Significance of Mitochondrial DNA Haplogroup on Epidermal Growth Factor Receptor Mutation in Japanese Patients With Lung Adenocarcinoma

Background/Aim: The frequency of somatic mutations of epidermal growth factor receptor (EGFR) in primary lung adenocarcinoma varies among populations and countries. The aim of the present study was to clarify whether the frequency of EGFR mutations in patients with lung adenocarcinoma depends on their mitochondrial DNA haplogroup, which reflects their maternal lineage. Patients and Methods: Using normal lung tissue specimens, the mitochondrial DNA haplogroup was determined by multiplex polymerase chain reaction in 135 Japanese patients who underwent surgery for primary lung adenocarcinoma. Results: The 135 patients were divided into two groups according to the two primitive haplotypes (N group, n=32; M group, n=103). The frequency of EGFR mutations in the N group was significantly higher than that in the M group (69% vs. 48%, p=0.044). The difference was prominent when the analysis was restricted to non-smokers (95% vs. 57%, p<0.01). Conclusion: The frequency of EGFR mutations in lung adenocarcinoma patients depends on their mitochondrial lineage.