In addition to uncovering a mechanism that can generate large-scale effects on correlation – specifically, cases where the targets of a given TF are constitutively repressed in one genotypic class, but dynamically regulated in another – this example is of interest because previous work has found evidence for converge of trans eQTL effects on RAP1GAP in whole blood (Fehrmann et al., 2011), and has also implicated RAP1 in the development of insulin resistance, inflammation, and obesity (Kaneko et al., 2016). This evidence concerns the gene RAP1GAP and obesity due to melanocortin 4 receptor deficiency.