Background: Earlier studies on the role of germline variations in the disproportionate higher burden of prostate cancer in men of African ancestry have been largely unrewarding. However, the successful replication of recent genome-wide association findings implicating some regions of chromosome 8q24 in the disparate prostate cancer susceptibility in men of European and African ancestry have been encouraging. This case-control study was designed to evaluate the association between germline variations in chromosome 8q24 and prostate cancer risk in Afro-Caribbean Tobago men, a population of predominantly West African ancestry.
Methods: High molecular weight genomic DNA was isolated from blood clots using Qiagen kits. Genotyping was performed on genomic DNA using a pre-designed TaqMan SNP assay according to the manufacture's protocol on a 7900HT Fast Real-Time PCR system (Applied Biosystems, Foster City, CA).
Results: SNP rs16901979 in region 2 was associated with significantly increased risk of prostate cancer (OR = 1.41, 95% confidence interval [CI] 1.02-1.95, P = 0.04) with the risk stronger in men with early-onset prostate cancer (OR = 2.37, 95% CI 1.40-3.99, P = 0.001). There was a tendency towards significantly increased risk for SNPs rs1447295 and rs6983267 in men with early-onset prostate cancer.
Conclusions: The replication of the association of chromosome 8q24 variants with increased prostate cancer risk in Tobago men and the higher frequency of the risk alleles in controls in populations of African ancestry further strengthens the possible role of this genomic region in the disproportionate higher burden of prostate cancer in men of African ancestry.
Copyright © 2011 Wiley-Liss, Inc.