Among those genes are insulin receptors, fatty acid synthase, lipoprotein lipase, adiponectin, leptin, acetyl-CoA carboxylase beta, and fatty acid binding protein 4 (FABP4, Figure 1B) [22], the latter being a new player connecting obesity with breast cancer development [23]. The gene discussed is INSR; the disease is obesity due to melanocortin 4 receptor deficiency.