NRAMP1 gene polymorphism and susceptibility to nontuberculous mycobacterial lung diseases.
OBJECTIVE
Pulmonary disease caused by nontuberculous mycobacteria (NTM) may occur in patients with no underlying lung disease and no known immunodeficiency. The purpose of this study was to evaluate a potential role for natural-resistance-associated macrophage protein 1 (NRAMP1) gene polymorphisms for human susceptibility to the NTM lung disease.


METHODS
A case-control study.


METHODS
Tertiary university medical center.


METHODS
Forty-one adult patients with NTM lung disease (Mycobacterium avium complex infection, 18 patients; Mycobacterium abscessus infection, 23 patients) were included in the study population. The diagnosis of NTM lung disease was made when the patients fulfilled the diagnostic criteria published by the American Thoracic Society. All patients had findings on high-resolution CT scans, such as bilateral bronchiectasis combined with multiple small nodules and branching linear structures, that were characteristic of the nodular bronchiectatic form of NTM lung disease. Fifty healthy individuals were selected as control subjects.


RESULTS
Heterozygotes at intron 4 (469 + 14G/C) [INT4], codon 543 in exon 15 (D543N), and 3' untranslated region (3'UTR) were observed at significantly higher frequencies in patients with NTM lung disease than in control subjects. The odds ratios (ORs) were 2.78 (95% confidence interval [CI], 1.12 to 6.89; p = 0.026) for INT4 G/C, 5.74 (95% CI, 1.48 to 22.30; p = 0.006) for D543 G/A, and 9.54 (95% CI, 2.49 to 36.53; p < 0.001) for 3'UTR TGTG+/del. Subjects who were heterozygous for two NRAMP1 polymorphisms in INT4 and D543N were particularly overrepresented among those with NTM lung disease, compared with those with the most common NRAMP1 genotype (OR, 10.88, 95% CI, 1.18 to 100.45; p = 0.035). There were no significant differences in the frequencies of INT4, D543N, and 3'UTR polymorphisms between the patients with M avium complex infection and those with M abscessus infection.


CONCLUSIONS
These findings suggest that the NRAMP1 genetic polymorphisms are associated with human susceptibility to NTM lung disease.
Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-Dong, Gangnam-gu, Seoul 135-710, South Korea.
Won-Jung
WJ
Koh
O Jung
OJ
Kwon
Eun Joo
EJ
Kim
Kyung Soo
KS
Lee
Chang-Seok
CS
Ki
Jong Won
JW
Kim
D000328:Adult; D000368:Aged; D000483:Alleles; D016022:Case-Control Studies; D027682:Cation Transport Proteins / Q000235:genetics*; D016009:Chi-Square Distribution; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D016015:Logistic Models; D008171:Lung Diseases / Q000235:genetics* / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D009165:Mycobacterium Infections, Nontuberculous / Q000235:genetics*; D011110:Polymorphism, Genetic; D000099173:Natural Resistance-associated Macrophage Protein 1
D027682:Cation Transport Proteins; D000099173:Natural Resistance-associated Macrophage Protein 1