Objective: To investigate the distribution of polymorphisms of SLC11A1 gene, VDR gene, MBL gene and IFNG gene with susceptibility to tuberculosis (TB) in Chinese Han population suffering from drug-sensitive TB and drug-resistant TB so as to identify the correlation between gene polymorphisms and the development of drug-resistant TB.
Methods: Single nucleotide polymorphisms (SNP) of VDR gene, SLC11A1 gene, MBL gene, IFNG gene were typed and analyzed by pyrosequencing, Real-time Probe and SNaPshot among 229 patients with drug-sensitive TB and 230 patients with drug-resistant TB.
Results: The polymorphic foci of VDR gene from the drug-sensitive TB group and the drug-resistant TB group showed no significant difference (P > 0.05). The genotype of INT4 site and allelic frequency of SLC11A1 gene for drug-sensitive TB group were significantly different from those for drug-resistant TB group (P = 0.031, 0.046). If recessive inheritance was assumed, the genotypes of INT4 site from the two groups were significantly different (OR = 5.756, 95%CI: 1.261 - 26.269, P = 0.011). Considering the relationship between OR values under various combination, our findings confirmed that the genetic mode of INT4 site was in accordance with recessive inheritance. The genotypes of Q/P site and allelic frequencies of MBL gene from drug-sensitive and drug-resistant groups were significantly different (P = 0.029, 0.033). The difference still existed under the hypothesis of recessive inheritance (OR = 9.290, 95%CI: 1.167 - 73.949, P = 0.011). The polymorphic foci of IFNG gene from the two groups showed no significant difference.
Conclusion: INT4 sites on SLC11A1 gene and Q/P site on MBL gene were probably associated with the development of drug-resistant TB in Chinese Han population. Further study on this issue would be helpful in locating the population at high risk of drug-resistant TB and exploring the effective intervention to decrease the incidence of this disease.