GWA meta-analysis of personality in Korean cohorts.

Personality is a determinant of behavior and lifestyle that is associated with health and human diseases. Despite the heritability of personality traits is well established, the understanding of the genetic contribution to personality trait variation is extremely limited. To identify genetic variants associated with each of the five dimensions of personality, we performed a genome-wide association (GWA) meta-analysis of three cohorts, followed by comparison of a family cohort. Personality traits were measured with the Revised NEO Personality Inventory for the five-factor model (FFM) of personality. We investigated the top five single-nucleotide polymorphisms (SNPs) for each trait, and revealed the most highly association with neuroticism and TACC2 (rs1010657, P=8.79 × 10(-7)), extraversion and PTPN12 (rs12537271, P=1.47 × 10(-7)), openness and IMPAD1 (rs16921695, P=5 × 10(-8)), agreeableness and RPS29 (rs8015351, P=1.27 × 10(-6)) and conscientiousness and LMO4 (rs912765, P=2.91 × 10(-6)). It had no SNP reached the GWA study threshold (P<5 × 10(-8)). When expanded the SNPs up to top 100, the correlation of PTPRD (rs1029089) and agreeableness was confirmed in Healthy Twin cohort with other 13 SNPs. This GWA meta-analysis on FFM personality traits is meaningful as it was the first on a non-Caucasian population targeted to FFM of personality traits.

Genome-wide association study of the five-factor model of personality in young Korean women.

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.

Association between blood lipid levels and personality traits in young Korean women.

Abnormal lipid levels are important etiological factors associated with the development of atherosclerosis and with increased cardiovascular morbidity and mortality. Lipid levels are also influenced by lifestyle and behavioral factors, which suggests that personality traits might be related to abnormal lipid profiles. Studies on personality traits and lipid levels are relatively scarce in Korea. Therefore, the objective of this study was to examine the association between lipid levels and personality traits in young Korean women. A total of 1,701 young Korean women [mean age  = 24.9±4.6 years (range 17-39)] who volunteered for personality trait evaluation were recruited for this study. Lipid levels, including total cholesterol, high density lipoprotein (HDL) cholesterol, and triglyceride, were measured in all subjects after an overnight fast, and a low density lipoprotein (LDL) cholesterol level was calculated. The study population was divided into abnormal and normal lipid level groups according to the clinical criteria. Personality traits were measured using the Revised NEO Personality Inventory for the Five-Factor Model of personality. High neuroticism was associated with low HDL cholesterol levels. Low extraversion and openness were associated with high levels of triglyceride. At the facet level, the association between personality and lipid levels were generally consistent. Angry hostility, self-consciousness, vulnerability to stress, activity, and straightforwardness were associated with HDL cholesterol levels. Activity, positive emotion, aesthetics, actions, and deliberation were associated with triglyceride. When applying clinical criteria, conscientiousness was less likely to have abnormal total cholesterol levels. Our results showed that the women with the low HDL cholesterol levels are like to be more neurotic and the hyperglycemic women are prone to lower extraversion and openness in Korea. Understanding the associations between blood lipid levels and personality traits may have a beneficial effect for the managing of dyslipidemia.

Personality traits and body mass index in a Korean population.

BACKGROUND: Overweight and obesity is a serious problem worldwide related to cardiovascular and other diseases. Personality traits are associated with the abnormal body mass indices (BMIs) indicative of overweight and obesity. However, the links between personality traits and BMI have been little studied in Korea. METHODS: We evaluated the association between personality traits and BMI in men and women using the rural Ansung and urban Ansan cohort from the Korean Genome Epidemiology Study, and the Kangbuk Samsung Hospital Cohort Study datasets. A shorter version of the original Revised Neuroticism-Extroversion-Openness Personality Inventory (NEO-PI-R) was used to measure the five-factor model of personality (neuroticism, extraversion, openness to experience, agreeableness, and conscientiousness). RESULTS: Data from a total of 1,495 men (mean age 60.0 ± 9.8 years; mean BMI 24.3 ± 3.0 kg/m2) and 2,547 women (mean age 47.0 ± 15.5 years; mean BMI 22.8 ± 3.4 kg/m2) were included in the analysis. Compared with the normal weight groups, overweight and obese men scored higher on openness to experience and lower on conscientiousness. Overweight and obese women scored lower on neuroticism and openness to experience and higher on agreeableness. Extraversion was positively associated with BMI in men (ß=0.032, P<0.05). BMI and waist circumference were significantly increased in individuals who were less dutiful. In women, neuroticism was inversely associated with BMI (ß=-0.026, P<0.05). Openness to experience was negatively, and agreeableness was positively, associated with BMI (openness to experience: ß=-0.072, agreeableness ß=0.068) and waist circumference (openness to experience: ß=-0.202, agreeableness: ß=0.227) (P<0.05). CONCLUSION: Personality traits were associated with underweight, overweight, and obesity in men and women. Increased understanding of the underlying factors contributing to this association will aid in the prevention and treatment of abnormal BMI.