Interaction effects between COMT and BDNF polymorphisms on boredom susceptibility of sensation seeking traits

Sensation seeking is a temperament associated with willingness to take risks to obtain arousal. We investigated the relationship between the polymorphisms of the COMT Val158Met and BDNF Val66Met and sensation seeking traits. The Sensation Seeking Scale (SSS) and genotyping were performed in 277 Korean healthy volunteers (165 males, 112 females). Multivariate analysis of covariance was used to test the association between the COMT and BDNF functional polymorphisms and dimensions of sensation seeking, namely, disinhibition, boredom susceptibility, experience seeking and thrill/adventure seeking. No main and interaction effects of the COMT and BDNF on SSS were observed for total subjects. However, in females, a significant gene–gene interaction effect on the boredom susceptibility of SSS was shown. Among females with COMT Met present genotype (Val/Met + Met/Met), subjects with BDNF Met absent genotype (Val/Val) had significantly higher boredom susceptibility than subjects with BDNF Met. The effects of BDNF Val66Met polymorphism on boredom susceptibility of sensation seeking traits could be modulated by COMT Val158Met polymorphism in female.