Vitamin D receptor genotypes are not associated with clinical response to calcipotriol in Korean psoriasis patients

Abstract.

Conflicting results have been reported on the association between BsmI restriction fragment length polymorphism (RFLP) at the vitamin D receptor gene (VDR) locus and the clinical response of psoriasis patients to calcitriol or calcipotriol therapy. We evaluated RFLPs of the VDR gene by analyzing the restriction pattern of polymerase chain reaction products in 55 Korean psoriasis patients receiving topical calcipotriol therapy, and evaluated the clinical response. Of the 55 patients, 43 completed the 8-week treatment protocol, and the response was evaluated as excellent in 9 patients, good in 20, and poor in 14. Thus, in our 43 patients BsmI and ApaI polymorphism in the VDR gene did not correlate with response to calcipotriol. The marked predominance of the b allele in the Korean population precludes the possibility that BsmI polymorphism is associated with clinical response to calcipotriol. The pattern of prevalence of the VDR genotypes in the Korean population is very different from that in Western populations. There were no differences in VDR genotype between controls and psoriasis patients at the BsmI site, but there were significant difference in terms of ApaI RFLP as previously reported. In conclusion, polymorphism analysis of the VDR gene with BsmI and ApaI restriction enzymes in psoriasis patients was not helpful in predicting clinical response to calcipotriol.