Clin Gene/ 1994: 45: 217-218 Prirr/ed in Denmark . AN righrs reserved

C o p y r i ~ h t 0 Munkszaard 1994

Letter to the Editor

Achondroplasia with XXY karvotwe r' r ' l

CLINICAL GENETICS ISSN 0009-9163

Clin Genet 1994: 45: 217-218. 0 Munksgaard, 1994

To the Editor: There are instances with two (or even three)

Mendelian conditions in which both genes are in almost full expression. They are easily recognized simply by their phenotypes. Similarly, there are reports of a chromosomal abnormality occurring in a subject with a Mendelian disease. We observed such a case, which raised the question as to which of these entities would be manifested, as summar- ized below.

M.S., a male, born in 1969 in Hatay in Turkey, in the east Mediterranean, was referred to the Gen- etics Department when, because of his short stat- ure, his eligibility for military service was being considered. He is the last sib of a sibship of four, all the other sibs being normal and healthy, as are both parents. He is unmarried, and a relatively high-ranking businessman.

He presented a rhizomelic type of dwarfism, and all findings were compatible with the diagnosis of achondroplasia (Fig. 1). In brief: the head was large, the forehead being slightly protruding. There was midfacial hypoplasia and depressed nasal bridge. Both the upper and the lower lips were thick and the lower chin was slightly hypoplastic. The face and head seemed elongated, with low-set ears. Facial hair was absent except for some on the upper lip.

The slightly depressed chest was long with re- spect to the limbs. No gyneconiasty was present. The abdomen was slightly protruding and there was lumbar lordosis, dorso-lumbar scoliosis and slight kyphosis. Small cuboidal vertebral bodies with short pedicles, narrow lumbar interpedicular distances, small iliac wings and narrow sciatic notches were other features. The testes were hypo- plastic, whereas the penis appeared normal in size, the pubic hair being female in distribution and as scanty as the body hair. Semen analysis revealed oligozoospermy, but he did not allow testicular biopsy.

Both humeri and femurs were rhizomelic, with trident-like hands and short fingers. A flexion con-

Received 13 April, revised version received 7 December 1993, accepted for publication 20 January 1994

tracture of 20" of the right elbow, right ulnar devi- ation and internal ligamentous laxity of the knees were also noted. We performed chromosome analy- sis because of high levels of FSH and LH with a relatively low level of testosterone, and unexpect- edly found a 47,XXY constitution without evi- dence of mosaicism.

The diagnosis was achondroplasia associated with a 47,XXY chromosome complement, showing few symptoms attributable to Klinefelter syn-

Fig. 1. Propositus. Note typical features of ACH, obscuring signs and symptoms attributable to XXY karyotype.

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Letter to the Editor

drome. No other family members present either condition. We therefore considered the de n o w oc- currence of both point mutation and meiotic non- disjunction as etiological agents. His father died at 62 years of age; the mother is 58.

To the best of our knowledge, this is the second report of this combination. The interesting point here is that the achondroplasia gene dominates the clinical picture, as was the case in Kulakova & Ignat’ev (1 986). The physical signs and symptoms attributable to an XXY constitution are obscured, except for the hormonal profile. This karyotype does not suggest a common pathogenic mechanism in these cases (Pena et al. 1977, Genest et al. 1979). No simple explanation can be offered.

B. S. Say11 D. Giil

H. Cakirbay

References Genest P, Pouliot MA. Une translocation t(16;20) (41 l;q13)

pat de novo chez une enfante achondroplasique. L’Union Med Can 1979: 12: 1487-1489.

Kulakova TA, Ignat’ev IuT. Achondroplasia associated with Klinefelter’s syndrome. Klin Med Mosk 1986: 64: 126-128.

Pena J, Pombo M, Martinon JM, Ausede A, Noya M. Fusion of the short arms of two X chromosomes in a patient with phenotype of achondroplasia. J Genet Hum 1977: 25: 2 1 5-220.

Correspondence: Dr. Bekir Sitki Say11 Department of Genetics Ankara University Medical Faculty 06100 Sihhiye, Ankara Turkey

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