Single nucleotide polymorphisms in the mitochondrial displacement loop and age at onset of epithelial ovarian cancer
Abstract Objective: The accumulation of the single nucleotide polymorphisms (SNPs) in the mitochondrial displacement loop (D loop) has been reported in many types of cancers. And the association with the risk and prognosis of cancers also has been described extensively. In the present study, we investigated the association between the age at onset and SNPs in the D loop of mitochondria DNA (mtDNA) using a population based series of primary epithelial ovarian cancer (EOC) patients. Methods: The D loop region of mtDNA samples from blood were obtained from 89 patients with primary EOC, who underwent surgery. The age at onset curves were calculated by Kaplan Meier method and compared by the log rank test. Results: The SNP sites of nucleotide 248, 524 and 16,304 alleles were identified for their association with age at onset by the log rank test. The age at onset of patients with the minor allele 248 G was lower than that of patients with 248 A. The same was seen for the rare allele 16,304 T genotype when compared with matched allele 16,304 C at the 16,304 site. But the age at onset of patients with the minor allele 524 C was higher than that of patients with frequent 524 deletions. Conclusion: Genetic polymorphisms in the D loop are the predictive markers for age at onset in EOC patients. Accordingly, the analysis of genetic polymorphisms may help identify EOC patient subgroups at high risk of early onset.
Mitochondrial DNA. Part A, DNA mapping, sequencing, and analysis