IRS1 and gestational diabetes: Falluca et al. [28] verified a frequency of 11.0% of the polymorphism in women with GDM, 9.8% in gestational impaired glucose tolerance (G-IGT), and 7.9% in women with a negative glucose-challenge test (NGT) result, suggesting that the IRS-1 genetic polymorphism is involved in the occurrence of gestational diabetes, as well as type 2 diabetes mellitus.