, Moser H, Valle D. Mutations in the 70K peroxisomal


but not initiation of oligodendroglial differentiation from its Kruse B, Barker PD, van Zijl PCM, Duyn JH, Moonen CTW, MoserHW. Multislice proton magnetic resonance spectroscopic imagingbipotential progenitor cell. Dev Neurosci 1992; 14: 221–9.in X-linked adrenoleukodystrophy. Ann Neurol 1994; 36: 595–608.

Kaback MM. Thermal fractionation of serum hexosaminidases:applications to heterozygote-detection and diagnosis of Tay-Sach’sKumar AJ, Rosenbaum AE, Naidu S, Wener L, Citrin CM, Lin-disease. Methods Enzymol 1972; 28B: 862–7. denberg R, et al. Adrenoleukodystrophy: correlating MR imaging

with CT. Radiology 1987; 165: 497–504.Kamijo K, Taketani S, Yokota S, Osumi T, Hashimoto T. The 70-kDa peroxisomal membrane protein is a member of the Mdr (P-Kumar AJ, Kohler W, Kruse B, Naidu S, Bergin A, Edwin D, et al.glycoprotein)-related ATP-binding protein superfamily. J Biol Chem MR findings in adult-onset adrenoleukodystrophy. AJNR Am J1990; 265: 4534–40. Neuroradiol 1995; 16: 1227–37.

Kannagi R, Nudelman E, Hakomori S. Possible role of ceramide inKuroda S, Hirano A, Yuasa S. Adrenoleukodystrophy: cerebello-defining structure and function of membrane glycolipids. Proc Natlbrainstem dominant case. Acta Neuropathol (Berl) 1983; 60: 149–52.Acad Sci USA 1982; 79: 3470–4.

Kurtzke JF. The Disability Status Scale for multiple sclerosis:Kaplan PW, Kruse B, Bryan RN, Tusa RJ, Shankroff J, Heller J,apologia pro DSS sua [see comments]. Neurology 1989; 39: 291–et al. Changes in visual system abnormalities in adrenoleuko-302. Comment in: Neurology 1993; 43: 1447.dystrophy with Lorenzo’s oil [abstract]. Ann Neurol 1993; 34: 261.

Ladisch S, Li R, Olson E. Ceramide structure predicts tumorKemp S, Ligtenberg MJ, van Geel BM, Barth PG, Wolterman RA, ganglioside immunosuppressive activity. Proc Natl Acad Sci USASchoute F, et al., Identification of a two base pair deletion in five1994; 91: 1974–8.unrelated families with adrenoleukodystrophy: a possible hot spotfor mutations. Biochem Biophys Res Commun 1994; 202: 647–53.Lageweg W, Tager JM, Wanders RJ. Topography of very-long-

chain-fatty-acid-activating activity in peroxisomes from rat liver.Kennedy CR, Allen JT, Fensom AH, Steinberg SJ, Wilson R. X-

Biochem J 1991; 276: 53–6.linked adrenoleukodystrophy with non-diagnostic plasma very longchain fatty acids. J Neurol Neurosurg Psychiatry 1994; 57: 759–61.Lawson LJ, Perry VH, Gordon S. Turnover of resident microglia

in the normal adult mouse brain. Neuroscience 1992; 48: 405–15.Kickler TS, Zinkham WH, Moser A, Shankroff J, Borel J, MoserH. Effect of erucic acid on platelets in patients with Lazo O, Contreras M, Hashmi M, Stanley W, Irazu C, Singhadrenoleukodystrophy. Biochem Mol Med 1996; 57: 125–33. I. Peroxisomal lignoceroyl-CoA ligase deficiency in childhood

adrenoleukodystrophy and adrenomyeloneuropathy. Proc Natl AcadKishimoto Y, Moser HW, Kawamura N, Platt M, Pallante B,Sci USA 1988; 85: 7647–51.Fenselau C. Adrenoleukodystrophy: evidence that abnormal very

long chain fatty acids of brain cholesterol esters are of exogenousLazo O, Contreras M, Singh I. Topographical localization oforigin. Biochem Biophys Res Commun 1980; 96: 69–76. peroxisomal acyl-CoA ligases: differential localization of palmitoyl-

