Brief Communication: Lactase Persistence and DairyIntake in Mapuche and Mestizo Populations FromSouthern Chile

Catalina I. Fern�andez and Sergio V. Flores*

Departamento de Antropolog�ıa, Universidad de Chile, Santiago de, Chile 7800284

KEY WORDS Mapuche population; dairy intake; lactose intolerance; LCT-13910C>Tpolymorphism

ABSTRACT Lactase persistence (LP) occurs at avery low frequency in indigenous populations from LatinAmerica, offering an opportunity to understand the rela-tionship between this genetic trait and patterns of dairyconsumption. Here, the frequency of LP is analyzedfrom Mapuche and -an adjacent- mestizo populationinhabiting the Araucan�ıa region. In addition to genotyp-ing for LP, participants were surveyed in relation to gen-eral perception and consumption habits of dairyproducts. Low LP frequency (10%) and very low dairy

intake was found among the Mapuche population ascompared with Mestizo populations inhabiting Chile.The survey reported that the main reasons for avoidanceof dairy were the gastrointestinal symptoms after dairyintake and cultural dietary habits. The interactionbetween low LP genotype frequency, low dairy intake,and sociocultural determinants is here discussed in thelight of their potential health outcomes. Am J PhysAnthropol 155:482–487, 2014. VC 2014 Wiley Periodicals, Inc.

Lactase persistence (LP) is a good model to under-stand the interaction among genetic and cultural traitsof human populations. Lactase nonpersistence (LNP) isthe ancestral condition in mammals and variation pat-terns of the enhancer region of LCT, the gene responsi-ble for the synthesis of lactase, have shown to be mainlythe outcome of natural selection (Bersaglieri et al., 2004;Tishkoff et al., 2007), as well as migration and admix-ture processes (Gerbault et al., 2009; Torniainen et al.,2009; Friedrich et al., 2012a) that have affected popula-tions over time. LP is an autosomal dominant trait (Sahiet al., 1973), being LNP the most common phenotypeamong human populations worldwide (Ingram et al.,2009a). LP/LNP phenotypes are associated with at leastfive mutations: 213907C>G (Tishkoff et al., 2007),213910C>T, generally linked to 222018G>A (Enattahet al., 2002; Lewinsky et al., 2005), 213915T>G (Ingramet al., 2007; Tishkoff et al., 2007), 214010G>C (Jensenet al., 2011) and 214009T>G (Jones et al., 2013).

Dairy consumption in LNP individuals results in lac-tose malabsorption, whose physiological effects includethe inability to digest lactose that can lead to anincrease of bacterial fermentation in the small intestine(Arola and Tamm, 1994). As a consequence, the LNPstate can generate lactose intolerance (OMIM #223100),with the development of gastrointestinal symptoms(Vesa et al., 2000; Lomer et al., 2008).

In Latin America, according to the genetic ancestryand degree of admixture, there is a high variability inLP frequencies. The Amerindian groups of each countryexhibit the lowest proportion of LP. The frequency ofthis condition in populations that are virtually nonad-mixed, such as the Xavante of Brazil and the Guahibo ofColombia, is close to zero (Osier et al., 2002; Friedrichet al., 2012b), while in Mestizo populations of the samecountries the frequencies of LP are 43.4% and 20%,respectively (Mattar et al., 2009; Mendoza et al., 2012).In Chile, a recent study found that LP prevalence, esti-

mated by 213910C>T locus frequencies in the MCM6gene region (the European variant), was near 10% in aChilean Amerindian sample, while for Mestizo popula-tion of the capital of Chile (Santiago) it was �40%(Morales et al., 2011). This pattern is consistent with theEuropean origin of the colonists, the low African compo-nent in Chile (Arcos-Burgos et al., 2004) and lack ofdeep-seated milking practices.

One of the most accepted hypotheses regarding theevolution of LP in humans suggests that the LP state isassociated with pastoralism, as has been observed innorthern Europe, Asia, and Africa (Enattah et al., 2002;Tishkoff et al., 2007; Ingram et al., 2009b). In the Ameri-cas there is no evidence of an emergent mutation associ-ated with LP, and cattle were first introduced onlyrecently with the arrival of Columbus (Primo, 1992).Furthermore, there is no evidence of domestication ofother milking animals prior to European colonization(Stahl, 2008). In Chile, the milking practice was intro-duced recently, particularly in the Araucan�ıa region insouthern Chile, where this activity grew in the begin-ning of the 20th century in conjunction with the arrivalof European settlers (Pinto, 2011).

