Gene–gene interaction analysis of personality traits in a Japanese population using an electrochemical DNA array chip analysis

It has been suggested that genes involved in the central dopaminergic pathway may contribute to personality traits. However, the results of association studies for these genes have not been consistent. The present study investigated the relationship between the specific polymorphisms of MAO-A, COMT, DRD2, DRD3 and personality traits in Japanese women using a novel genotyping method involving electrochemical DNA array (ECA) chip analysis. Single marker association analysis for each mutation revealed no significant association between scores for Neuroticism Extraversion Openness-Five Factor Inventory (NEO-FFI) items. Gene–gene interaction analysis showed that a MAO-A 30-bp repeat × COMT (Val158Met) × DRD3 (Ser9Gly) had a marginally significant association with Agreeableness (P = 0.0547). The present results suggest that a combination of polymorphisms of MAO-A, COMT, and DRD3 might affect personality traits in Japanese women.