INS and type 1 diabetes mellitus: Thefrequency of the INS rs689 A allele was lower in the T1DM groupwhen compared with controls (P <0.0001), and the genotype frequencies of thisSNP also showed significant differences between the two groups (P <0.0001).After adjustments for T1DM high-risk HLA DR/DQ genotypes andrace, the rs689/INS A/A genotype remained associated withprotection against T1DM, as also observed in the additive and dominant models ofinheritance.