The Mapuche are the largest Chilean native popula-tion, and one of the largest of the Americas. Despite

Additional Supporting Information may be found in the onlineversion of this article.

*Correspondence to: Sergio Flores Carrasco, Ignacio CarreraPinto 1045, Departamento de Antropolog�ıa.E-mail: sfloresc@uchile.cl

Received 10 April 2014; accepted 5 August 2014

DOI: 10.1002/ajpa.22594Published online 14 August 2014 in Wiley Online Library

(wileyonlinelibrary.com).

� 2014 WILEY PERIODICALS, INC.

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 155:482–487 (2014)

Spanish colonization, a long and characteristic culturaltradition, language and territory had distinguished thisAmerindian group over centuries (Bengoa, 2007). How-ever, nowadays a growing acculturation process isnoticeable as a consequence of Nation State formationmechanisms and globalization influences (CONADI,2003). The acculturation process has had various effects,including a change in diet toward increased consumptionof non-Mapuche food instead of traditional food (Carra-sco et al., 2004; Peredo and Barrera, 2005; Aranedaet al., 2010; Schnettler et al., 2010).

Nearly 31% of the 913,065 inhabitants of the Arau-can�ıa region are of Mapuche ethnicity; being the regionwith the greatest proportion of Amerindian populationin Chile (INE, 2014). However, currently most of themhave been relegated to native reservations (Bengoa,2000), which has promoted the isolation and diminishedthe chance of admixture afterwards.

Since there is a lack of data on allele frequencies of theLNP polymorphisms in the region and their relationshipwith dietary and sociocultural variables, the aim of thisresearch is to estimate the gene frequencies of the LCT-13910C>T polymorphism in the geographic region withthe highest Amerindian contribution and analyze its rela-tionship to dairy consumption, symptomology, and socio-cultural variables associated with dietary patterns.

SUBJECTS AND METHODS

Subjects

The sample included individuals over 18 years old inhab-iting the rural places of the Araucan�ıa region. Samplingwas performed in local markets, public squares, commu-nity centers, and volunteer residences at different rurallocations in Temuco, Freire, and Pitrufqu�en localities.

A total of 144 individuals were investigated. The samplewas divided into two subsets (Mestizo and Mapuche)according to the sampling criterion. Individuals were clas-sified as Mapuche if they currently reside on a Mapuchereservation, both parents have Mapuche surnames and allthree were born in a Mapuche reservation. Individualswere classified as Mestizos of the Araucan�ıa region whenthey reported that they inhabit in the Araucan�ıa regionand have ancestors born in the region for at least one gen-eration. The Mestizo subset comprised 115 individualswho were asked to give a saliva sample of 2 ml and toanswer a short questionnaire about the place of birth oftheir parents and grandparents. A more in-depth studywas performed for the Mapuche subset in order to identifydistinctive features of the dairy food habits in this popula-tion and to complement the data of these variables previ-ously studied in the mixed population of this area. Thisincluded a survey of three kinds of information (question-naire, interviews, and DNA samples) under a nonprobabil-ity sampling. As a result, the Mapuche subset wascomposed of 29 individuals from Mapuche native reserva-tions of the Freire and Pitrufqu�en localities. All of the indi-viduals accepted voluntarily their collaboration with thisstudy by signing a written informed consent form previ-ously approved by the Humanity and Social SciencesResearch Ethics Committee, University of Chile.

Methods and analyses

DNA extraction was performed following the protocolproposed by Quinque et al. (2006). Samples were ampli-fied by polymerase chain reaction (PCR) for two DNA

fragments in the MCM6 region, each containing a singlenucleotide polymorphism (SNP) associated with the LP/LNP phenotype. The SNPs chosen were LCT-13910 C>Tand 222018G>A, both associated with the LP/LNP statein Europeans (Enattah et al., 2002) and in the mixedChilean population, as was demonstrated by Moraleset al. (2011) and N. Montalva (pers comm. 19 May, 2014)using the hydrogen breath test along with genotyping.

The regions surrounding both SNPs were amplified byprimers previously proposed by Bulh~oes et al. (2007). A210 bp fragment including the 213910C>T SNP wasgenerated by primers forward 50-AAGACGTAAGTTACCATTTAATAC-30 and reverse 50-CGTTAATACCCACTGACCTATCCT-30, while a 220 bp fragment including the222018G>A was generated by primers forward 50-TAAGAACATTTTACACTCTTC-30 and reverse 50-AGAAAATGGGTTTTCGCCATG-30.

