Related Experiment Video
Updated: Jul 8, 2026

A Hyperandrogenic Mouse Model to Study Polycystic Ovary Syndrome
Published on: October 2, 2018
Androgen receptor gene CAG repeat polymorphism in women with polycystic ovary syndrome
Jin Ju Kim1, Seon Ha Choung, Young Min Choi
1Department of Obstetrics and Gynecology, Seoul National University College of Medicine, Seoul, South Korea.
Objective:
To evaluate the role of the androgen receptor (AR) gene CAG repeat in women with polycystic ovary syndrome (PCOS).
Design:
Case control study.
Setting:
University department of obstetrics and gynecology.
Patient(S):
Women with (n = 114) or without (n = 205) PCOS.
Intervention(S):
Peripheral blood sampling was done for DNA analysis and serum hormone measurements.
Main Outcome Measure(S):
CAG repeat length and serum androgen levels.
Result(S):
No statistically significant CAG repeat length differences were found between patients and controls. We conducted a detailed analysis after dividing PCOS patients according to their free testosterone levels. The high free testosterone group had a statistically significantly longer mean biallelic average (24.0 +/- 2.0 vs. 23.0 +/- 1.5), short (22.5 +/- 1.8 vs. 21.7 +/- 1.9), and long (25.5 +/- 2.9 vs. 24.4 +/- 1.9) allelic lengths than the normal free testosterone group. In PCOS patients, a statistically significant correlation was found between biallelic average length and free testosterone concentration, either unadjusted or after adjustment.
Conclusion(S):
The AR gene CAG repeat polymorphism may contribute to the serum concentration of free testosterone in PCOS patients. A subset of PCOS patients with relatively longer CAG repeats (less AR activity) tended to show a higher serum androgen concentration.
Related Concept Videos
Oogenesis
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase
Disorders of the Female Reproductive System
Pharmacogenetic Phenotypes: Alterations in Pharmacokinetics, Drug Targets and Biologic Milieu
Comparing Copy Number Variations and SNPs
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
Pharmacogenetics of Phase I Enzymes: Cytochrome P450 Isozymes