CoA and lignoceroyl-CoA ligases. Biochemistry 1990; 29: 3981–6.Knazek RA, Rizzo WB, Schulman JD, Dave JR. Membranemicroviscosity is increased in the erythrocytes of patients withLevine SR, Welch KMA. Antiphospholipid antibodies. [Review].adrenoleukodystrophy and adrenomyeloneuropathy. J Clin InvestAnn Neurol 1989; 26: 386–9.1983; 72: 245–8.

Liang KY, Zeger SL. Longitudinal data analysis using generalizedKobayashi T, Shinnoh N, Kondo A, Yamada T. Adreno-

linear model. Biometrika 1986; 73: 13–22.leukodystrophy protein deficient mice represent abnormality of verylong chain fatty acid metabolism. Biochem Biophys Res CommunLoes DJ, Hite S, Moser H, Stillman AE, Shapiro E, Lockman L,1997; 232: 631–6. et al. Adrenoleukodystrophy: a scoring method for brain MR

observation. AJNR Am J Neuroradiol 1994; 15: 1761–6.Kok F, Neumann S, Sarde CO, Zheng S, Wu KH, Wei HM, et al.Mutational analysis of patients with X-linked adrenoleukodystrophy.Lombard-Platet G, Savary S, Sarde CO, Mandel JL, Chimini G. AHum Mutat 1995; 6: 104–15. close relative of the adrenoleukodystrophy (ALD) gene codes for a

peroxisomal protein with a specific expression pattern. Proc NatlKorenke GC, Hunneman DH, Kohler J, Stockler S, LandmarkAcad Sci USA 1996; 93: 1265–9.K, Hanefeld F. Glyceroltrioleate/glyceroltrierucate therapy in 16

patients with X-chromosomal adrenoleukodystrophy/adreno-Lu J-F, Lawler AM, Watkins PA, Powers JM, Moser AB, Mosermyeloneuropathy: effect on clinical, biochemical and neurophysio-HW, Smith KD. A mouse model for X-linked adrenoleukodystrophy.logical parameters. Eur J Pediatr 1995; 154: 64–70. Proc Natl Acad Sci USA 1997. In press.

Korenke GC, Fuchs S, Krasemann E, Doerr HG, Wilichowski E,MacDonald JT, Stauffer AE, Heitoff K. Adrenoleukodystrophy:Hunneman DH, et al. Cerebral adrenoleukodystrophy (ALD) inearly frontal lobe involvement on computed tomography. J Computonly one of monozygotic twins with an identical ALD genotype. Assist Tomogr 1984; 8: 128–30.Ann Neurol 1996; 40: 254–7.

Marsden CD, Obeso JA, Lang AE. AdrenoleukomyeloneuropathyKrivit W, Lockman LA, Watkins PA, Hirsch J, Shapiro EG. presenting as spinocerebellar degeneration. Neurology 1982; 32:The future for treatment by bone marrow transplantation for1031–2.adrenoleukodystrophy, metachromatic leukodystrophy, globoid cellleukodystrophy and Hurler syndrome. [Review]. J Inherit Metab McGuinness MC, Wesselingh SL, Griffin DE, Powers JM, Moser

HW, Smith KD. Cytokines and inflammatory demyelinative lesionsDis 1995; 18: 398–412.


in adrenoleukodystrophy and multiple sclerosis [abstract]. J Neuro- Moser HW, Moser AE, Trojak JE, Supplee SW. Identification offemale carriers of adrenoleukodystrophy. J Pediatr 1983a; 103: 54–9.pathol Exp Neurol 1993; 52: 331.