SNP genotyping was carried out through PCR-restriction fragment length polymorphism (RFLP). Theamplified product of the 213910C>T was digested usingBsmFI (Fermentas) enzyme, while amplified product ofthe 222018G>A was digested by HhaI (Fermentas)enzyme. The digested PCR products were separated byelectrophoresis on agar gels. Genotyping corroborationwas performed through sequencing (Macrogen, Korea) intwo samples of each genotype using the forward primer.Concordance between the PCR-RFLP samples and thesequencing was confirmed in all cases.

Additionally, the Mapuche subset individualsanswered a questionnaire (Supporting InformationMaterial 1) applied by personal interview about cultural,dietary and other variables commonly associated withthe LNP state: (a) symptomology and digestive diseases,(b) value attributed to dairy consumption, (c) obstaclesfaced for dairy consumption, and (d) dairy intake (seeSupporting Information 2 for methodological criteriaused in each item). The dairy intake was measuredusing a dietary food frequency questionnaire (FFQ), con-sidering consumption in the previous 12 months. Theaim of this instrument was also to estimate the propor-tion of individuals reaching the Chilean standard nutri-tional recommendations, which suggest 3 servings ofdairy products per day (Olivares and Zacar�ıas, 2013).This was done in order to compare with similar datapreviously obtained for the mixed population of southernChile by the Ministry of Health (MINSAL, 2011).

Differences in allele frequencies between populationsubsets were tested using Pearson’s chi square test (R CoreTeam, 2012). The LCT 213910C>T locus was tested forgenotypic deviation from Hardy-Weinberg Equilibrium(HWE) using an exact test in the Arlequin software, ver-sion 3.0 (Excoffier et al., 2005). Genetic differentiationamong subsets and a sample from an urban area of San-tiago, Chile (Morales et al., 2011) was estimated by the FST

fixation index (Wright, 1978) using Arlequin.

RESULTS

A total of 144 samples (115 Mestizo of the Araucan�ıaregion and 29 from the Mapuche population) were suc-cessfully amplified and genotyped for LCT-13910C>Tand LCT-22018G>A loci. There was complete genotypiccorrelation between the LCT-13910C>T and 222018G>A SNPs in all individuals, thus hereafter only the LCT-13910C>T SNP will be considered.

The allele and genotype frequencies for the LCT-13910C>T locus were obtained directly by gene counting

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and are shown in Table 1. The Mapuche, Mestizos andcombined datasets did not deviate from the expectationsof HWE for the LCT-13910C>T locus (P 5 0.769, P 50.135, and P 5 0.089, respectively). Assuming Hardy-Weinberg equilibrium, we predicted the phenotypic fre-quency of LP in each subset population. Thus, LP preva-lence in Mapuche people was 10%, while in the mixedpopulation of Araucan�ıa region it was 30%. Additionally,the difference in the number of C and T alleles in eachpopulation was statistically significant (P(v2) 5 0.017)which validates the initial separation of the two subsets.

Genetic differentiation between the samples of theAraucan�ıa region and a representative admixed popula-tion of Santiago, the capital of Chile (Morales et al.,2011), was estimated by the FST index (Table 2). HigherFST values in pairwise population comparisons wereshown between the Mapuche population and theadmixed population of Santiago (P < 0.001).

Each dairy type show a similar pattern of dairy con-sumption, where most of the individuals were classifiedat the low frequency categories (Table 3). Dairy intakewas about 28 servings per month on average, whichindicates nearly one daily serving. Regarding the propor-tion of individuals reaching the recommended number ofservings per day (3/day), no individual met the dietaryguidelines for dairy products, while this proportion inmixed population of this area (south-central Chile) isabout 21.3% (MINSAL, 2011). As to milk intake, almost50% of this sample never consumes this food.

In spite of remarkably low dairy intake, most of theindividuals (90%) have a very positive opinion about thenutritional value and importance of dairy products inthe regular diet. Among the reasons given for not includ-

ing dairy products in the diet, the most common chosenalternatives were gastrointestinal symptoms (55%) andcultural habits (52%). Only 49% of the LNP individualsreported that they exhibit symptoms after dairy inges-tion (see Supporting Information 3 for a summary of thequestionnaire responses). Diagnosed gastrointestinalpathologies or medical conditions such as gastroenteritisor irritable bowel syndrome seemed to be better associ-ated with experiencing gastrointestinal symptoms afterdairy intake (P(v2) 5 0.052) than the expected LNPphenotype.

