INS and type 2 diabetes mellitus: By the year 2000 Candidate gene studies had identified a number of genes to be associated with Type 2 diabetes although the approach was being criticized for lacking roughness and sensitivity as some genes which were already known to have an impact on insulin activities were not confirmed in population studies as they showed association and having only investigated a limited number of variants and genes in limited, small or unmatched populations that made it difficult to replicate weak associations that were detected (68, 69).