Association of existing and new candidate genes for anxiety, depression and personality traits in older people.

Genetic variants that have previously been associated with personality traits and/or psychological distress, or inflammatory marker levels were investigated for their relationship to self-rated personality traits, anxiety, and depression in two elderly Scottish cohorts. Ten genes (29 SNPs) were investigated in the Lothian Birth Cohort 1936 (approximately 70 years, N = 1,091). Four of these genes and seven others (35 SNPs) were tested in the Lothian Birth Cohort 1921 who were measured on the same traits and states on two occasions (approximately 80 years, N = 550; 87 years, N = 229). For previously investigated candidate genes, some support (at a nominal significance level of 0.05/0.01) was found for association between NOS1 and personality traits (especially extraversion), PSEN1 and depression/neuroticism, and GRIK3 and depression. Of the inflammatory marker candidate genes, TF showed some association with psychological distress. No SNPs withstood the correction to significance level for multiple testing. Nevertheless, the results will be of importance to future meta-analyses of these candidate genes in relation to psychological distress and personality.