Genetic association between BDNF gene polymorphisms and phobic disorders: A case–control study among mainland Han Chinese

Phobic disorders are a common group of syndromes comprising persistently recurring, irrational severe anxiety of specific objects, activities, or situations with avoidance behavior of the phobic stimulus. The present study investigated the association between whole region polymorphisms, (including the Val66Met variant), in the BDNF gene and phobic disorders among Han Chinese young adults. We conducted a case–control study to investigate the genetic association between BDNF polymorphisms and phobic disorders among mainland Chinese. One hundred and twenty young adults with phobic disorders and 267 matched controls were recruited. Three tag SNPs of BDNF were successfully genotyped by using PCR-based ligase detection reaction (PCR-LDR). We found significant differences in allele distributions of SNP rs10835210 (P < 0.001) between the experimental and the control groups. In the haplotype analysis based on linkage-disequilibrium across this gene locus, we demonstrated significant association between phobic disorders and BDNF haplotype CAC (P = 0.004). Association was significant after 104 permutation tests (P < 0.001). To the best of our knowledge, this is the first study showing that the BDNF gene may play a significant role in the etiology of phobic disorders in the Han Chinese population.