McGuinness MC, Griffin DE, Raymond GV, Washington CA, Moser HW, Pallante SL, Moser AB, Rizzo WB, Schulman JD,Fenselau C. Adrenoleukodystrophy: Origin of very long chain fattyMoser HW, Smith KD. Tumor necrosis factor-α and X-linked

adrenoleukodystrophy. J Neuroimmunol 1995; 61: 161–9. acids and therapy [abstract]. Pediatr Res 1983b; 17: 293A.

Moser HW, Tutschka PJ, Brown FR 3d, Moser AE, Yeager AM,McGuinness MC, Powers JM, Bias WB, Schmeckpepper BJ, SegalAH, Gowda VC, et al. Human leukocyte antigens and cytokins Singh I, et al. Bone marrow transplant in adrenoleukodystrophy.

Neurology 1984; 34: 1410–7.expression in cerebral inflammatory demyelinative lesions of X-linked adrenoleukodystrophy and multiple sclerosis. J Neuroimmu-

Moser HW, Naidu S, Kumar AJ, Rosenbaum AE. The Adreno-nol 1997; 75: 174–82.

leukodystrophies. [Review]. Crit Rev Neurobiol 1987; 3: 29–88.McGuire W, Hill AVS, Allsopp CEM, Greenwood BM, Kwiatkowski

Moser HW, Moser AB, Naidu S, Bergin A. Clinical aspects ofD. Variation in the TNF-alpha promotor region associated with

adrenoleukodystrophy and adrenomyeloneuropathy. [Review]. Devsusceptibility to cerebral malaria. Nature 1994; 371: 508–10.

Neurosci 1991a; 13: 254–61.Menkes JH, Corbo LM. Adrenoleukodystrophy: accumulation of

Moser HW, Aubourg P, Cornblath D, Borel J, Wu YW, Bergin A,cholesterol esters with very long chain fatty acids. Neurology 1977;

et al. Therapy for X-linked adrenoleukodystrophy. In: Desnick27: 928–32.

RJ, editor. Treatment of genetic diseases. New York: ChurchillLivingstone, 1991b: 111–29.Migeon BR, Moser HW, Moser AB, Axelman J, Sillence D, Norum

RA. Adrenoleukodystrophy: evidence for X linkage, inactivation,Moser HW, Moser AB, Smith KD, Bergin A, Borel J, Shankroff J,

and selection favoring the mutant allele in heterozygous cells. Procet al. Adrenoleukodystrophy: phenotypic variability and implications

Natl Acad Sci USA 1981; 78: 5066–70.for therapy [published erratum appears in J Inherit Metab Dis 1992;15: 918]. [Review]. J Inherit Metab Dis 1992; 15: 645–64.Moench TR, Griffin DE. Immunocytochemical identification and

quantitation of the mononuclear cells in the cerebrospinal fluid,Moser HW, Koehler W, Borel J, Bergin A, Panoscha R, Davoli

meninges, and brain during acute viral meningoencephalitis. J ExpCT, et al. The many faces of X-linked adrenoleukodystrophy:

Med 1984; 159: 77–88.implications for pathogenesis and the evaluation of therapy. In:Wanders RJA, Schutgens RBH, editors. Peroxisomal disorders inMolzer B, Bernheimer H, Budka H, Pilz P, Toifl K. Accumulation

of very long chain fatty acids is common to 3 variants of adrenoleuko- relation to functions and biogenesis of peroxisomes. Amsterdam:Elsevier, 1994: 227–46.dystrophy (ALD). J Neurol Sci 1981; 51: 301–10.

Moser AB, Borel J, Odone A, Naidu S, Cornblath D, Sanders DB, Moser HW, Smith KD, Moser AB. X-linked adrenoleukodystrophy.In: Scriver CR, Beaudet AL, Sly WS, Valle D, editors. The metabolicet al. A new dietary therapy for adrenoleukodystrophy: Biochemical

and preliminary clinical results in 36 patients. Ann Neurol 1987; and molecular bases of inherited disease. 7th ed. New York:McGraw-Hill, 1995: 2325–49.21: 240–9.

