Insulin gene polymorphism in women with polycystic ovary syndrome.

Insulin resistance is one of the main characteristics of polycystic ovary syndrome (PCOS) and is probably genetically predisposed. Possible associations of variable nucleotide tandem repeat (VNTR) polymorphism of the insulin gene (INS) with insulin resistance and PCOS in Slovene patients were investigated. A total of 117 PCOS patients and 108 age-matched female controls were genotyped for the INS VNTR polymorphism using real-time polymerase chain reaction and measurement of appropriate biochemical and clinical parameters. Serum fasting insulin (I(0)) levels and the homeostasis model assessment index were significantly elevated in PCOS patients compared with controls. Class III INS VNTR alleles were significantly more frequent in the PCOS group. The interaction between body mass index and INS VNTR genotype was a significant predictor of serum I(0) level. The interaction of obesity and the III/III INS VNTR genotype might be a risk factor for the development of PCOS.