Association between Vitamin D Receptor Gene Polymorphisms and Idiopathic Hypocitraturia in the Chinese Population

Introduction: Idiopathic hypocitraturia is a known risk factor for urolithiasis. Several studies have shown an association between vitamin D receptor (VDR) gene polymorphisms and urolithiasis. The aim of this study was to investigate the relationship between VDR gene polymorphisms and idiopathic hypocitraturia in a Chinese population. Subjects and Methods: We chose 50 Chinese subjects with normal urinary citrate levels (N) and 31 Chinese subjects with idiopathic hypocitraturia (L). The VDR polymorphisms BsmI, FokI, TaqI, and ApaI were detected using the PCR-RFLP technique, and the relationship between these polymorphisms and the presence of idiopathic hypocitraturia was analyzed. Results: We found that the prevalence of 'bb', 'ff', and 'TT' VDR genotypes were significantly higher in the 'L' group than in the 'N' group (p < 0.05). We also found much lower 24-hour urinary citrate concentrations in patients with 'bb', 'ff', and 'TT' genotypes than in patients with other genotypes (p < 0.05). Conclusions: These results showed that there might be a genetic association between BsmI, FokI, and TaqI VDR polymorphisms and idiopathic hypocitraturia in the Chinese population. Copyright (C) 2010 S. Karger AG, Basel