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Variance components models for gene-environment interaction in quantitative trait locus linkage analysis.

Shaun Purcell·Pak Sham
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Abstract

Gene-environment interaction (G x E) is likely to be a common and important source of variation for complex behavioral traits. Gene-environment interaction, or genetic control of sensitivity to the environment, can be incorporated into variance components twin and sib-pair analyses by partitioning genetic effects into a mean part, which is independent of the environment, and a part that is a linear function of the environment. An approach described in a companion paper (Purcell, 2002) is applied to sib-pair variance components linkage analysis in two ways: allowing for quantitative trait locus by environment interaction and utilizing information on any residual interactions detected prior to analysis. As well as elucidating environmental pathways, consideration of G x E in quantitative and molecular studies will potentially direct and enhance gene-mapping efforts.

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Computer SimulationEnvironmentGenetic LinkageGenetics, BehavioralHumansModels, GeneticQuantitative Trait LociTwinsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.Twin Study

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Shaun Purcell, Pak Sham. 2002. Variance components models for gene-environment interaction in quantitative trait locus linkage analysis.. https://doi.org/10.1375/136905202762342035

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