Increased frequency of the DI genotype of the angiotensin-I converting enzyme and association of the II genotype with insulin resistance in polycystic ovary syndrome

Abstract

The polycystic ovary syndrome (PCOS) is a common and complex disease with unclear pattern of inheritance, characterized by an androgen excess, while hyperinsulinemia and insulin resistance (IR) are common features of the syndrome. The angiotensin I converting enzyme (ACE) insertion (I)/deletion (D) gene polymorphism was proved to be involved in many pathophysiological conditions, including hypertension and IR. The purpose of this study was to evaluate the involvement of the ACE gene polymorphism in the pathogenesis of PCOS. In a case-control association study involving 801 PCOS women and 266 healthy controls, hormonal determinations and ACE polymorphism genotyping were performed. The PCOS women were classified into three groups: Group A presented biochemical hyperandrogenism, combined with anovulation and polycystic ovarian morphology; Group B, clinical hyperandrogenism combined with anovulation and polycystic ovarian morphology; and Group C, chronic anovulation and polycystic ovarian morphology. A significant increase in the frequency of the DI genotype of the ACE polymorphism was detected in PCOS women as a whole (P=0.035), in PCOS Group A (P=0.039) and Group B (P=0.010), while there was no difference in Group C (P=0.939). Significant difference was also observed in hyperandrogenic PCOS women as a whole (Group A+B) (P=0.017). The II genotype was positively correlated with HOMA-IR and QUICKI and with fasting insulin and glucose/insulin ratio in these groups. The association study of the ACE I/D polymorphism in PCOS women demonstrates an increase in the DI genotype incidence and an association of the II genotype with IR.