It is a leptin receptor mutation that causes abnormal splicing and adipocyte-derived hormone leptin receptor defects, and the leptin receptor deficiency affects the hypothalamic reaction, which makes the mice appear hyperappetite, obese, hyperlipidemia, and insulin resistant, and the other symptoms are similar to those of patients with type 2 diabetes (Tesch and Lim, 2011). This evidence concerns the gene LEPR and type 2 diabetes mellitus.