Identification of polymorphisms in mitochondrial cytochrome c oxidase genes as risk factors for gastric cancer

Although the incidence of gastric cancer (GC) has declined substantially in the past few decades, it remains the fifth most common cancer and the third most frequent cause of cancer deaths worldwide (1,2). GC is multifactorial, and it is very important to develop reliable biomarkers for predicting the risk of GC to maximize therapeutic effects and to minimize adverse effects of treatment. Many studies have evaluated the roles of nuclear DNA alterations in gastric tumorigenesis; however, relatively less attention has been paid to mitochondrial DNA (mtDNA) alterations (3)