IRS1 and diabetes mellitus: 28 An investigation of the relationships between the 2228570 C>T and 1544410 A>G polymorphisms of the VDR gene and MS in adults suggests that they could influence insulin release and insulin resistance, but was unable to determine their influence on components of MS. 29 A study by Gelaleti et al. 30 evaluated presence of the Arg972 polymorphism of the IRS-1 gene in pregnant women with diabetes or mild gestational hyperglycemia and their newborn infants.