Association of polymorphisms within androgen receptor, 5alpha-reductase, and PSA genes with prostate volume, clinical parameters, and endocrine status in elderly men

Abstract

Background: The aim of this study was to assess the impact of polymorphisms of three genes within the androgen pathway on prostate volume, clinical parameters, and endocrine status.

Methods: Elderly men with lower urinary tract symptoms underwent clinical and endocrine work-up. In parallel, polymorphisms within the 5alpha-reductase gene (SRD5A2 V89L and A49T), the androgen receptor gene (AR; number of CAG repeats), and the prostate specific antigen (PSA) gene (A --> G substitution at position-158) were determined by polymerase chain reaction and restriction-length polymorphism analysis by using DNA from peripheral blood.

Results: A total of 190 men (66.5 +/- 9.2 yr) were analyzed. The number of CAG repeats within the AR and the PSA polymorphism revealed no associations to clinical and endocrine parameters. Individuals carrying the mutated SRD5A2 A49T allele (5.3% of the total population) had larger prostates (54.1 vs. 39.3 ml), higher PSA levels (12.2 vs. 4.3 ng/ml), and a 35% reduction in prostatic stroma/epithelial cell ratio. Men with the mutated SRD5A2 V89L gene had lower testosterone levels.

Conclusions: In contrast to prostate cancer, polymorphisms within AR and PSA genes do not seem to be of importance for benign prostatic hyperplasia. Polymorphisms within the 5alpha-reductase gene are interesting biomarkers for the development of benign prostatic hyperplasia and benign prostatic enlargement.