The association between androgen receptor gene CAG polymorphism and polycystic ovary syndrome: a case-control study and meta-analysis
- 271 Downloads
Many studies have been carried out to confirm the relationship between androgen receptor gene CAG repeat polymorphism and polycystic ovary syndrome (PCOS), without consistent results. Hence we conducted the current study to research this relationship.
224 Chinese Han women with PCOS and 223 in vitro fertilization and embryo transplantation (IVF-ET) infertile women with tubal factor or male infertility served as the controls were recruited in our study. PCR-based assays were applied to genotype the (CAG)n repeat alleles. A meta-analysis including 1,536 PCOS patients and 1,807 controls was conducted to produce a pooled estimate.
We observed that the CAG bi-allelic mean lengths were similar in PCOS patients and controls (22.65 ± 2.5 vs. 23.09 ± 2.1, P = 0.116). When CAG bi-allelic were divided into two categories (mean repeats ≤22, >22), the short AR-CAG bi-allelic showed more frequent in PCOS group than in controls (56.25 % vs 29.14 %, P < 0.001). Further analysis presented that, in PCOS, there was a lower mean CAG repeat lengths in mean bi-allelic lengths (22.3 ± 2.5 vs. 23.9 ± 2.2, P = 0.008) and long bi-allelic lengths (24.3 ± 1.4 vs. 25.9 ± 1.6, P = 0.05) among patients with testosterone less than 0.7 ng/ml compared with those whose testosterone was more than 0.7 ng/ml. Besides, the testosterone were positively correlated with the CAG polymorphism (r = 0.237, P = 0.008), which accorded with our meta-analysis results.
The distribution of AR-CAG allele differed between PCOS patients and controls, and polymorphism of CAG repeat lengths may contribute to hyperandrogenism in PCOS.
KeywordsPCOS Androgen receptor CAG repeats Meta-analysis
We are grateful to the subjects participating in this study. This work was partially supported by grants from the no. National Natural Science Foundation of China (No.31371277; No.81102516) and the Science and Technology Research Program of Hunan Province of China (2012FJ4296).
Conflict of interest
The authors declare that they have no conflict of interest.
- 1.Stein IF, Leventhal ML. Amenorrhea associated with bilateral polycystic ovaries. Am J Obstet Gynecol. 1935;29:181–91.Google Scholar
- 3.Wild RA, Carmina E, Diamanti-Kandarakis E, Dokras A, Escobar-Morreale HF, Futterweit W, et al. Assessment of cardiovascular risk and prevention of cardiovascular disease in women with the polycystic ovary syndrome: a consensus statement by the Androgen Excess and Polycystic Ovary Syndrome (AE-PCOS) Society. J Clin Endocrinol Metab. 2010;95(5):2038–49.PubMedCrossRefGoogle Scholar
- 4.Fux Otta C, Fiol de Cuneo M, Szafryk de Mereshian P. Polycystic ovary syndrome: physiopathology review. Rev Fac Cien Med (Cordoba, Argentina). 2013;70(1):27–30.Google Scholar