GC is a complex, heterogeneous disease arising from unique epidemiologic backgrounds, such as Helicobacter pylori infection [3], diet, smoking, obesity [4], host genetic mutation and instability [5], such as E-cadherin gene (CDH1), PALB2, BRCA1, and RAD51C mutations [6, 7]. The gene discussed is CDH1; the disease is obesity due to melanocortin 4 receptor deficiency.