Abstract: Objective: To investigate the relationship between single nucleotide polymorphisms in mitochondrial displacement-loop and the risk of renal cell carcinoma. Methods: We selected 59 clear cell renal cell cancer patients who received nephrectomy in the Department of urinary surgery at the Fourth Hospital of Hebei University between 2002 and 2007. We also collected 68 healthy female controls. Total DNA was extracted using a Wizard Genomic DNA extraction kit (Promega, Madison, WI, USA) and stored at -20℃. PCR was performed according to the protocol of PCR Master Mix Kit (Promega) and purified prior to sequencing. Cycle sequencing was performed with the Dye Terminator Cycle Sequencing Ready Reaction Kit (Applied Biosystem, Foster City, CA, USA) and the products were then separated on the ABIPRISM Genetic Analyzer 3100 (Applied Biosystem). Polymorphisms were confirmed by repeated analyses from both strands. Results: SNPs were detected in 143 sites of the 982-bp mitochondria D-Loop region from blood samples of the ccRCC patients and the healthy controls. No statistical reference exist for distribution frequency of each SNP referring to age and sex. A statistically significant increase in SNP frequency for the 16293G, 262T alleles was observed in clear cell renal cancer patients (p<0.05), whereas the SNP frequency for the 16298C, 319A alleles was decreased in clear cell renal cell cancer patients. Conclusion: analysis of genetic polymorphisms in the D-loop may help to identify patient subgroups at a higher risk for developing RCC, thereby helping to refine therapeutic decisions for these patients.

Key words: D-loop, clear cell renal cell carcinoma, SNP, mtDNA