The VDR and TNF-? Gene Polymorphisms in Iranian Tuberculosis Patients: The Study on Host Susceptibility

Abstract

Background: VitaminD receptor (VDR) and tumor necrosis factoralpha (TNF-?) genes are thought to be important in the intracellular killing of mycobacteria. This study aimed to determine the association of VDR and TNF-? variant with development of pulmonary tuberculosis (PTB) among Iranian patients. Patients and methods: Selected regions of VDR and TNF-? were amplified, and then the PCR products were digested using restriction enzyme (RFLP). Digested products were run on 8% polyacrylamide gel, and were stained with silver nitrate. Single nucleotide polymorphisms (SNPs) at restriction sites of BsmI, and FokI of VDR gene and SNPs of TNF-? at -238,-308, -244,-857,-863 positions were analyzed by PCR-RFLP among 117 PTB cases and 60 healthy controls. Results: No statistically significant difference was observed in allele frequencies of FokI of VDR and TNF-? at -238, -244,-863 and 857 position. Although, the frequency of b allele of BsmI (p=0.001) and -308 A variant in TNF-? promoter region (p=0.006) were significantly more in PTB patients than healthy controls. The frequency of extended diplotypes were different in patients and control subjects (p Conclusion: This study confirmed the association of VDR BsmI and TNF-? -308A with susceptibility to tuberculosis in Iranian PTB patients. In addition, the results showed the importance of haplotypes and diplotypes analysis in determining the host susceptibility against TB