Association between single nucleotide polymorphism of vitamin D receptor start codon Fok I and urinary calcium level

Objective To investigate the association between single nucleotide polymorphism (SNP) of Fok Ⅰ [the vitamin D receptor (VDR) start codon] and urinary calcium level. Methods Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to determine the Fok Ⅰ ploymorphism in peripheral blood samples from SO patients with (urinary stone group) and another 50 without urinary stones (control group). The genotype distribution and frequencies of Fok Ⅰ allele were compared between two groups. 24-h urinary calcium level was measured by routine urinalysis. Results The distribution of genotypes (urinary stone group vs controls) was 28% (14/50) vs 34% (17/50) for FF, 52% (26/50) vs 56% (28/50) for Ff, 20% (10/50) vs 10% (5/50) for ff, with the statistical differencs for FF and ff between two groups (P 0.05) , and 46% (46/100) in urinary stone group vs 38% (38/100) in the controls, respectively (P 0.05) of two groups. Conclusions The polymorphism of VDR start codon Fok I may be associared with increase of urinary calcium level in patients with urinary stones. Key words: Urinary calculi; Receptors, calcitriol; Polymorphism, single nucleotide; Codon, initiator ; Urinary calcium