Case-control association study of 14 variants of CREB1, CREBBP and CREM on diagnosis and treatment outcome in major depressive disorder and bipolar disorder

Some evidence suggests an association between genetic variants within the cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB), CREB binding protein (CREBBP) and cAMP response element-modulator (CREM) and several psychiatric disorders. The present study investigated whether some single nucleotide polymorphisms (SNPs) within these genes could be associated with major depressive disorder (MDD) and bipolar disorder (BD) and whether they could predict clinical outcomes in Korean in-patients treated with antidepressants and mood stabilizers, respectively. The sample comprised 145 patients with MDD, 132 patients with BD and 170 psychiatrically healthy controls. Participants were genotyped for 14 SNPs within CREB1, CREBBP and CREM. Baseline and final clinical measures, including the Montgomery-Åsberg Depression Rating Scale and Young Mania Rating Scale for patients with MDD and BD, respectively, were recorded. All p-values were 2-tailed, and statistical significance was conservatively set at the 0.006 level in order to reduce the likelihood of false positive results. We failed to observe any association of the 14 SNPs genotypes or alleles with clinical improvement, response and remission rates as well as final outcomes in any of such disorders. Our findings suggest that the 14 SNP under investigation in our study do not influence diagnosis and treatment response in patients with MDD and BD. However, taking into account the several limitations of our study, further research is needed to draw more definitive conclusions.