Sanger sequencing across the KCNQ1 region in the IS1 and IS2 parental lines revealed that IS1 is homozygous for the KCNQ1 non-risk alleles and IS2 is heterozygous for the KCNQ1 type 2 diabetes risk alleles. This evidence concerns the gene KCNQ1 and type 2 diabetes mellitus.