Background: Genome methylation may modulate synaptic plasticity, being a potential background for mental disorder. Adverse childhood experiences (ACEs), known to be frequently reported by patients with alcohol dependence (AD), have been proposed as one of environmental inequities influencing DNA methylation. The study is aiming 1.To assess a promoter region methylation in gene for somatostatin receptor subtype-4 (SSTR4), a receptor for somatostatin, a neurotransmitter engaged in neuroplasticity and memory formation, in patients with AD; 2. To verify if SSTR4 promoter methylation is associated with ACEs and other selected environmental factors. Methodology: 176 patients with AD and 127 healthy controls were interviewed regarding 13 categories of ACEs; a structured self-reported questionnaire - to measure the sociodemographic and clinical characteristics; a module of Catalogue of Healthy Behavior - to assess nutritional health habits; the Alcohol Use Disorders Identification Test - to assess drinking severity. The SSTR4 promoter region methylation status was performed via methylation-specific PCR, and the genotyping for the SSTR4 rs2567608 functional polymorphism - according to the manufacturer's standard PCR protocol.
Results: SSTR4 promoter region was found methylated in 21.6% patients with AD and 2.3% controls. None of following characteristics: current age, gender, term and kind of labor, 13 categories of childhood trauma, diet, alcohol drinking severity, age at alcohol drinking initiation, age at onset of problem drinking, cigarette smoking, and SSTR4 rs2567608 was a significant predictor for SSTR4 promoter region methylation.
Conclusions: SSTR4 promoter region methylation in here studied participants may be either inherited epigenetic modification or secondary, but not to here assessed variables.
Keywords: Adult Survivors of Child Adverse Events; Alcoholism; DNA Methylation; Memory; Somatostatin Receptor Subtype-4.