Study on the correlation of natural-resistance-associated macrophage protein 1 gene with susceptibility to pulmonary tuberculosis in Yunnan Han population

ObjectiveTo investigate the correlation between the polymorphisms of D543N and INT4 locus of natural-resistance-associated macrophage protein 1(NRAMP1) gene and susceptibility to pulmonary tuberculosis.

MethodsA case-control study was conducted.One hundred and twenty-two Yunnan Han nationality patients with positive sputum smear were set as the case group, and 101 healthy physical examiners with nationality, age and gender matching with the case group were set as the control group at the same period.The polymerase chain reaction and restriction fragment length polymorphism technique were used to type the D543N and INT4 polymorphisms of NRAMP1 gene in two groups.

ResultsThe distribution frequencies of wild homozygotes(G/G), heterozygotes(G/C) and mutant homozygotes(C/C) at the INT4 locus were 66.4%, 32.0% and 1.6% in the case group, and 86.1%, 12.9% and 1.0% in control group, respectively, the difference of which between two groups was statistically significant(P < 0.01), and the risk of tuberculosis in heterozygous(G/C) carriers was 3.22 times that of wild homozygous(G/G)(95%CI:1.61~6.47).The distribution frequencies of wild homozygotes(G/G), heterozygotes(G/A) and mutant homozygotes(A/A) at the D543N locus were 61.5%, 36.9% and 1.6% in case group, and 70.3%, 29.7% and 0% in control group, respectively, and the difference of which was not statistically significant(P>0.05).

ConclusionsThe polymorphism of INT4 locus of NRAMP1 gene may affect the susceptibility to pulmonary tuberculosis in Yunnan Han population.