CRTC1 and obesity due to melanocortin 4 receptor deficiency: For example, of the four loci discovered by the recently discussed GWAS in BF% (in or near COBLL1/GRB14, IGF2BP1, PLA2G6, CRTC1) [52] and in the most recent GWAS of obesity as measured by BMI [21] only a very small number of these overall obesity loci exhibited sexual dimorphism (approximately 3–5%) [21,52].