IGF1 and obesity due to melanocortin 4 receptor deficiency: Obesity-related genes were retrieved in the Digsee database and the top 15 obesity-related genes were selected as disease genes (Adipoq, Igf1, Fto, Hsd11b1, Tnf, Gh1, Mc4r, Lep, Pparg, Il6, Crp, Lepr, Pomc, Lpl, and Ghr1).