Furthermore, the 2-azabicyclo[3.1.0]hexane derivative of 3-hydroxyadamantylglycine, named Saxagliptin, is a pharmaceutical of the dipeptidyl peptidase IV (DPP-4) inhibitor class against type 2 diabetes mellitus and entered the market in 2009 (Figure 2) [16]. This evidence concerns the gene DPP4 and diabetes mellitus.