The in vitro studies suggest that 2-aminoadipate had an effect on insulin secretion in pancreatic β-cells and isolated islets (Wang et al., 2013) and the positive associations between 2-aminoadipate levels and type 2 diabetes risk in human may be due to the development of insulin resistance secondary to chronic hyperinsulinemia (Newgard, 2017; Wang et al., 2013). Here, INS is linked to type 2 diabetes mellitus.