Moser HW. Lorenzo oil therapy for adrenoleukodystrophy: a prema- Mosser J, Douar AM, Sarde CO, Kioschis P, Feil R, Moser H, et al.Putative X-linked adrenoleukodystrophy gene shares unexpectedturely amplified hope [editorial; comment]. Ann Neurol 1993; 34:

121–2. Comment on: Ann Neurol 1993; 34: 169–74. homology with ABC transporters [see comments]. Nature 1993;361: 726–30. Comment in: Nature 1993; 361: 682–3.

Moser HW. Komrower Lecture. Adrenoleukodystrophy: naturalhistory, treatment and outcome. [Review]. J Inherit Metab Dis 1995; Mosser J, Lutz Y, Stoeckel ME, Sarde CO, Kretz C, Douar AM,

et al. The gene responsible for adrenoleukodystrophy encodes a18: 435–47.peroxisomal membrane protein. Hum Mol Genet 1994; 3: 265–71.

Moser HW. Peroxisomal disorders. In: Berg BO, editor. Principlesof child neurology. New York: McGraw-Hill, 1996: 1234–48. Murad S, Kishimoto Y. Chain elongation of fatty acid in brain: a

comparison of mitochondrial and microsomal enzyme activities.Moser HW, Moser AB. Measurement of saturated very long chain

Arch Biochem Biophys 1978; 185: 300–6.fatty acids in plasma. In: Hommes FA, editor. Techniques indiagnostic human biochemical genetics. New York: Wiley-Liss, Naidu S, Bresnan MJ, Griffin D, O’Toole S, Moser HW. Childhood

adrenoleukodystrophy. Failure of intensive immunosuppression to1991: 177–91.arrest neurological progression. Arch Neurol 1988; 45: 846–8.

Moser HW, Moser AB, Kawamura N, Murphy J, Suzuki K,Schaumburg H, et al. Adrenoleukodystrophy: elevated C-26 fatty Ogino T. Biochemical study of adrenoleukodystrophy (ALD). Folia

Psychiatr Neurol Jpn 1980; 34: 117–25.acid in cultured skin fibroblasts. Ann Neurol 1980; 7: 542–9.

Moser HW, Moser AB, Frayer KK, Chen W, Schulman JD, O’Neill Ogino T, Suzuki K. Specificities of human and rat brain enzymesof cholesterol ester metabolism toward very long chain fatty acids:BP, et al. Adrenoleukodystrophy: increased plasma content of

saturated very long chain fatty acids. Neurology 1981; 31: 1241–9. implications for biochemical pathogenesis of adrenoleukodystrophy.J Neurochem 1981; 36: 776–9.

Moser HW, Moser AB, Powers JM, Nitowsky HM, Schaumburg HH,Norum RA, et al. The prenatal diagnosis of adrenoleukodystrophy. Ohno T, Tsuchida H, Fukuhara N, Yuasa T, Harayama H, Tsuji S,

Miyatake T. Adrenoleukodystrophy: a clinical variant presenting asDemonstration of increased hexacosanoic acid levels in culturedamniocytes and fetal adrenal gland. Pediatr Res 1982; 16: 172–5. olivopontocerebellar atrophy. J Neurol 1984; 231: 167–9.


Oka A, Saito M, Kubota M, Sakakihara Y, Yanigisawa M. Temporary The correlation between biochemical and histopathological findingsin adrenoleukodystrophy. J Neurol Sci 1985; 70: 21–38.improvement of neurological symptoms with gammaglobulin ther-

apy in a boy with adrenoleukodystrophy. Brain Dev 1996; 18:Rezanka T. Very-long-chain fatty acids from the animal and plant119–21.kingdoms. [Review]. Prog Lipid Res 1989; 28: 147–87.

