IRS2 and obesity due to melanocortin 4 receptor deficiency: IRS2 (BMI ≥ 25: 8.8%, BMI < 25: 1.5%; p = 0.041) is a gene involved in PI3K signaling that is related to colorectal cancer 14, and it is also known to be at the center of pathophysiology in diabetes where the aberration of IRS may be a fundamental cause of the development of insulin resistance, obesity, β cell failure, and type 2 diabetes 35.