Sequence variants in the human 25-hydroxyvitamin D3 1-α-hydroxylase (CYP27B1) gene are not associated with prostate cancer risk

BACKGROUND. 1,25-dihydroxyvitamin D-3 has been shown to have antiproliferative properties on normal and neoplastic prostatic cells. 25-hydroxyvitamin D-3 1-alpha-hydroxylase, the enzyme that catalyzes the final step of vitamin D synthesis, converting 25-hydroxyvitamin D-3 to 1,25-dihydroxyvitamin D-3, is expressed in the prostate. METHODS. The human 25-hydroxyvitamin D-3 1-a-hydroxylase gene (CYP27B1) was resequenced in a case/control panel consisting of 64 individuals (48 Caucasians and 16 African Americans), with equal numbers of hereditary prostate cancer cases, sporadic cases, and unaffected controls. Three frequent single nucleotide polymorphisms (SNPs) were genotyped in 245 prostate cancer cases and 222 controls. RESULTS. Six noncoding SNPs were identified in the CYP27BI gene. No significant difference was found in allele and genotype frequencies between sporadic cases and unaffected controls for the three genotyped SNPs. CONCLUSION. This study suggests that the CYP27B1 gene does not play a major role as a prostate cancer susceptibility gene.