Val1483Ile polymorphism in the fatty acid synthase gene was associated with depressive symptoms under the influence of psychological stress

Background: To study the association between lipid-metabolism and depressive symptoms, genetic polymorphisms in serotonin transporter linked promoter region (5-HTTLPR) and fatty acid synthase gene (FASN) were investigated. Method: A cross-sectional study was conducted on 177 women (n = 166) and men (n = 15) recruited from workers in a hospital and nursing homes in Japan. Depressive symptoms were assessed by the Center for Epidemiologic Studies Depression (CES-D) scale and perceived psychological stress was measured using visual analogue scale (VAS). The genotypes of 5-HTTLPR (insertion/deletion; L/S), and FASN (Val1483Ile) were determined by the PCR methods. Linear regression analysis was performed, in which CES-D scores served as a dependent variable, and VAS scores, gene polymorphism, and confounders as independent variables. Results: Under the influence of perceived stress, S/S carriers of the 5-HTTLPR gene showed significantly higher CES-D scores in comparison with L/L + L/S carriers (F = 8.2, standardised β = 0.15, p < 0.05). Regression analysis also confirmed that CES-D scores in participants with Ile/Ile + Val/Ile genotypes of the FASN gene were significantly higher than those with Val/Val genotype (F = 8.4, standardised β = 0.16, p < 0.05). In relation to physical features, BMI among participants with S/S genotype of 5-HTTLPR was significantly lower compared with those with L/L + L/S genotypes. Conclusions: The Val1483Ile polymorphism in the FASN was associated with depressive symptoms under the influence of psychological stress. The S variant of 5-HTTLPR was related with less obese.