Association of genetic polymorphisms with personality profile in individuals without psychiatric disorders

Population-based twin studies demonstrate that approximately 40-50% of the variability in personality dimensions results from genetic factors. This study assessed selected polymorphisms in the COMT Val158Met, MAOA 3'VNTR, 5HTTLPR, 102T/C 5-HT2A, DAT 3'VNTR and DRD2 exon 8 genes and evaluated their association with personality profiles, anxiety levels, and depressiveness in healthy subjects.

This study included 406 unrelated (mean age 38.51 years), mentally and somatically healthy Caucasian subjects of Polish origin. The prevalence of the gene variants mentioned above and their association with personality profiles, anxiety levels, and depressiveness was assessed using the Temperament and Character Inventory, NEO Five-Factor Inventory, Spielberger's State-Trait Anxiety Inventory and Beck's Depression Inventory.

The effects of the 5HTTLPR gene on the s/s genotype and empathy (C2) were lowest in the entire group. The effects of gender, age and the HT2A gene for the T/T genotype and attachment (RD3) were highest in women. The effects of gender, age and the DAT gene on the 9/9 DAT genotype, compassion (C4) and cooperativeness (C) were lowest in women. The effects of gender, age and the COMT gene on the Met/Met genotype and neuroticism (NEU) NEO-FFI were also lowest in women.

Our results suggest considerable influence of individual genes on the formation of personality traits.