FGFR2 is associated with bipolar disorder: A large-scale case-control study of three psychiatric disorders in the Chinese Han population

Objectives. Repetitive linkage analyses have indicated 10q25-q26 as a shared risk region for schizophrenia (SCZ) and bipolar disorder (BPD). A genome-wide association study and follow-up recently identified a significant association between a single nucleotide polymorphism (SNP) of this region (rs17101921) and SCZ. The nearest gene to this SNP is fibroblast growth factor receptor 2 (FGFR2). Methods. We carried out a large scale case-control study to test the association between FGFR2 and three major psychiatric disorders: SCZ, BPD and major depressive disorder (MDD) in the Chinese Han population. Eight tag SNPs were genotyped using Taqman assay in 1139 BPD patients, 1112 SCZ patients, 1119 MDD patients and 1135 shared healthy controls. Results. After correcting the multiple tests by permutation, one SNP (rs11199993), and a haplotype including this SNP, was found to be significantly associated with BPD. Potential population stratification in our samples was analyzed using 70 additional random SNPs dispersed on different chromosomes. No population stratification was detected, so our results could not be affected by this cofounding factor. Limitations of our study include incomplete coverage and insufficient power to detect association for relatively small odds ratio. Conclusions. Association between FGFR2 and BPD is worthy of further confirmation.