Association between the Catechol-O-Methyltransferase (COMT) Val¹⁵⁸Met Polymorphism and Alexithymia in Patients with Obsessive-Compulsive Disorder

• Published in: Yonsei medical journal Vol. 57; no. 3; pp. 721 - 727
• Main Authors: Koh, Min Jung, Kang, Jee In, Namkoong, Kee, Lee, Su Young, Kim, Se Joo
• Format: Journal Article
• Language: English
• Published: Korea (South) Yonsei University College of Medicine 01.05.2016; 연세대학교의과대학
• Subjects: Adult; Affective Symptoms - diagnosis; Affective Symptoms - genetics; Affective Symptoms - psychology; Alleles; Catechol O-Methyltransferase - genetics; Female; Genotype; Humans; Male; Middle Aged; Obsessive-Compulsive Disorder - diagnosis; Obsessive-Compulsive Disorder - genetics; Obsessive-Compulsive Disorder - psychology; Original; Phenotype; Polymorphism, Genetic; Republic of Korea; 의학일반; Toronto alexithymia scale; endophenotype; obsessive-compulsive disorder; Alexithymia; COMT Val¹⁵⁸Met polymorphism
• ISSN: 0513-5796; 1976-2437; 1976-2437
• DOI: 10.3349/ymj.2016.57.3.721

Alexithymia, defined as a deficit in the ability to recognize and describe one's own feelings, may be related to the development and maintenance of obsessive-compulsive symptoms. The aim of this study was to evaluate the association between the catechol-O-methyltransferase (COMT) Val¹⁵⁸Met polymorphism and alexithymia in patients with obsessive-compulsive disorder (OCD). We recruited 244 patients with OCD (169 males, 75 females). Alexithymia was assessed using the 20-item Toronto Alexithymia Scale (TAS-20), and genotyping of the COMT Val¹⁵⁸Met polymorphism was evaluated. Patients with the COMT Val/Val genotype had significantly higher total and "difficulty identifying feelings" (DIF) subdimension scores than those with the Val/Met or Met/Met genotypes. Patients with the COMT Val/Val genotype had significantly higher "difficulty describing feelings" (DDF) subdimension scores than those with the COMT Val/Met genotype. However, there were no differences in the scores for the "externally oriented thinking" (EOT) subdimension among the three genotypes. These results indicate that the high-activity Val allele of the COMT Val¹⁵⁸Met polymorphism is associated with increased alexithymic traits in patients with OCD. The present finding suggests that alexithymia is an endophenotype of OCD that is mediated by the COMT Val¹⁵⁸Met polymorphism.