Relationship Between the P16 Gene Exon 3 C/G Polymorphism and Hydropyruvate Reductase (GRHPR) Gene Exon 6 G/A Polymorphism in Patients With Calcium Oxalate Stone：No Association

Background. Serial reports have shown a correlation between genetic polymorphisms and stone disease. Because the p16 protein is related to cell death, it is presumed to be associated with the function of renal cell death in response to oxalate overload. Hydroxypyruvate reductase (HPR) and glyoxylate reducatse (GR) (GRHPR) are enzymes involved in oxalate metabolism and are related to a congenital disorder of calcium oxalate stone formation. We therefore investigated the role these genes play in the formation of calcium oxalate stone disease. Methods. A normal control group made up of 101 healthy people and 143 patients with recurrent calcium oxalate stone were examined in this study. The polymorphism was detected following the results of polymerase chain reaction based restriction analysis of Msp I ("C" allele is excisable) in the p16 gene (exon 3 C/G polymorphism). An exon 6 C/G polymorphism of the GRHPR gene was identified by Bgl II endonuclease ("G" allele is excisable). Results. In the p16 gene Msp I polymorphism, the frequency of the C/G heterozygotes was 2.8% in the stone group and 5.9% in the control group. The frequency of the G/G allele was 97.2% and 99.1% in the stone and control groups respectively (p = 0.326, chi-square test). In the GRHPR gene Bgl II polymorphism, the frequency of the GG allele was over 98% in both groups (p = 1.0, Fisher's exact test). The frequency of GA heterozygotes was 2.0% in the control group and 1.4% in stone patients. The distribution showed no statistical difference between hypercalciuric and normocalciuric patients. Conclusions. Neither the p16 gene Msp I G/C polymorphism nor the GRHPR Bgl II G/A polymorphism is associated with stone disease. ( Mid Taiwan J Med 2002;7:94-100)