title: Evidence of genotypic adaptation to the exposure to volcanic risk at the dopamine receptor DRD4 locus.
abstract: Humans have colonized and adapted to extremely diverse environments, and the genetic basis of some such adaptations, for example to high altitude, is understood. In some cases, local or regional variation in selection pressure could also cause behavioural adaptations. Numerous genes influence behaviour, such as alleles at the dopamine receptor locus D4 (DRD4), which are associated with attitude toward risk in experimental settings. We demonstrate genetic differentiation for this gene, but not for five unlinked microsatellite loci, between high- and low risk environments around Mount Merapi, an active volcano in Java, Indonesia. Using a behavioural experiment, we further show that people inhabiting the high risk environment are significantly more risk averse. We provide evidence of a genetic basis for this difference, showing that heterozygotes at the DRD4 locus are more risk averse than either homozygotes. In the high risk environment, allele frequencies are equilibrated, generating a high frequency of heterozygotes. Thus it appears that overdominance (i.e. selective advantage of heterozygotes) generates negative frequency dependent selection, favouring the rarer allele at this locus. Our results therefore provide evidence for adaptation to a marginal habitat through the selection of a neurocognitive trait with a genetic basis.
authors.affiliation: Institute of Evolutionary Sciences (ISEM), University of Montpellier, 2 Place Eugène Bataillon, 34090 Montpellier, France.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Faurie
authors.affiliation: Institute of Evolutionary Sciences (ISEM), University of Montpellier, 2 Place Eugène Bataillon, 34090 Montpellier, France.|Institute of Human Genetics, UPR 1142 CNRS, 141 rue de la Cardonille 34396 Montpellier, France.
authors.forename: Clement
authors.initials: C
authors.lastname: Mettling
authors.affiliation: Ecole Nationale du Génie de l'Eau et de l'Environnement, 1 Quai Koch, 67070 Strasbourg, France.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Ali Bchir
authors.affiliation: Department of Geography and Environmental Science, Faculty of Geography, Universitas Gadjah Mada, Yogyakarta, Indonesia.
authors.forename: Danang Sri
authors.initials: DS
authors.lastname: Hadmoko
authors.affiliation: Ecole Nationale du Génie de l'Eau et de l'Environnement, 1 Quai Koch, 67070 Strasbourg, France.
authors.forename: Carine
authors.initials: C
authors.lastname: Heitz
authors.affiliation: Department of Geography and Environmental Science, Faculty of Geography, Universitas Gadjah Mada, Yogyakarta, Indonesia.
authors.forename: Evi Dwi
authors.initials: ED
authors.lastname: Lestari
authors.affiliation: Institute of Evolutionary Sciences (ISEM), University of Montpellier, 2 Place Eugène Bataillon, 34090 Montpellier, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Raymond
authors.affiliation: Laboratoire Montpelliérain d'Economie Théorique et Appliquée, University of Montpellier, Bâtiment 26, 2 Place Pierre Viala, 34060 Montpellier, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Willinger
mesh_terms: D000483:Alleles; D002454:Cell Differentiation; D004247:DNA / Q000032:analysis; D005828:Genetics, Population; D005838:Genotype; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007214:Indonesia; D018895:Microsatellite Repeats; D011110:Polymorphism, Genetic; D050638:Receptors, Dopamine D4 / Q000235:genetics*; D012309:Risk-Taking; D018707:Volcanic Eruptions
chemical_list: C493599:DRD4 protein, human; D050638:Receptors, Dopamine D4; D004247:DNA