INS and type 2 diabetes mellitus: Thus, to understanding the details of the pattern and characteristics of T2DM heritability in SSA, detailed studies with the focus on the genetic characteristics of familial T2DM pedigrees, glucose transport and tolerance mechanisms, as well as insulin secretion mechanisms among T2DM probands (considering the effect of biological ageing and environmental stressors on the expression of insulin signalling proteins) will be useful.