Association analysis of genes in serotonin pathway with attention and executive function in patients with bipolar affective disorder

Background: The reason why it is difficult to identify susceptibility genes attributed to bipolar disorder (BPD) is the phenotypic heterogeneity. The use of endophenotypes has been advocated as one possible strategy to discovery cause variants of BPD. Methods: A total of 164 patients with BPD and 164 matched controls were employed in the present research. Fifty-two single nucleotide polymorphisms (SNPs) within the genes in serotonin pathway were selected for genotyping using the GoldenGate genotyping assay. All participants completed three neurocognitive tests including the tower of Hanoi (TOH), the Wisconsin card sorting test (WCST) and Trail making tests (TMTA and TMTB-M). Results: Patients with BPD demonstrated a wide range of deficits in mental activities of attention and speed of information processing, and executive function. Significant interactions between rs2760347 in 5HTR2A gene and diagnosis were found for the executive time of TOH, with beta = 11.82 and P = 0.002 (adjusted P = 0.03 after Bonferroni correction). Conclusions: Cognitive impairments existing in BPD may be particularly notable in certain domains of attention and executive function, and 5HTR2A gene may be involved in modulating executive function of BP-I patients. (C) 2014 Elsevier Inc. All rights reserved.