ASSOCIATION OF COMT AND CYP1B1 POLYMORPHISMS WITH PROSTATE CANCER RISK IN NIGERIAN MEN

Abstract

Prostate cancer (PCa) disproportionately affects men of African descent, with Nigeria recording high mortality rates, yet genetic studies in this population remain sparse. This study investigated the association between COMT rs4680 Val158Met, rs9332377, and CYP1B1 rs1056836 genetic variants and PCa risk and severity in Nigerian men. This case-control study involved 65 histologically confirmed PCa patients aged (median) 65 years old and 59 healthy controls aged (median) 60 years old. Genomic DNA was extracted from whole blood. Genotyping was conducted via TaqMan real-time PCR. Chi-square tests were conducted to compare genotype/allele frequencies, and associations were estimated using unadjusted logistic regression odds ratios (ORs) with 95% confidence intervals. Kruskal-Wallis tests and Spearman correlations were used to examine correlations with Gleason scores. Findings showed that there is a significant genotype and allele difference in COMT rs4680, where low-activity AA is the genotype that presents high risk (OR=9.50, 95% CI: 3.08-36.42, p<0.001 vs. GG), under genotypic as well as dominant models. In the case of rs9332377, the effect of the TT genotype showed a trend towards a protective effect but did not reach statistical significance (OR=0.21, 95% CI: 0.03-0.94, p=0.062 vs. CC). There were significant differences in CYP1B1 rs1056836, with the C alleles higher in cases (83.7% vs. 13.6%), and the GG risk being borderline (OR=4.074, p=0.056). None of the variants were significantly correlated with Gleason scores (p>0.05), although there was a trend in the case of rs1056836 (Spearman rho=0.263, p=0.089). These results suggest that genetic variation in COMT and CYP1B1 may contribute to PCa susceptibility among Nigerian men, potentially through impaired oestrogen detoxification pathways. Further validation in larger cohorts, with adjustments for environmental factors and comparisons across populations, is needed to clarify these associations.