Subhaplogroup D4b1 enhances the risk of cervical cancer initiation: A case-control study in southern China.

Aim To investigate whether mitochondrial DNA (mtDNA) background (haplogroup) is associated with cervical cancer in patients in southern China. Methods A case-control study of 150 patients with cervical cancer and 217 geographically matched controls was conducted in Wenzhou, a southern Chinese city in the Zhejiang province. DNA from peripheral blood was extracted and sequenced. Sequences were aligned to the mtDNA revised Cambridge Reference Sequence (GenBank number NC_012920) to determine mtDNA single nucleotide polymorphisms (SNPs) and haplogroups. Results We found that both M and N haplogroups and their diagnostic SNPs (A10398G and C10400T) are not associated with the risk of cervical cancer. However, individuals with haplogroup D4b1/D4b1*, an M subhaplogroup, exhibited an increased risk of cervical cancer (odds ratio [OR] = 1.034; 95% confidence interval [CI] 1.004, 1.066; P = 0.011/OR =1.027; 95% CI 1.001, 1.055; P = 0.027). Individuals with SNPs C10181T/A10136G (OR =1.034; 95% CI 1.004, 1.066; P = 0.011/OR =1.027; 95% CI 1.001, 1.055; P = 0.027) were more susceptible to cervical cancer than individuals without. Furthermore, we determined that mtDNA background is not associated with the progression of cervical cancer. Conclusions Our results indicate that mtDNA haplogroups play a role in cervical cancer initiation.