The rising prevalence of DM, particularly type 2 diabetes mellitus (T2DM), stems from a complex interplay of genetic predispositions—such as obesity, impaired postprandial insulin release, and damage to certain pancreatic β cells—and environmental factors, including obesity, poor dietary habits, physical inactivity, and aging (Młynarska et al., 2025). Here, INS is linked to obesity due to melanocortin 4 receptor deficiency.