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Bias in parameter estimates due to omitting gene-environment interaction terms in case-control studies.

ABSTRACT: Genetic studies are continuing to generate volumes and variety of data that can be used to examine the genetic effects. Often the effect of a genetic variant varies by nongenetic measures, what is traditionally defined as gene-environment interaction (G×E). If the G×E term is neglected, estimates of the main effects can be substantially biased. We derive a general and convenient approximation to the magnitude of bias in the estimates due to omitting the G×E term. We show that the approximation is reasonably accurate in finite samples. We then apply the approximation in a study of Alzheimer's disease.

SUBMITTER: Lobach I

PROVIDER: S-EPMC6239944 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Bias in parameter estimates due to omitting gene-environment interaction terms in case-control studies.

Lobach Iryna I

Genetic epidemiology 20181009 8

Genetic studies are continuing to generate volumes and variety of data that can be used to examine the genetic effects. Often the effect of a genetic variant varies by nongenetic measures, what is traditionally defined as gene-environment interaction (G×E). If the G×E term is neglected, estimates of the main effects can be substantially biased. We derive a general and convenient approximation to the magnitude of bias in the estimates due to omitting the G×E term. We show that the approximation i ...[more]

PMID: 30302820

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