Figure 2From: Testing gene-environment interactions in gene-based association studiesJoint testing of gene-environment interaction and main effects. The Q-Q plots compare the distribution of association –log10p-values for gene KDR (left panel) and FLT1 (right panel) derived from model (10) (circles) and model (14) (triangles) adjusted for 15 principal components (solid triangles and circles) or 200 principal components (open triangles and circles).Back to article page