Statistical associations between LP/LNP and othervariables (i.e., dairy consumption patterns, gastrointesti-nal symptoms, value attributed to dairy product, etc.)were not performed due to the low number of individualshaving an LP associated genotype among Mapuche pop-ulation (n 5 3).

DISCUSSION

This is the first study about the relationship of lactasepersistence polymorphisms and dietary and socioculturalvariables in a native population of the Americas. Addi-tionally, it is the first research that reports the LCT-13910C>T and LCT-22018 G>A polymorphism frequen-cies in admixed and Amerindian (Mapuche) populationsof the Araucan�ıa region of Chile.

The frequency of LNP among the Mapuche reportedhere is closer to the prevalence of this trait in otherindigenous groups of South America (see Mattar et al.,2009; Mendoza et al., 2012). As compared to previousstudies in Chilean populations (Lacassie et al., 1978;Morales et al., 2011), the Mapuche population exhibitsthe highest frequency of LNP. Furthermore, our resultsare coincident with those obtained by Morales et al.(2011) in a previous study on urban Mapuche patients,who found an LNP frequency of 88.3%. The rural andadmixed population of the Araucan�ıa region showedlower frequencies of LNP, intermediate to the Mapucheand the admixed population of Santiago (Morales et al.,2011). This pattern of differentiation between admixedversus indigenous populations is in agreement with find-ings reported in other Latin American countries (seeMattar et al., 2009; Mendoza et al., 2012; Friedrichet al., 2012a).

Similarly, the greatest genetic differentiation (esti-mated by FST) was found between the admixed popula-tion of Santiago and Mapuche. This differentiation couldbe the result of geographic distance and also, due to dif-ferential ancestry contribution, considering that San-tiago city attracted immigrants since the late nineteencentury (Romero, 1984). On the other hand, theMapuche way of life establishes a sociopolitical

TABLE 1. Genotype and allele frequencies in each population

LCT-13910C>TGenotype count Allele

frequencyPopuation CC CT TT T

Mapuche 26 3 0 0.05Araucan�ıa Mestizos 80 29 6 0.125Total Araucan�ıa region 106 32 6 0.15

TABLE 2. Fst values and associated P-value of each pairwisecomparisons

Mapuche Santiago Mestizos

Araucan�ıa Mestizos 0.049 (P 5 0.032*) 0.002 (P 5 0.194)Santiago Mestizos 0.074 (P < 0.001*)

* P-value < 0.05

TABLE 3. Food frequency consumption of dairy products

Food type2 or

more/day 1/day 2–3/week 1/week 1–3/month 2–10 /year Never

Community-produced milk 5 3 2 6 0 0 13Industrial milk 7 1 2 2 0 0 17Other types of milk 0 0 0 3 0 0 26Yogurt 2 8 9 3 0 0 7Cow’s milk cheese 2 7 18 1 0 0 1Other types of cheeses 0 1 0 0 0 0 28Cream or Ice cream 0 2 3 17 0 0 7Milk desserts 0 6 9 6 0 0 8

Number of individuals in each category.

484 C.I. FERN�ANDEZ AND S.V. FLORES

American Journal of Physical Anthropology

organization of the land and a family structure (Faron,1997) that could limit immigration to their area and pre-sumably the chance of admixture.

The high frequency of LNP shown by the Mapuchepopulation led us to consider other variables presumablyassociated with this biological trait. First, it is notablethat a high proportion of the LNP individuals (49%) donot report adverse symptoms after ingestion of dairyproducts. This situation observed in the Mapuche is par-tially in agreement with a study in another ethnic popu-lation on Tokelau Island (Cheer and Allen 1997). In thatstudy, most of the LNP individuals, diagnosed by hydro-gen breath test, did not exhibit symptoms. However,these cases are opposed to the results of most of thestudies on urban populations (Casellas et al., 2010;Tomba et al., 2012), in which other causes for the symp-toms resulting from secondary hypolactasia should beconsidered (see Saavedra and Perman, 1989; Peuhkuri,2000). Further analyses using tolerance tests along withgenotyping for LP in Mapuche populations should allowdetermining whether symptoms are due to the LNPstate or to alternative causes.

