Association of polymorphic marker Val158Met of COMT gene with depression in an open population 25–44 years old (WHO international program MONICA, epidemiological study)

Objective: to investigate the association of the polymorphic marker Val158Met in the catechol-O-methyl transferase (COMT) gene with depression in an open population aged 25–44 years.Patients and methods. A representative sample of the population living in Oktjabr'skij district of Novosibirsk aged 25– 44 years (427 men, median age – 34±0.4 years, response rate – 71%; 548 women, median age 35±0.4 years, response rate – 72%) was screened in 2013–2016 (budget framework № 0324- 2018-0001, Reg. № AAAA-A17-117112850280-2). In addition to the standard epidemiological examination, screening participants underwent psychological testing, which determined the level of depression. Study participants who underwent COMT Val158Met (rs4680) polymorphism genotyping were randomly assigned to a cohort of 224 men and 217 women. Pearson's χ2 test was used to test the statistical significance of differences between these groups; p≤0.05 was considered statistically significant in all types of analysis. Results and discussion. In an open population aged 25–44 years, the prevalence of severe depression (SD) was 13.2%, moderate depression – 24.4%. SD was more prevalent in COMT G/G genotype carriers (61.8%), compared to A/A genotype carriers (38.2%; χ2=6.097; df=2, p=0.047); the G allele carriers also had a higher prevalence of SD (55.3%), compared to A allele carries (44.7%; χ2=5.408; df=1; p=0.02). SD was less prevalent among male COMT A/A genotype carriers (15.8%), compared to G/A genotype carriers (84.2%; χ2=4.603; df=1; p=0.032). SD was more prevalent in female G/G genotype carriers (65.5%), compared to A/A genotype carriers (34.5%; χ2=4.769; df=1; p=0.029). The G allele was more common among women with SD (58.2%) than the A allele (41.8%; χ2=6.658; df=2; p=0.01). In a logistic regression model, COMT Val/Val genotype in the studied population [Relative risk (RR) 1.594], as well as G (Val) allele in the studied population (RR=1.378) and women (RR=1.557), significantly increased the risk of depression. Conclusion. The data allows us to assume that COMT G/G polymorphism may be linked to a high depression level.