Novel Genetic Loci for Nontuberculous Mycobacterial Pulmonary Disease and Potential Protective Effect of Body Mass Index.

Rationale: Although nontuberculous mycobacteria (NTM) are widespread, only some individuals develop NTM pulmonary disease (NTM-PD), suggesting the involvement of host factors.

Objectives

To identify the genomic structure of NTM-PD and determine whether a definitive association exists between NTM-PD and nine risk factors.

Methods

We performed genome-wide association studies in two independent Korean cohorts involving 1,949 patients with NTM-PD and 2,955 healthy participants. Significantly associated genetic variants were validated in Japanese (1,137 cases, 1,546 controls) and European (243 cases, 570 controls) cohorts, respectively. Genes associated with lead variants were identified and their roles in NTM-PD were supported by single-cell transcriptome datasets. Genetic correlations and Mendelian randomization between NTM-PD and nine risk factors were examined. Measurements and Main

Results

We identified two novel loci and replicated a locus associated with NTM-PD: rs60084385 (odds ratio [OR], 1.34; 95% confidence interval [CI], 1.21-1.48; P = 6.97 × 10-9), rs1479595 (OR, 1.40; 95% CI, 1.27-1.55; P = 7.08 × 10-11), and rs194792 (OR, 1.70; 95% CI, 1.50-1.93; P = 1.39 × 10-16). These associations were replicated in the independent cohorts. The three loci were significantly associated with expression of IL1Rs, PDE8B (phosphodiesterase 8B), and PRKCB (protein kinase C β), respectively, whose involvement in the pathogenesis of NTM-PD was further validated. Among the risk factors, only body mass index demonstrated both a significant genetic correlation with NTM-PD (rg, -0.57; false discovery rate, 1.33 × 10-5) and a potential causal relationship (OR, 0.38; 95% CI, 0.24-0.59; false discovery rate, 8.55 × 10-5).

Conclusions

Our study identified three genetic loci associated with NTM-PD and a negative association of body mass index with NTM-PD.