Collectively, our analyses highlight a few variants with genome-wide significant marginal effects that may be strong candidates for G×E interactions owing to their strong concurrent variance heterogeneity P-values. For BMI, such SNPs are also overrepresented in the nominally significant part of the Pv distribution. FTO is an excellent example, as it conveys strong marginal effects , exhibits high between-genotype heterogeneity here (Tables 2 and 3 and Fig 1B) and elsewhere , and reportedly interacts with physical activity, diet and other lifestyle exposures  and is associated with macronutrient intake .