Paty DW, Li DK, UBC MS/MRI Study Group, IFNB MultipleRizzo WB. Lorenzo’s oil–hope and disappointment [editorial; com-Sclerosis Study Group. Interferon beta-1b is effective in relapsing-ment] [see comments]. N Engl J Med 1993; 329: 801–2. Commentremitting multiple sclerosis. II. MRI analysis results of a multicenter,on: N Engl J Med 1993; 329: 745–52, Comment in: N Engl J Medrandomized, double-blind, placebo-controlled trial [see comments].1993; 330: 1904–5.Neurology 1993; 43: 662–7.

Rizzo WB, Watkins PA, Phillips MW, Cranin D, Campbell B, AviganPeckham RS, Marshall MC Jr, Rosman PM, Farag A, Kabadi U,J. Adrenoleukodystrophy: oleic acid lowers fibroblast saturated C22-Wallace EZ. A variant of adrenomyeloneuropathy with hypothal-26 fatty acids. Neurology 1986; 36: 357–61.amic-pituitary dysfunction and neurologic remission after glucocort-

icoid replacement therapy. Am J Med 1982; 72: 173–6. Rizzo WB, Phillips MW, Dammann AL, Leshner RT, Jennings SS,Avigan J, et al. Adrenoleukodystrophy: dietary oleic acid lowersPestronk A. Motor neuropathies, motor neuron disorders, andhexacosanoate levels. Ann Neurol 1987; 21: 232–9.antiglycolipid antibodies. [Review]. Muscle Nerve 1991; 14: 927–36.

Rizzo WB, Leshner RT, Odone A, Dammann AL, Craft DA, JensenPoser CM, van Bogaert L. Natural history and evolution of theME, et al. Dietary erucic acid therapy for X-linked adrenoleukodys-concept of Schilder’s diffuse sclerosis. Acta Psychiat Neurol Scandtrophy. Neurology 1989; 39: 1415–22.1956; 31: 285–331.

Rizzo WB, Leshner RT, Odone A, Craft DA, Jennings SS, JaitlyPoser CM, Goutieres F, Carpentier MA, Aicardi J. Schilder’sR, et al. X-linked adrenoleukodystrophy: biochemical and clinicalmyelinoclastic diffuse sclerosis [published erratum appears inefficacy of dietary erucic acid therapy. In: Uziel G, Wanders RJA,Pediatrics 1986; 78: 138]. Pediatrics 1986; 77: 107–12.Cappa M, editors. Adrenoleukodystrophy and other peroxisomal

Poulos A. Very long chain fatty acids in higher animals – a review.disorders. Amsterdam: Excerpta Medica, 1990: 149–62.[Review]. Lipids 1995; 30: 1–14.

Rutkowski JL, Kirk CJ, Lerner MA, Tennekoon GI. PurificationPoulos A, Gibson R, Sharp P, Beckman K, Grattan-Smith P. Veryand expansion of human Schwann cells in vitro [see comments].long chain fatty acids in X-linked adrenoleukodystrophy brain afterNat Med 1995; 1: 80–3. Comment in: Nat Med 1995; 1: 24–5.treatment with Lorenzo’s oil. Ann Neurol 1994; 36: 741–6.

Sadeghi-Nejad A, Senior B. Adrenomyeloneuropathy presenting asPowers JM. Adreno-leukodystrophy (adreno-testiculo-leukomyelo-Addison’s disease in childhood [see comments]. N Engl J Medneuropathic-complex). Clin Neuropathol 1985; 4: 181–99. 1990; 322: 13–6. Comment in: N Engl J Med 1990; 322: 54–5.

