Personality is a determinant of behavior and lifestyle associated with health and human diseases. Although personality is known to be a heritable trait, its polygenic nature has made the identification of genetic variants elusive. We performed a genome-wide association study on 1089 Korean women aged 18-40 years whose personality traits were measured with the Revised NEO Personality Inventory for the five-factor model of personality. To reduce environmental factors that may influence personality traits, this study was restricted to young adult women. In the discovery phase, we identified variants of PTPRD (protein tyrosine phosphatase, receptor type D) that associated this gene with the Openness domain. Other genes that were previously reported to be associated with neurological phenotypes were also associated with personality traits. In particular, DRD1 and OR1A2 were linked to Neuroticism, NKAIN2 with Extraversion, HTR5A with Openness and DRD3 with Agreeableness. Data from our replication study of 2090 subjects confirmed the association between OR1A2 and Neuroticism. We first identified and confirmed a novel region on OR1A2 associated with Neuroticism [corrected]. Candidate genes for psychiatric disorders were also enriched. These findings contribute to our understanding of the genetic architecture of personality traits and provide critical clues to the neurobiological mechanisms that influence them.