LEP and obesity due to melanocortin 4 receptor deficiency: Besides the six leptin-increasing SNPs, we also replicated the associations of other three loci in SEC16B, ITIH4 and ADCY3/RBJ with adiposity traits, but no relationship between the three loci and leptin levels was observed, suggesting the possible different mechanisms between these loci underlying the body weight regulation, and the specific mechanisms through which these loci affect BMI and obesity require further study.