Powers JM, Schaumburg HH. The adrenal cortex in adreno-leukody-Sampaio EP, Kaplan G, Miranda A, Nery JAC, Miguel CP, Vianastrophy. Arch Pathol 1973; 96: 305–10. SM, et al. The influence of thalidomide on the clinical and

immunologic manifestation of erythema nodosum leprosum. J InfectPowers JM, Schaumburg HH, Johnson AB, Raine CS. A correlativeDis 1993; 168: 408–14.study of the adrenal cortex in adreno-leukodystrophy: evidence for

a fatal intoxication with very long chain saturated fatty acids. InvestSarde CO, Mosser J, Kioschis P, Kretz C, Vicaire S, Aubourg P,Cell Pathol 1980; 3: 353–76. et al. Genomic organization of the adrenoleukodystrophy gene.

Genomics 1994; 22: 13–20.Powers JM, Moser HW, Moser AB, Ma CK, Elias SB, Norum RA.Pathologic findings in adrenoleukodystrophy heterozygotes. ArchSchaumburg HH, Powers JM, Raine CS, Suzuki K, Richardson EPPathol Lab Med 1987; 111: 151–3. Jr. Adrenoleukodystrophy: a clinical and pathological study of 17

cases. Arch Neurol 1975; 32: 577–91.Powers JM, Liu Y, Moser AB, Moser HW. The inflammatorymyelinopathy of adreno-leukodystrophy: Cells, effector molecules,Schaumburg HH, Powers JM, Raine CS, Spencer PS, Griffin JW,and pathogenetic implications. J Neuropathol Exp Neurol 1992; 51:Prineas JW, et al. Adrenomyeloneuropathy: a probable variant of630–43. adrenoleukodystrophy. II. General pathologic, neuropathologic, and

biochemical aspects. Neurology 1977; 27: 1114–9.Rajanayagam V, Grad J, Krivit W, Loes DJ, Lockman L, Shapiro E,et al. Proton MR spectroscopy of childhood adrenoleukodystrophy.Schilder PF. Zur kenntnis der sogenannten diffusen Sklerose. Z gesAJNR Am J Neuroradiol 1996; 17: 1013–24. Neurol Pscyhiat 1912; 10: 1–60.

Ramsey RB, Banik NL, Davison AN. Adrenoleukodystrophy brain Schilder P. Zur Frage der Encephalitis Periaxialis Diffusa (Sogen-cholesteryl esters and other neutral lipids. J Neurol Sci 1979; 40:annte Diffuse Sklerose). Z ges Neurol Psychiat 1913; 15: 359–76.189–96.

Schilder P. Die Encephalitis periaxilis diffusa. Arch Psychiat Nerv-Rasmussen M, Moser AB, Borel J, Khangoora S, Moser HW. Brain,krankh 1924; 71: 327–56.liver and adipose tissue erucic and very long chain fatty acid levels

Selmaj KW, Raine CS. Tumor necrosis factor mediates myelin andin adrenoleukodystrophy patients treated with glyceryl trierucateoligodendrocyte damage in vitro. Ann Neurol 1988; 23: 339–46.and trioleate oils (Lorenzo’s oil). Neurochem Res 1994; 19: 1073–82.

Reinecke CJ, Knoll DP, Pretorius PJ, Steyn HS, Simpson RHW. Selmaj K, Raine CS, Cannella B, Brosnan CF. Identification of


lymphotoxin and tumor necrosis factor in multiple sclerosis lesions. hexacosanoic acid (C23: 0) by cultured skin fibroblasts from patientswith adrenoleukodystrophy (ALD) and adrenomyeloneuropathyJ Clin Invest 1991a; 87: 949–54.(AMN). J Biochem (Tokyo) 1981a; 90: 1233–6.

Selmaj K, Raine CS, Cross AH. Anti-tumor necrosis factor therapyabrogates autoimmune demyelination. Ann Neurol 1991b; 30: Tsuji S, Suzuki M, Ariga T, Sekine M, Kuriyama M, Miyatake T.

Abnormality of long-chain fatty acids in erythrocyte membrane694–700.sphingomyelin from patients with adrenoleukodystrophy. J Neuro-

Sereni C, Paturneau-Jouas M, Aubourg P, Baumann N, Feingoldchem 1981b; 36: 1046–9.