Although most of the individuals (90%) attributed apositive value to dairy products and their consumption,effective dairy intake among the Mapuche contrastswith this widespread statement. Dairy average ingestionis far below the Chilean standard nutritional recommen-dations (Olivares and Zacar�ıas, 2013) and our resultsare in agreement with other studies of Mapuche popula-tions from Chile (Peredo and Barrera, 2005; Schnettleret al., 2010) and Argentina (Ferrari et al., 2004); bothpopulations showing very low dairy consumption andcalcium intake.

Among biological variables that could restrict dairyconsumption, lactose intolerance seems to be the mostcommon (Khabarova et al., 2011; Bailey et al., 2013). Inour study regarding the causes that could explain lowdairy consumption, the most frequent answer chosen byindividuals was symptoms. Because of the symptomsreferred to by lactose intolerant individuals, the LP/LNPstate determines specific food patterns and behavioramong populations (Carroccio et al., 1998; Jackson andSavaiano, 2001; Obermayer-Pietsch et al., 2004).

Tradition and cultural practices also could contributeto explain low dairy consumption, as it was mentionedby the majority of the Mapuche individuals. Nowadayskeeping cattle is uncommon due to scarcity of land, thelogging industry boom and low incomes of Mapuche peo-ple, both in part as a consequence of establishment onnative reservations (CONADI, 2003). Thus milking prac-tices are still ignored; besides, dairy food has not beenpart of their traditional diet.

In Chile there is a tendency to a progressive decreaseof dairy product ingestion toward lower socioeconomiclevels (MINSAL, 2011). This tendency may be attributedto differences in income, experience of lactose intoler-ance or both. Interestingly, the Mapuche population is atthe lowest socioeconomic level in Chile (Cerda, 2009)and also shows the highest prevalence of LNP.

Several studies have shown an association betweenLNP state, avoidance of dairy intake and a prevalence ofbone mineral density diseases (Newcomer et al., 1978;Jackson and Savaiano, 2001; Obermayer-Pietsch et al.,2004; Laaksonen et al., 2009). In a study by Ponce et al.(2002) it has been shown that Mapuche women have thehighest prevalence of osteopenia and osteoporosis amongpopulations in the world. The high frequencies of LNP

and avoidance of dairy food may be one of the causes ofthe high prevalence of bone mineral density diseases inthis population.

Lactase persistence, dairy intake, and putative associ-ated pathologies have not been studied simultaneouslyin Amerindian populations. Future studies should focuson the relationship of socio-cultural and biological fac-tors affecting the nutritional status and bone health ofliving populations. These findings could contribute toevaluate the appropriateness of public policies on foodand nutrition in order to consider cultural and biologicalvariation of Amerindian populations.

ACKNOWLEDGMENTS

We wish to express our gratitude to Mauricio Moraga,Ricardo Verdugo, Sebasti�an Krapivka and Nicol�as Mon-talva for their comments during the development of thiswork, as well as to two anonymous reviewers for theirsuggestions and criticisms, which helped to improveour article. Last but not least, we warmly acknowledgethe Mapuche communities (Juan Huenchual, ManuelLlancam�an and Mahuidanche) and all participatingdonors in this study, without whom this study would nothave been possible.

LITERATURE CITED

Araneda J, Amigo H, Bustos P. 2010. Caracter�ısticasalimentar�ıas de adolescentes chilenas ind�ıgenas y noind�ıgenas. Arch Latinoam Nutr 60:30–35.

Arcos-Burgos M, Herrera P, Pandey J, Valenzuela C. 2004.An�alisis de mezcla gen�etica. In: Rothhammer F, Llop E, edi-tors. Poblaciones chilenas. Cuatro d�ecadas de investigacionesbioantropol�ogicas. Santiago, Chile: Universitaria Publisher. p241–267.

Arola H, Tamm A. 1994. Metabolism of lactose in the humanbody. Scand J Gastroenterol Suppl 202:21–25.

Bailey RK. 2013. Lactose intolerance and health disparitiesamong African Americans and Hispanic Americans: anupdated consensus statement. J Natl Med Assoc 105:112–127.

Bengoa J. 2007. Historia de los antiguos mapuches del sur:Desde antes de la llegada de los espa~noles hasta las paces deQuil�ın. Santiago, Chile: Catalonia Publisher.

Bengoa J. 2000. Historia del pueblo mapuche: Siglos XIX y XX.Santiago, Chile: LOM Publisher.

Bersaglieri T, Sabeti P, Patterson N, Vanderploeg T, SchaffnerS, Drake J, Rhodes M, Reich D, Hirschhorn J. 2004. Geneticsignatures of strong recent positive selection at the lactasegene. Am J Hum Genet 74:1111–1120.

