Vitamin D Receptor Gene BsaM I Polymorphism as Genetic Marker in Patients with Calcium Stone

Seo, Ill Young; Park, Keung Won; Park, Seung Chol; Lee, Soun Jung; Kim, Min Su; Kim, Jeong Joong; Rim, Joung Sik

Abstract

PURPOSE: To identify candidate genes related with urolithiasis, the vitamin D receptor (VDR) gene polymorphisms were searched.
MATERIALS AND METHODS
Between July 2002 and June 2003, 212 healthy subjects, used as normal controls, and 155 patients with urolithiasis were examined. The control volunteers had no histories of urolithiasis, familial stone disease or osteoporosis. The patients underwent a stone metabolic study and stone analysis. 49 patients received a stone analysis, of which, 45 had calcium stones. Using a polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) analysis of peripheral blood, the association between the VDR gene BsaM I polymorphism and urolithiasis was evaluated. The polymorphism was divided into three groups: excisable (C/C), unexcisable (T/T) and heterozygote (C/T).
RESULTS
For the VDR gene BsaM I polymorphism, there was no statistically difference between the control and the urolithiasis groups. The distribution of VDR genotypes in the 155 patients with urolithiasis was as follows: C/C, 139 (89.7%); C/T, 12 (7.7%) and T/T, 4 (2.6%), which was not significantly different from that in the 212 control subjects: C/C, 195 (92.0%); C/T, 14 (6.6%) and T/T, 3 (1.4%). The frequencies of VDR genotypes in the 45 patients with calcium stone were: C/T (13.3%) and T/T (6.7%), and that of the T allele 13.3%, which were significantly different from those of the controls: C/T (6.6%) and T/T (1.4%) and that of the T allele, 4.7% (p<0.05).
CONCLUSIONS
VDR BsaM I polymorphism appears to be a good candidate for a genetic marker in calcium stone disease. The T allele especially may be in charge of the pathogenesis of calcium stones. Further analysis and case accumulation are required to identify the genetic marker of urolithiasis. (Korean J Urol 2004;45:1143-1147)