Linkage disequilibrium between the androgen receptor gene CAG and GGC repeats in the African-American population.

African-American men are at an increased risk of developing prostate cancer when compared with other racial and ethnic groups. In addition, African-Americans display a greater propensity for developing aggressive prostate cancer. There are multiple etiologic factors that likely contribute to the development of prostate cancer; however, one potential factor that may explain differences of prostate cancer risk among ethnic and racial groups is the androgen receptor (AR) gene. Studies have showed that there is correlation between two polymorphic microsatellite regions of the AR receptor gene and its transactivational activity. The CAG and GGC repeats both have been implicated as important loci for variation in differential androgen receptor activity. This review analyzes the available data regarding variation of the CAG and GGC repeat sequences among different racial and ethnic populations, and the implications of these variations for prostate cancer risk.