Over the past several decades, numerous studies have identified type 2 diabetes mellitus (T2DM) [72,73,74,75,76,77,78,79,80] and obesity [81,82,83,84,85,86,87,88,89,90,91,92] as determinant factors associated with impaired insulin clearance. The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.