The role of SNPs in obesity therapy has been shown in some studies for genes like peroxisome proliferator-activated receptor gamma (PPARG) [5,6], matrix metalloproteinase 2 (MMP2), Perilipin-1 (PLIN1), and metalloproteinase inhibitor 4 (TIMP4) [6], while others did not show evidence for an association between SNPs and weight loss [7,8,9]. The gene discussed is TIMP4; the disease is obesity due to melanocortin 4 receptor deficiency.