Association between the catechol O-methyltransferase Val108/158Met polymorphism and alexithymia

It has been suggested that the characteristics of alexithymia result from deficits in frontal lobe functioning, and the prefrontal cortex is particularly dependent on the catechol O-methyltransferase (COMT) pathway. We investigated the relationship between COMT Val108/158Met, serotonin transporter coding sequence (5-HT transporter gene-linked polymorphic region; 5-HTTLPR) polymorphisms, and alexithymia. The study sample comprised 109 students at the Korea University. All participants were tested using the 20-item Toronto Alexithymia Scale (TAS-20). They were genotyped for COMT Val108/158Met and 5-HTTLPR polymorphisms. Genotyping was analyzed using polymerase chain reaction. Subjects with Val/Val genotype had significantly higher TAS-20 scores than those with Met/Met or Met/Val genotypes. However, there was no significant relationship between the 5-HTTLPR genotype and TAS-20 scores. This indicates a possible association between the COMT Val108/158Met gene polymorphism and alexithymia.