Bulh~oes A, Goldani H, Oliveira F, Matte U, Mazzuca R, SilveiraT. 2007. Correlation between lactose absorption and the C/T-13910 and G/A-22018 mutations of the lactase-phlorizinhydrolase (LCT) gene in adult-type hypolactasia. Braz J MedBiol Res 40:1441–1446.

Carrasco E, P�erez F, Angel B, Albala C, Santos JL, Larenas G,Montalvo D. 2004. Prevalencia de diabetes tipo 2 y obesidaden dos poblaciones abor�ıgenes de Chile en ambiente urbanoRev M�ed Chile 132:1189–1197.

Carroccio A, Montalto G, Cavera G, Notarbatolo A. 1998. Lac-tose intolerance and self-reported milk intolerance: relation-ship with lactose maldigestion and nutrient intake. J Am CollNutr 17:631–636.

Casellas F, Aparici A, Casaus M, Rodr�ıguez P, Malagelada JR.2010. Subjective perception of lactose intolerance does notalways indicate lactose malabsorption. Clin GastroenterolHepatol 8:581–586.

Cerda RA. 2009. Situaci�on socioecon�omica reciente de losmapuches en la regi�on de la Araucan�ıa. Estud Publicos 113:27–107.

LACTASE NONPERSISTENCE AND DIARY INTAKE IN CHILE 485

American Journal of Physical Anthropology

Cheer S, Allen J. 1997. Lactose digestion capacity and perceivedsymptomatic response after dairy product consumption inTokelau Island migrants. Am J Hum Biol 9:2333–2246.

[CONADI] Corporaci�on Nacional de Desarrollo Ind�ıgena. 2003.Informe de la Comisi�on Verdad Hist�orica y Nuevo Trato. San-tiago, Chile: Pehu�en publishers. 624 p.

Enattah NS, Sahi T, Savilahti E, Terwilliger JD, Peltonen L,J€arvel€a I. 2002. Identification of a variant associated withadult-type hypolactasia. Nat Genet 30:233–237.

Excoffier L, Laval G, Schneider S. 2005. Arlequin (version 3.0):An integrated software package for population genetics dataanalysis. Evol Bioinform Online 1:47–50.

Faron LC. 1997. Perfil de la estructura social Mapuche. In:Ant€upai~namko, moral y ritual mapuche. Santiago, Chile:Mundo. p 19–49.

Ferrari MA, Morazzani F, Pinotti LV. 2004. Patr�on alimentariode una comunidad aborigen de la Patagonia Argentina. RevChil Nutr 31:110–117.

Friedrich DC, Santos SE, Ribeiro-Dos-Santos AK, Hutz MH.2012a. Several different lactase persistence associated allelesand high diversity of the lactase gene in the admixed brazil-ian population. PLoS One 7:e46520.

Friedrich DC, Callegari-Jacques SM, Petzl-Erler ML, TsunetoL, Salzano FM, Hutz MH. 2012b. Stability or variation? Pat-terns of lactase gene and its enhancer region distributions inBrazilian Amerindians. Am J Phys Anthropol 147:427–432.

Gerbault P, Moret C, Currat M, Sanchez-Mazas A. 2009. Impactof selection and demography on the diffusion of lactase per-sistence. PLoS One 4:e6369.

[INE] Instituto Nacional de Estad�ısticas (Chile). 2004 Dec.Migraci�on Inter e Intra Regional: Movimiento MigratorioCenso Abril 2002 [Internet]. Regi�on del B�ıo B�ıo (Chile). [cited2014 Mar 12]. Available at: http://www.inebiobio.cl/archivos/files/pdf/poblacion/Migracion_Regional.pdf.

[INE] Instituto Nacional de Estad�ısticas (Chile). 2014. ResultadosXVIII Censo de poblaci�on 2012. Santiago, Chile. [cited 2014Mar 16]. Available at: http://www.censo.cl/contenido/documentos/poblacion_resultado_censo2012.pdf.

Ingram CJE, Elamin MF, Mulcare CA, Weale ME, Tarekegn A,Raga TO, Bekele E, Elamin FM, Thomas MG, Bradman N,Swallow DM. 2007. A novel polymorphism associated withlactose intolerance in Africa: multiple causes for lactase per-sistence. Hum Genet 120:779–788.

Ingram CJE, Mulcare CA, Itan Y, Thomas MG, Swallow DM.2009a. Lactose digestion and the evolutionary genetics of lac-tase persistence. Hum Genet 124:576–591.

