Although tuberculosis (TB) is a serious public health concern, we still don't understand why only 10% of people infected will develop the disease. Apoptosis plays a role in the interaction of Mycobacterium tuberculosis (Mtb) with the human host and it may be modified by subtle alterations in the B-cell lymphoma 2 (BCL2) gene, an anti-apoptotic regulatory element. Therefore, we investigated whether there is an association between BCL2 polymorphisms and susceptibility to TB by analyzing 130 TB cases, 108 subjects with latent TB infection (LTBI), and 163 healthy controls (HC). Logistic regression was used to calculate odds ratios (ORs) and 95% confidential intervals (95% CIs) for possible associations between single nucleotide polymorphisms (SNPs) in BCL2 and the risk of tuberculosis. We found that the G allele of rs80030866 (OR=0.62, 95%CI:0.42-0.91, P=0.015), and also the G allele of rs9955190 (OR=0.58, 95%CI:0.38-0.88, P=0.011) were less frequent in the TB group compared with the LTBI group. In addition, individuals with rs2551402 CC genotype were more likely to have LTBI than those with AA genotype (OR=2.166, 95%CI:1.046-4.484, P=0.037). Our study suggests that BCL2 gene polymorphisms may be correlated with susceptibility to both TB and LTBI.

No abstract

Background: Nontuberculous mycobacterial (NTM) infections are becoming more common, but the epidemiologic characteristics of NTM in much of the world remain largely unknown. The purpose of this study was to evaluate the prevalence and risk factors for NTM infection in a southern coastal area of China.Results: 1759 individuals suspected of having tuberculosis were included in the analysis, of whom 140 (7.96%) had NTM isolated from their sputa. The NTM species identified by the Kraken 2/Bracken and Hain methods were highly consistent. M. abscessus complex bacilli were the most prevalent species isolated (n=58, 41.43%), followed by the Mycobacterium avium complex (MAC) (n=41, 29.29%). Residency in Shenzhen for more than 2 years (OR 4.205; 95% CI 1.851-9.552; P = 0.001) and a history of prior TB (OR 4.263; 95% CI 1.871-9.714; P = 0.001) increased the risk for NTM infections. Whole-genome sequencing data from many of the MAC isolates showed high genomic diversity and heterogeneity.Conclusion: M. abscessus was the most common causative NTM species found in symptomatic patients in this region. Living in Shenzhen for more than 2 years and having a previous history of TB were associated with an increased risk of NTM infection. MAC genomes are often heterogenous.

Background: Autophagy can inhibit the survival of intracellular microorganisms including Mycobacterium tuberculosis ( Mtb ) , and the PI3K/AKT/mTOR pathway plays a crucial role. This study investigated the association between PI3K/AKT/mTOR pathway autophagy-related gene polymorphisms and pulmonary tuberculosis (PTB) susceptibility. Methods: KEGG pathway and gene ontology (GO) databases were searched for genes belonging to the PI3K/AKT/mTOR and autophagy pathways. Thirty SNPs in nine genes were identified and tested for their associations with tuberculosis in 130 patients with PTB and 271 controls. We constructed genetic risk scores (GRSs) and divided the participants into 3 subgroups based on their GRSs:0-5, 6-10, and 11-16. Results: This analysis revealed that the AKT1 (rs12432802), RPTOR (rs11654508, rs12602885, rs2090204, rs2589144, and rs2672897), and TSC2 (rs2074969) polymorphisms were significantly associated with PTB risk. A decreasing trend was observed ( P trend 0.020), in which a lower GRS was associated with a higher risk of PTB ([6-10] vs. [0-5]: OR (95%CI) 0.590 (0.374-0.931); [11-16] vs. [0-5]: OR (95%CI) 0.381 (0.160-0.906)). Conclusions: Polymorphisms in AKT1, RPTOR, and TSC2 may influence susceptibility to PTB.