VDR and VDBP genes polymorphisms associated with susceptibility to tuberculosis in a Han Taiwanese population.

BACKGROUND: The active metabolite (1, 25-dihydroxycholecalciferol) of vitamin D (25-hydroxycholecalciferol) leads to the activation of macrophages and the deficiency of vitamin D seems to be involved in the risk of tuberculosis (TB). The effects of vitamin D are exerted by interaction with the vitamin D receptor (VDR) and vitamin D receptor binding protein (VDBP) may be influenced by polymorphisms in the VDR and VDBP genes. In this study, variation in the VDR and VDBP genes was investigated in a Taiwanese population with TB.

METHODS: We typed four VDR polymorphisms of restriction endonuclease sites for ApaI, TaqI, BsmI, and FokI and three VDBP polymorphisms-Thr420Lys, Asp416Glu, and Cys299Cys-in 198 patients with TB and 170 healthy volunteers.

RESULTS: VDR TaqI, VDR BsmI, and VDBP Asp416Glu were significantly associated with TB susceptibility. Odd ratios of risk genotypes of the above three polymorphisms were 2.16 (95% confidence interval 1.01, 4.65), 2.14 (95% confidence interval 1.06, 4.31), and 2.24 (95% confidence interval 1.04, 4.80), respectively. VDBP haplotype analysis showed Gc1f carriers associated to TB.

CONCLUSION: The polymorphisms in the VDR and VDBP genes appeared to be responsible for host susceptibility to human TB in a Taiwanese population.