Ingram CJE, Raga TO, Tarekegn A, Browning SL, Elamin MF,Bekele E, Thomas MG, Weale ME, Bradman N, Swallow DM.2009b. Multiple rare variants as a cause of a common pheno-type: several different lactase persistence associated alleles ina single ethnic group. J Mol Evol 69:579–588.

Jensen TG, Liebert A, Lewinsky R, Swallow DM, Olsen J,Troelsen JT. 2011. The 14010*C variant associated with lac-tase persistence is located between an Oct-1 and HNF1a

binding site and increases lactase promoter activity. HumGenet 130:483–493.

Jackson KA, Savaiano DA. 2001. Lactose maldigestion, calciumintake and osteoporosis in African-, Asian-, and Hispanic-Americans. J Am Coll Nutr 20:198–207.

Jones BL, Raga TO, Liebert A, Zmarz P, Bekele E, DanielsenET, Olsen AK, Bradman N, Troelsen JT, Swallow DM. 2013.Diversity of lactase persistence alleles in Ethiopia: signatureof a soft selective sweep. Am J Hum Genet 93:538–544.

Khabarova Y, Tornianen S, Tuomisto S, J€arvel€a I, Karhunen P,Mattila K. 2011. Lactase non-persistent genotype influencesmilk consumption and gastrointestinal symptoms in NorthernRussians. BMC Gastroenterol 11:124.

Laaksonen MM, Impivaara O, Siev€anen H, Viikari JS,Lehtim€aki TJ, Lamberg-Allardt CJ, K€arkk€ainen MU,V€alim€aki M, Heikkinen J, Kr€oger LM, Kr€oger HP, JurvelinJS, K€ah€onen MA, Raitakari OT. 2009. Associations of geneticlactase non-persistence and sex with bone loss in youngadulthood. Bone 44:1003–1009.

Lacassie Y, Weinberg R, M€onckeberg F. Poor predictability oflactose malabsorption from clinical symptoms for Chileanpopulations. 1978. Am J Clin Nutr 31:799–804.

Lewinsky R, Jensen T, Mller J, Stensballe A, Olsen J, TroelsenJ. 2005. T 213910 DNA variant associated with lactase per-sistence interacts with Oct-1 and stimulates lactase promoteractivity in vitro. Hum Mol Genet 14:3945–3953.

Lomer MC, Parkes GC, Sanderson JD. 2008. Review article: lac-tose intolerance in clinical practice-myths and realities. Ali-ment Pharmacol Ther 27:93–103.

Mattar R, Monteiro MS, Villares CA, Santos AF, Silva JMK,Carrilho FJ. 2009. Frequency of LCT-13910C>T single nucle-otide polymorphism associated with adult-type hypolactasia/lactase persistence among Brazilians of different ethnicgroups. Nutr J 8:46.

Mendoza Torres E, Varela Prieto LL, Villarreal Camacho JL,Villanueva Torregroza DA. 2012. Diagnosis of adult-typehypolactasia/lactase persistence: genotyping of single nucleo-tide polymorphism (SNP C/T-13910) is not consistent withbreath test in Colombian Caribbean population. Arq Gastro-enterol 49:5–8.

[MINSAL] Ministerio de Salud (Chile). 2011. Encuesta Nacionalde Consumo Alimentario (ENCA) 2010–2011.

Morales E, Azocar L, Maul X, Perez C, Chianale J, Miquel JF.2011. The European lactase persistence genotype determinesthe lactase persistence state and correlates with gastrointesti-nal symptoms in the Hispanic and Amerindian Chilean popu-lation: a case-control and population-based study. BMJ Open1:e000125.

Newcomer AD, Hodgson SF, McGill DB, Thomas PJ. 1978. Lac-tase deficiency: prevalence in osteoporosis. Ann Intern Med89:218–220.

Obermayer-Pietsch BM, Bonelli CM, Walter DE, Kuhn RJ,Fahrleitner-Pammer A, Berghold A, Goessler W, Stepan V,Dobnig H, Leb G, Renner W. 2004. Genetic predisposition foradult lactose intolerance and relation to diet, bone density,and bone fractures. J Bone Miner Res 19:42–47.

