Background Bach2 was reported to play a key role in T lymphocyte development and maturation to mediate immunological homeostasis. Several autoimmune and immune-related diseases were shown to be associated with Bach2 gene polymorphisms. The current study was designed to explore the association between Bach2 gene polymorphism with Vogt–Koyanagi–Harada (VKH) syndrome and Behcet's disease (BD) in a Chinese Han population.

Methods –427 patients with BD, 422 patients with VKH and 623 controls were recruited for the first stage from a Chinese Han population. The second stage included another set of 388 patients with BD and 460 healthy subjects. PCR fragment length polymorphism methodology was used for genotyping. Frequencies of genotypes and alleles were measured by direct counting and compared between cases and controls by χ² test.

Results No difference could be detected between patients suffering from BD or VKH with healthy controls concerning allele and genotype frequencies of rs11755527, rs3757247, rs12212193 and rs2474619. Although in the first stage the frequencies of genotype CC and AC of rs2474619 showed a weak statistical difference between BD and the control group (Pc=0.02), the difference was lost after the second stage and combined stage experiment.

Conclusions The investigated Bach2 gene polymorphisms (rs11755527, rs3757247, rs12212193 and rs2474619) are not related to the susceptibility to either VKH or BD in our investigated Chinese Han population.

Clinical trial registry This project was registered in the Chinese Clinical Trial Registry (registration number: ChiCTR-CCC-12002184).