The sex-specific genetic architecture of quantitative traits in humans.

Mapping genetically complex traits remains one of the greatestchallenges in human genetics today. In particular, gene-environment and gene-gene interactions, genetic heterogeneityand incomplete penetrance make thorough genetic dissectionof complex traits difficult, if not impossible. Sex could beconsidered an environmental factor that can modify bothpenetrance and expressivity of a wide variety of traits. Sex iseasily determined and has measurable effects on recognizablemorphology; neurobiological circuits; susceptibility toautoimmune disease, diabetes, asthma, cardiovascular andpsychiatric disease; and quantitative traits like blood pressure,obesity and lipid levels, among others. In this study, weevaluated sex-specific heritability and genome-wide linkagesfor 17 quantitative traits in the Hutterites. The results of thisstudy could have important implications for mapping complextrait genes.Recently, it was found that genes on the X chromosome showastounding variation in expression and action between males andfemales