Insulin gene variable number of tandem repeats regulatory polymorphism is not associated with hyperandrogenism in Spanish women☆

Abstract 

Objective: To determine if the insulin gene variable number of tandem repeats (VNTR) regulatory polymorphism is associated with hyperandrogenism in a population of Spanish women.

Design: Controlled clinical study.

Setting: Tertiary institutional hospital.

Patient(s): Ninety-six hyperandrogenic patients and 38 healthy control women.

Intervention(s): Whole blood and serum samples were collected during the follicular phase of the menstrual cycle.

Main Outcome Measure(s): Insulin gene VNTR regulatory polymorphism genotypes (classes I/I, I/III, and III/III alleles) and serum androgen levels. Insulin resistance was estimated from fasting glucose and insulin levels by using the homeostatic model assessment.

Result(s): The frequencies of VNTR genotypes were 45.5%, 43.3%, and 11.2% for I/I, I/III, and III/III alleles considering patients and controls as a whole. These frequencies were not statistically different in controls (47.4%, 34.2%, and 18.4%) and in patients (44.8%, 46.9%, and 8.3%).

Conclusion(s): Hyperandrogenism and the insulin gene VNTR regulatory polymorphism are not associated in Spanish women.

Keywords:  Variable number of tandem repeats, VNTR, insulin, -23/Hph I, polymorphism, polycystic ovary syndrome, hirsutism, hyperandrogenism