Genetical Research



Sex-specific selection on the human X chromosome?


PATRICIA BALARESQUE a1a2c1, BRUNO TOUPANCE a1, QUINTANA-MURCI LLUIS a3, BRIGITTE CROUAU-ROY a2 and EVELYNE HEYER a1c2
a1 Unité Eco-Anthropologie MNHN/CNRS/P7 UMR5145, Paris, France
a2 Laboratoire Evolution et Diversité Biologique, Toulouse, France
a3 CNRS URA1961, Institut Pasteur, Paris, France

Article author query
balaresque p   [PubMed][Google Scholar] 
toupance b   [PubMed][Google Scholar] 
lluis qm   [PubMed][Google Scholar] 
crouau-roy b   [PubMed][Google Scholar] 
heyer e   [PubMed][Google Scholar] 

Abstract

Genes involved in major biological functions, such as reproductive or cognitive functions, are choice targets for natural selection. However, the extent to which these genes are affected by selective pressures remains undefined. The apparent clustering of these genes on sex chromosomes makes this genomic region an attractive model system to study the effects of evolutionary forces. In the present study, we analysed the genetic diversity of a X-linked microsatellite in 1410 X-chromosomes from 10 different human populations. Allelic frequency distributions revealed an unexpected discrepancy between the sexes. By evaluating the different scenarios that could have led to this pattern, we show that sex-specific selection on the tightly linked VCX gene could be the most likely cause of such a distortion.

(Received August 12 2003)
(Revised March 12 2004)


Correspondence:
c1 Equipe de Génétique des populations, Musée de l'Homme 17, place du Trocadéro, 75116 Paris, France. Tel: +33 1 44057253. Fax: +33 1 44057241. e-mail: heyer@mnhn.fr
c2 Equipe de Génétique des populations, Musée de l'Homme 17, place du Trocadéro, 75116 Paris, France. Tel: +33 1 44057253. Fax: +33 1 44057241. e-mail: balares@mnhn.fr


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