J. Adrenoleukodystrophy in France: an epidemiological study.Neuroepidemiology 1993; 12: 229–33. Tsuji S, Sano-Kawamura T, Ariga T, Miyatake T. Metabolism of

(17,18–3H2)hexacosanoic acid and (15,16–3H2)lignoceric acid inShani N, Watkins PA, Valle D. PXA1, a possible Saccharomyces

cultured skin fibroblasts from patients with adrenoleukodystrophycerevisiae ortholog of the human adrenoleukodystrophy gene. Proc

(ALD) and adrenomyeloneuropathy (AMN). J Neurol Sci 1985; 71:Natl Acad Sci USA 1995; 92: 6012–6.

359–67.Shani N, Steel G, Dean M, Valle D. Four half ABC transporters

Uchiyama A, Aoyama T, Kamijo K, Uchida Y, Kondo N, Orii T,may heterodimerize in the peroxisome membrane [abstract]. Am J

et al. Molecular cloning of cDNA encoding rat very long- chainHum Genet 1996; 59: A42.

Acyl-CoA synthetase. J Biol Chem 1996; 271: 30360–5.Shapiro EG, Klein KA. Dementia in childhood: issues in neuro-

Uziel G, Bertini E, Rimoldi M, Gambetti M. Italian multicentricpsychological assessment with application to the natural history and

dietary therapeutical trial in adrenoleukodystrophy. In: Uziel G,treatment of degenerative storage diseases. In: Tramontana MG,

Wanders RJA, Cappa ME, editors. Adrenoleukodystrophy and otherHooer SR, editors. Advances in child neuropsychology. New York:

peroxisomal disorders: clinical, biochemical, genetic and therapeuticSpringer Verlag, 1994: 119–71.

aspects. Amsterdam: Excerpta Medica, 1990: 163–80.Shapiro EG, Lockman LA, Balthazor M, Krivit W. Neuropsycho-

Van Duyn MA, Moser AB, Brown FR 3d, Sacktor N, Liu A, Moserlogical outcomes of several storage diseases with and without bone

HW. The design of a diet restricted in saturated very long-chainmarrow transplantation. [Review]. J Inherit Metab Dis 1995; 18:

fatty acids: therapeutic application in adrenoleukodystrophy. Am J413–29.

Clin Nutr 1984; 40: 277–84.Siemerling E, Creutzfeldt HG. Bronzekrankheit und sklerosierende

Van Geel BM, Assies J, Weverling GJ, Barth PG. Predominance ofEncephalomyelitis. Arch Psychiat Nervkrankh 1923; 68: 217–44.

the adrenomyeloneuropathy phenotype of X-linked adrenoleukodys-trophy in the Netherlands: a survey of 30 kindreds. NeurologySingh I, Moser AE, Moser HW, Kishimoto Y. Adrenoleukodystro-1994; 44: 2343–6.phy: impaired oxidation of very long chain fatty acids in white

blood cells, cultured skin fibroblasts, and amniocytes. Pediatr ResVan Geel BM, Koelman JH, Barth PG, Ongerboer de Visser BW.

1984a; 18: 286–90.Peripheral nerve abnormalities in adrenomyeloneuropathy: a clinicaland electrodiagnostic study. Neurology 1996; 46: 112–8.Singh I, Moser AE, Goldfischer S, Moser HW. Lignoceric acid is

oxidized in the peroxisome: implications for the Zellweger cerebro-Verhoeven NM, Kulik W, Van den Heuvel CMM, Jacobs C. Pre-

hepato-renal syndrome and adrenoleukodystrophy. Proc Natl Acadand post-natal diagnosis of peroxisomal disorders using stable-

Sci USA 1984b; 81: 4203–7.isotope dilution gas chromatography-mass spectrometry. J InheritMetab Dis 1995; 18 Suppl 1: S45–60.Sobue G, Ueno-Natsukari I, Okamoto H, Connell TA, Aizawa I,

