ABSTRACT
BACKGROUND: The purpose of this study was to determine whether the distribution of vitamin D receptor (VDR) polymorphisms in rheumatoid arthritis (RA) patients group is different from that of the control group and whether there is a relationship between VDR genotype and radiographic severity or bone mineral density (BMD) of RA patients. METHODS: The VDR genotype was determined by polymerase chain reaction and digestion with three restriction enzymes Taq I, Apa I and Bsm I in 78 healthy women and 97 female RA patients. Hand X-rays were scored by Larsen's method and bone mineral density was measured by dual energy X-ray absorptiometry (DEXA) in RA patients. RESULTS: VDR genotypic distributions in Koreans were much different from Caucasians in each control and RA patient groups. Especially, "tt" allele and "BB" allele were very rare, prominently differentiating from Caucasians. But within Koreans, no significant difference of VDR genotypic frequency was observed between control group and RA patients group. And there was no significant relationship of VDR genotype with radiographic scores, nor with BMD scores in RA patients. CONCLUSION: The distribution of VDR polymorphisms in Korean RA patients was not different from controls. The VDR polymorphisms correlate neither with the radiographic severity of RA, nor with BMD scores in Korean RA patients.