Background: Disgust is a basic emotion that involves feelings of revulsion and withdrawal behavior from dangerous/infectious situations. Very little is known about the genetic basis of disgust sensitivity. The dopamine receptor D4 (DRD4) and catechol-O-methyltransferase (COMT) genes have been implicated in neuroticism-related traits and approach-related temperaments which are supposed to be associated with disgust sensitivity. The present study aimed to investigate the possible relationship between disgust sensitivity and COMT Val158Met and DRD4 variable number of tandem repeats (VNTR) polymorphisms in healthy subjects.
Methods: In total, 241 healthy Korean college students were recruited, and the 228 participants with a complete data set (127 males and 101 females) were included in the data analysis. Disgust sensitivity was assessed using the Disgust Scale-Revised (DS-R) and genotyping of COMT Val158Met and DRD4 VNTR polymorphisms was performed.
Results: The Val/Val groups of COMT had significantly higher scores than the non-Val/Val group for the Animal-Reminder and the Contamination-Based Disgust scores as well as for total DS-R scores. Additionally, the non-2-repeat allele group of DRD4 had a tendency to a significantly higher disgust sensitivity than the 2-repeat allele group for Contamination-Based Disgust.
Conclusions: These findings suggest that disgust sensitivity may be affected by genetic components, such as dopamine-related genes.