P-699 - Selective DNA methylation of BDNF promoter in bipolar disorder: differences among patients vs controls and potential influence of pharmacological treatments

Introduction The etiology of bipolar disorder (BD) is poorly understood, involving genetic, epigenetic mechanisms and environmental contributions. Aim Among the candidate genes associated with major psychoses, the present study investigated the degree of DNA methylation at brain-derived neurotrophic factor (BDNF) gene promoter in peripheral blood mononuclear cells (PBMCs) isolated from bipolar patients. Methods DNA was isolated from the blood of 94 BD patients (49 BD I and 45 BD II) and 52 controls and converted with sodium bisulfite. Real Time Methylation Specific PCR was performed to quantify promoter methylation. Results A significant BDNF gene expression down-regulation was observed in BD II 0.53 ± 0.11%; p  Conclusions Present findings suggest selective changes in DNA methylation of BDNF promoter in subjects with BD type II and highlight the importance of epigenetic factors in mediating the patophysiology an treatment response of BD.