Vitamin D receptor polymorphisms and prostate cancer

Area of Science:

• Genetics
• Oncology
• Molecular Biology

Background:

• Prostate cancer risk factors are not fully understood, with low vitamin D levels implicated.
• Vitamin D receptor (VDR) gene polymorphisms, specifically TaqI and poly(A), have been previously linked to prostate cancer.
• VDR plays a role in the antineoplastic effects of 1,25-dihydroxy vitamin D (1,25-D).

Purpose of the Study:

• To investigate the association between VDR polymorphisms (TaqI and poly(A)) and prostate cancer risk.
• To examine if these VDR polymorphisms are associated with more advanced prostate cancer.
• To assess linkage disequilibrium between TaqI and poly(A) VDR polymorphisms.

Main Methods:

• A case-control study was conducted in North Carolina.
• DNA was extracted from peripheral blood of 77 prostate cancer cases and 183 controls.
• Polymerase chain reaction (PCR) techniques were used to genotype TaqI and poly(A) VDR alleles.

Main Results:

• No statistically significant association was found between TaqI or poly(A) VDR genotypes and prostate cancer risk (OR=1.4 and OR=1.2, respectively).
• No significant association was observed between these polymorphisms and advanced prostate cancer.
• Strong evidence of linkage disequilibrium between TaqI and poly(A) polymorphisms was detected (P < 0.0001), stronger in white participants.

Conclusions:

• The studied VDR polymorphisms (TaqI and poly(A)) do not appear to be significant risk factors for prostate cancer.
• These polymorphisms are not associated with disease progression in the studied population.
• Linkage disequilibrium exists between TaqI and poly(A) VDR polymorphisms, with ethnic variations noted.