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.