Dysbindin associated with selective serotonin reuptake inhibitor antidepressant efficacy

Antidepressant drug efficacy is partially under genetic control and a number of gene variants have been associated with antidepressants efficacy over the last few years. In the search for further genes influencing antidepressant response we focused on the dysbindin gene (dystrobrevin-binding-protein 1, DTNBP1).

One hundred and four Korean inpatients affected by major depressive disorder were treated with various antidepressants at standard therapeutic daily doses and rated with the 10-items Montgomery-Asberg Depression rating scale (MADRS) at baseline and discharge. Five DTNBP1 variants (rs3213207 A/G, rs1011313 C/T, rs2005976 G/A, rs760761 C/T and rs2619522 A/C) were analysed for all patients.

Rs2005976 was found to be significantly associated with final MADRS scores, with the rarest A allele associated with higher final scores (P=0.00055), rs760761 also showed a significant association (P=0.0058) and rs2619522 showed a positive trend (P=0.025). Markers were not significantly associated with Clinical Global Impression Scale scores. Five marker haplotypes were mildly associated with MADRS final scores but when considering the block composed of the three single nucleotide polymorphisms individually associated with response (rs2005976, rs760761 and rs2619522), results were more marked (P=0.0096), with the more frequent G-C-A haplotype associated with a positive outcome.

Despite limitations due to the sample size and the mild antidepressant response, we observed a significant association between DTNBP1 variants and antidepressant response.