genome-wide data into social science research through the application of GWAS and GWGEI methods to a phenotype with both genetic and environmental influences. One of the primary goals of this article is to evaluate the relevance of the current GxE models for a GWGEI study using a highly heritable phenotype (namely, body mass index (BMI)) and an established environmental determinant of BMI (education) with a well-characterized and reasonably sized (n = 1,877) sample of adults (the third generation of the FHS). We use college education as our measure of the environment because it is a valid and reliable indicator of socioeconomic position owing to its association with job status, residential quality, health, and health-related behaviors (Pampel et al. 2010). Using current genome-wide methods (Moreno-Macias et al. 2010), we examine the association between 260,402 single nucleotide polymorphisms (SNPs) and BMI, the interaction between each SNP and education, and separate GWAS models for college graduates and non–college graduates. We provide an overview of the statistical and substantive problems with these analyses, including population stratification and gene-environment correlation.
