Investigation of androgen receptor CAG repeats length in polycystic ovary syndrome diagnosed using the new international evidence-based guideline

Abstract

Background: To study whether CAG repeat polymorphism of androgen receptor (AR) contributes to the risk of polycystic ovarian morphology (PCOM) with antral follicle count (AFC) ≥ 20 in the context of new international guideline of polycystic ovary syndrome (PCOS).

Methods: Blood of 109 PCOS cases and 61 controls were collected for the measurement of AR CAG repeats length by sequencing. The mean number and frequency distribution of CAG repeats length were observed. Detailed analysis was conducted by dividing PCOS cases into low AFC group (L-AFC, AFC < 20) and high AFC group (H-AFC, AFC ≥ 20) according to the new international evidence-based guideline.

Results: The portion of individuals with lower CAG repeats length in H-AFC group was significantly larger than those with higher CAG repeats length. Logistic model revealed individuals with lower CAG length tended to develop H-AFC.

Conclusion: Lower CAG repeats length in the AR gene of PCOS cases increases risk of PCOM.

Keywords: Androgen receptor; CAG repeats; Genetic polymorphism; Polycystic ovarian morphology; Polycystic ovary syndrome.