Pulmonary Nontuberculous Mycobacterial Infection. A Multisystem, Multigenic Disease

• Published in: American journal of respiratory and critical care medicine Vol. 192; no. 5; pp. 618 - 628
• Main Authors: Szymanski, Eva P., Leung, Janice M., Fowler, Cedar J., Haney, Carissa, Hsu, Amy P., Chen, Fei, Duggal, Priya, Oler, Andrew J., McCormack, Ryan, Podack, Eckhard, Drummond, Rebecca A., Lionakis, Michail S., Browne, Sarah K., Prevots, D. Rebecca, Knowles, Michael, Cutting, Gary, Liu, Xinyue, Devine, Scott E., Fraser, Claire M., Tettelin, Hervé, Olivier, Kenneth N., Holland, Steven M.
• Format: Journal Article
• Language: English
• Published: United States American Thoracic Society 01.09.2015
• Subjects: Adult; Aged; Aged, 80 and over; Case-Control Studies; Causality; Cilia - genetics; Cohort Studies; Connective Tissue; Cystic Fibrosis Transmembrane Conductance Regulator - genetics; Exome; Family; Female; Genetic Predisposition to Disease; Genetic Variation; Humans; Immunity - genetics; Male; Middle Aged; Mycobacterium Infections, Nontuberculous - genetics; Original; Principal Component Analysis; Sequence Analysis, DNA; Tuberculosis, Pulmonary - genetics; nontuberculous mycobacteria; cilia; genetics; bronchiectasis; immune system diseases
• DOI: 10.1164/rccm.201502-0387OC
• ISSN: 1073-449X; 1535-4970

The clinical features of patients infected with pulmonary nontuberculous mycobacteria (PNTM) are well described, but the genetic components of infection susceptibility are not. To examine genetic variants in patients with PNTM, their unaffected family members, and a control group. Whole-exome sequencing was done on 69 white patients with PNTM and 18 of their white unaffected family members. We performed a candidate gene analysis using immune, cystic fibrosis transmembrance conductance regulator (CFTR), cilia, and connective tissue gene sets. The numbers of patients, family members, and control subjects with variants in each category were compared, as was the average number of variants per person. A significantly higher number of patients with PNTM than the other subjects had low-frequency, protein-affecting variants in immune, CFTR, cilia, and connective tissue categories (35, 26, 90, and 90%, respectively). Patients with PNTM also had significantly more cilia and connective tissue variants per person than did control subjects (2.47 and 2.55 compared with 1.38 and 1.40, respectively; P = 1.4 × 10(-6) and P = 2.7 × 10(-8), respectively). Patients with PNTM had an average of 5.26 variants across all categories (1.98 in control subjects; P = 2.8 × 10(-17)), and they were more likely than control subjects to have variants in multiple categories. We observed similar results for family members without PNTM infection, with the exception of the immune category. Patients with PNTM have more low-frequency, protein-affecting variants in immune, CFTR, cilia, and connective tissue genes than their unaffected family members and control subjects. We propose that PNTM infection is a multigenic disease in which combinations of variants across gene categories, plus environmental exposures, increase susceptibility to the infection.