Sex moderates the association between the COMT Val158Met single-nucleotide polymorphism and disorderliness facet of novelty seeking

Previous studies have shown inconsistent results regarding the effect of the Val158Met polymorphism of the catechol-O-methyltransferase (COMT) gene on personality and cognition. Here, nonclinical Caucasian university students of Italian origin were administered the Temperament and Character Inventory-Revised, Tellegen Absorption Scale, Differential Attentional Processes Inventory, and Waterloo-Stanford Group Scale of Hypnotic Susceptibility. We found that the COMT Val158Met polymorphism was significantly associated with the disorderliness facet of novelty seeking (NS4) and that sex was a moderator of this association. Females with the Met/Met genotype showed higher NS4 scores compared to those with the Val/Met and Val/Val genotypes. No significant genotype effect was found for males. Additionally, we failed to find a significant effect of the COMT gene on attention and hypnotic suggestibility measures. These results provide further evidence for a sex-specific influence on the gene-behaviour associations. Polymorphisms in dopamine system genes are reported to play a crucial role in influencing various aspects of plays a crucial role in influencing various aspects of personality traits and cognitive performance; however, previous studies have shown inconsistent results on the involvment of the functional Val158Met polymorphism of the catechol-O-methyltransferase (COMT) gene. In the present study, nonclinical Caucasian university students of Italian origin were administered the Temperament and Character Inventory-Revised, Tellegen Absorption Scale, Differential Attentional Processes Inventory, and Waterloo-Stanford Group Scale of Hypnotic Susceptibility. We found that the COMT Val158Met polymorphism was significantly associated with the disorderliness facet of novelty seeking (NS4) and that sex was a moderator of this association. Females with the Met/Met genotype showed higher NS4 scores compared to those with the Val/Met and Val/Val genotypes. In contrast, no significant genotype effect was found for males. Additionally, we failed to find a significant association of COMT enzyme activity with attention and hypnotic suggestibility measures. These results provide further evidence of a sex-specific influence on the gene-behaviour association.