Mizoguchi K, et al. Phenotypic heterogeneity of an adult form ofWalkley SU, Thrall MA, Dobrenis K, Huang M, March PA, Siegel

adrenoleukodystrophy in monozygotic twins. Ann Neurol 1994; 36:DA, et al. Bone marrow transplantation corrects the enzyme defect

912–5.in neurons of the central nervous system in a lysosomal storagedisease. Proc Natl Acad Sci USA 1994; 91: 2970–4.Spector AA. Fatty acid binding to plasma albumin. [Review]. J

Lipid Res 1975; 16: 165–79.Wanders RJA, van Roermund CWT, van Wijland MJA, SchutgensRBH, van den Bosch H, Schram AW, et al. Direct demonstrationSteinberg D. Refsum disease. In: Scriver CR, Beaudet AL, Sly WS,

Valle D, editors. The metabolic and molecular basis of inherited that the deficient oxidation of very long chain fatty acids in X-linked adrenoleukodystrophy is due to an impaired ability ofdisease. 7th ed. New York: McGraw-Hill, 1995: 2351–69.peroxisomes to activate very long chain fatty acids. Biochem

Stumpf DA, Hayward A, Haas R, Frost M, Schaumburg HH.Biophys Res Commun 1988; 153: 618–24.

Adrenoleukodystrophy. Failure of immunosuppression to preventneurological progression. Arch Neurol 1981; 38: 48–9. Wanders RJA, Schutgens RBH, Barth PG, Tager JM, van den Bosch

H. Postnatal diagnosis of peroxisomal disorders: a biochemicalTaketomi T, Hara A, Kitazawa N, Takada K, Nakamura H. An adult

approach. [Review]. Biochimie 1993; 75: 269–79.case of adrenoleukodystrophy with features of olivo-ponto-cerebellaratrophy: II. Lipid biochemical studies. Jpn J Exp Med 1987; 57: Wang MC. Nonparametric estimation from cross-sectional survival

data. J Am Stat Assoc 1991; 86: 130–43.59–70.

Theda C, Moser AB, Powers JM, Moser HW. Phospholipids in X- Warren KG, Catz I, Johnson E, Mielke B. Anti-myelin basic proteinand anti-proteolipid protein specific forms of multiple sclerosis.linked adrenoleukodystrophy white matter: fatty acid abnormalities

before the onset of demyelination. J Neurol Sci 1992; 110: 195–204. Ann Neurol 1994; 35: 280–9.

Watkins PA, Braiterman LT, Smith MA, Gould SJ, Moser AB, MoserTsuji S, Sano T, Ariga T, Miyatake T. Increased synthesis of


HW, et al. Adrenoleukodystrophy: immunologic characterization of rated fatty acids on fatty acid metabolism in cultured skin fibroblastsALDP [abstract]. Pediatr Res 1995a; 37 (4 Pt. 2): 155A. from adrenoleukodystrophy patients. J Neurol Sci 1992; 109:

207–14.Watkins PA, Gould SJ, Smith MA, Braiterman LT, Wei HM, Kok F,et al. Altered expression of ALDP in X-linked adrenoleukodystrophy.Young RSK, Ramer JC, Towfighi J, Weidner W, Lehman R,Am J Hum Genet 1995b; 57: 292–301. Moser HW. Adrenoleukodystrophy: unusual computed tomographic

appearance. Arch Neurol 1982; 39: 782–3.Whitcomb RW, Linehan WM, Knazek RA. Effects of long-chain,saturated fatty acids on membrane microviscosity and adrenocortico-tropin responsiveness of human adrenocortical cells in vitro. J ClinInvest 1988; 81: 185–8. Received December 12, 1996. Revised February 21, 1997.

Accepted February 27, 1997Wilson R, Tocher DR, Sargent JR. Effects of exogenous monounsatu-

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