Olivares S, Zacar�ıas I (Instituto de Nutrici�on y Tecnolog�ıa delos Alimentos-INTA, Universidad de Chile, Santiago deChile). 2013. Estudio para revisi�on y actualizaci�on de lasgu�ıas alimentarias para la poblaci�on chilena. Informe Final16 Mayo 2013. Santiago, Chile: Ministerio de Salud. 140p.[cited 2014 Mar 12]. Available at: http://web.minsal.cl/portal/url/item/dde0bc471a56a001e040010165012224.pdf.

Osier MV, Cheung K-H, Kidd JR, Pakstis AJ, Miller PL. 2002.ALFRED: an allele frequency database for anthropology. AmJ Phys Anthropol 119:77–83.

Peredo SP, Barrera CP. 2005. La monoculturizaci�on del espacionatural y sus consecuencias socioculturales en una comuni-dad rural ind�ıgena del sur de Chile. Revista de Antropolog�ıaExperimental 5:1–10.

Peuhkuri K. 2000. Lactose, Lactase and Bowel Disorders:Reducing hypolactasia-related gastrointestinal symptoms byimproving the digestibility of lactose [DPhil thesis]. Finland:University of Helsinki. Available at: http://ethesis.helsinki.fi/julkaisut/laa/biola/vk/peuhkuri/lactose.html. Accessed 2014Mar 12.

Pinto J. 2011. Ganader�ıa y empresarios ganaderos de la Arau-can�ıa, 1900–1960. Historia (Santiago) 44:369–400.

Ponce L, Larenas G, Riedemann P. Alta prevalencia de osteopo-rosis en mujeres mapuches postmenop�ausicas asintom�aticas.Rev Med Chile 130:1365–1372.

Primo AT. 1992. El ganado bovino ib�erico en las Am�ericas: 500a~nos despu�es. Arch Zootec 41:421–431.

Quinque D, Kittler R, Kayser M, Stoneking M, Nasidze I.2006.Evaluation of saliva as a source of human DNA for pop-ulation and association studies. Anal Biochem 353:272–277.

R Core Team 2012. R: A Language and Environment for Statis-tical Computing. R Foundation for Statistical Computing.Vienna, Austria. ISBN 3-900051-07-0 URL. Available at:http://www.R-project.org/

Romero L. 1984. Urbanizaci�on y sectores populares: Santiago deChile, 1830-1875. EURE 11:55–74.

486 C.I. FERN�ANDEZ AND S.V. FLORES

American Journal of Physical Anthropology

Rouse JE. 1977. The criollo: Spanish cattle in the Americas.Norman, USA: University of Oklahoma Press, 303 p.

Saavedra JM, Perman, JA. 1989. Current concepts in lactosemalabsorption and intolerance. Annu Rev Nutr 9:475–502.

Sahi T, Isokoski M, Jussila J, Launiala K, Py€or€al€a K. 1973.Recessive inheritance of adult-type lactose malabsorption.Lancet 302:823–826.

Schnettler B, Huaiqui~nir V, Mora M, Miranda H, Sep�ulveda J,Denegri M. 2010. Diferencias �etnicas y de aculturaci�on en elconsumo de alimentos en la regi�on de la Araucan�ıa, Chile.Rev Chil Nutr 37:31–40.

Stahl PW. 2008. Animal Domestication in South America. In:Handbook of South American archaeology. New York:Springer. p 121–130.

Tishkoff SA, Reed FA, Ranciaro A, Voight BF, Babbitt CC,Silverman JS, Powell K, Mortensen HM, Hirbo JB, OsmanM, Ibrahim M, Omar SA, Lema G, Nyambo TB, Ghori J,

Bumpstead S, Pritchard JK, Wray GA, Deloukas P. 2007.Convergent adaptation of human lactase persistence in Africaand Europe. Nat Genet 39:31–40.

Tomba C, Baldassarri A, Coletta M, Cesana BM, Basilisco G.2012. Is the subjective perception of lactose intolerance influ-enced by the psychological profile? Aliment Pharmacol Ther36:660–669.

Torniainen S, Parker MI, Holmberg V, Lahtela E, Dandara C,Jarvela I. 2009. Screening of variants for lactase persistence/nonpersistence in populations from South Africa and Ghana.BMC Genet 10:31.

Vesa TH, Marteau P, Korpela R. 2000. Lactose intolerance.J Am Coll Nutr 19:165–175.

Wright S. 1978. Evolution and the genetics of populations, vol4. Variability within and among natural populations. Chicago,Illinois: University of Chicago Press.

LACTASE NONPERSISTENCE AND DIARY INTAKE IN CHILE 487

American Journal of Physical Anthropology