Association between chronic obstructive pulmonary disease and interleukins gene variants: A systematic review and meta-analysis

Association between single-nucleotide polymorphism of cytokines genes and chronic obstructive pulmonary disease: A systematic review and meta-analysis

Chronic obstructive pulmonary disease (COPD) is a common chronic inflammatory disease with high morbidity and mortality rates worldwide. Cytokines, which are the main regulators of immune responses, play crucial roles in inflammatory diseases such as COPD. Moreover, certain genetic variations can alter cytokine expression, and changes in cytokine level or function can affect disease susceptibility. Therefore, investigating the association between genetic variations and disease progression can be useful for prevention and treatment. Several studies have explored the association between common genetic variations in cytokine genes and COPD susceptibility. In this study, we summarized the reported studies and, where possible, conducted a systematic review and meta-analysis to evaluate the genetic association between various cytokines and COPD pathogenesis. We extracted relevant articles from PubMed and Google Scholar databases using a standard systematic search strategy. We included a total of 183 studies from 78 separate articles that evaluated 50 polymorphisms in 12 cytokine genes in this study. Our analysis showed that among all reported cytokine polymorphisms (including TNF-α, TGF-β, IL1, IL1RN, IL4, IL4R, IL6, IL10, IL12, IL13, IL17, IL18, IL27, and IL33), only four variants, including TNF-α-rs1800629, TGF-β1-rs6957, IL13-rs1800925, and IL6-rs1800796, were associated with the risk of COPD development. This updated meta-analysis strongly supports the association of TNF-α-rs1800629, TGF-β1-rs6957, IL13-rs1800925, and IL6-rs1800796 variants with a high risk of COPD.

IL13 Promoter (-1055) Polymorphism Associated with Leukocyte Mitochondria DNA Copy Number in Chronic Obstructive Pulmonary Disease

IL13 polymorphism is associated with chronic obstructive pulmonary disease (COPD). Patients with COPD have smaller numbers of mitochondria deoxyribonucleic acid copies (mtDNA-CN) than people without COPD do. However, whether IL13 polymorphism affects the mutation and recombination of mitochondria remains unclear. Data for patients with COPD and non-COPD were collected from Kaohsiung Chang Gung Memorial Hospital to enable a comparison of their leukocyte mtDNA-CN and the association of this information with IL-13 promoter (−1055) polymorphism. This study included 99 patients with COPD and 117 individuals without COPD. The non-COPD individuals included 77 healthy individuals that never smoked and 40 healthy smokers. The patients with COPD exhibited significantly lower mtDNA-CN than non-COPD did (250.34 vs. 440.03; p < 0.001); mtDNA-CN was particularly pronounced in individuals with the IL13 CC and CT genotypes compared with individuals with the TT genotype. When only individuals without COPD were considered and when all participants were considered, the differences in the mtDNA-CNs in individuals with the CC and CT genotypes were more significant than those in individuals with the TT genotype (448.4 and 533.6 vs. 282.8; p < 0.05 in non-COPD group); (368.8 and 362.6 vs. 249.6, p < 0.05 in all participants). The increase mtDNA-CN in the CC and CT genotypes was also more than that in the TT genotype in COPD patients, but showed no significance (260.1 and 230.5 vs. 149.9; p = 0.343). The finding shows that COPD is a mitochondria regulatory disorder and IL-13 promoter (−1055) polymorphism is associated with leukocyte mtDNA-CN. Developing COPD control methods based on mitochondrial regulation will be possible.

Genetic Variants Associated with Chronic Obstructive Pulmonary Disease Risk: Cumulative Epidemiological Evidence from Meta-Analyses and Genome-Wide Association Studies

Background

Last two decades, many association studies on genetic variants and chronic obstructive pulmonary disease (COPD) risk have been published. But results from different studies are inconsistent. Therefore, we performed this article to systematically evaluate results from previous meta-analyses and genome-wide association studies (GWASs). Material and Methods. Firstly, we retrieved meta-analyses in PubMed, Embase, and China National Knowledge Infrastructure and GWASs in PubMed and GWAS catalog on or before April 7th, 2022. Then, data were extracted and screened. Finally, two main methods—Venice criteria and false-positive report probability test—were used to evaluate significant associations.

Results

As a result, eighty-eight meta-analyses and 5 GWASs were deemed eligible for inclusion. Fifty variants in 26 genes obtained from meta-analyses were significantly associated with COPD risk. Cumulative epidemiological evidence of an association was graded as strong for 10 variants in 8 genes (GSTM1, CHRNA, ADAM33, SP-D, TNF-α, VDBP, HMOX1, and HHIP), moderate for 6 variants in 5 genes (PI, GSTM1, ADAM33, TNF-α, and VDBP), and weak for 40 variants in 23 genes. Five variants in 4 genes showed convincing evidence of no association with COPD risk in meta-analyses. Additionally, 29 SNPs identified in GWASs were proved to be noteworthy based on the FPRP test.

Conclusion

In summary, more than half (52.38%) of genetic variants reported in previous meta-analyses showed no association with COPD risk. However, 13 variants in 9 genes had moderate to strong evidence for an association. This article can serve as a useful reference for further studies.

Transmembrane protease serine 2 (TMPRSS2) rs75603675, comorbidity, and sex are the primary predictors of COVID-19 severity

The TMPRSS2 rs75603675 genotype (OR = 0.586), dyslipidemia (OR = 2.289), sex (OR = 0.586), and the Charlson Comorbidity Index (OR = 1.126) were identified as the main predictors of COVID-19 severity in 817 patients who attended Hospital Universitario de La Princesa during March and April 2020.

By the end of December 2021, coronavirus disease 2019 (COVID-19) produced more than 271 million cases and 5.3 million deaths. Although vaccination is an effective strategy for pandemic control, it is not yet equally available in all countries. Therefore, identification of prognostic biomarkers remains crucial to manage COVID-19 patients. The aim of this study was to evaluate predictors of COVID-19 severity previously proposed. Clinical and demographic characteristics and 120 single-nucleotide polymorphisms were analyzed from 817 patients with COVID-19, who attended the emergency department of the Hospital Universitario de La Princesa during March and April 2020. The main outcome was a modified version of the 7-point World Health Organization (WHO) COVID-19 severity scale (WHOCS); both in the moment of the first hospital examination (WHOCS-1) and of the severest WHOCS score (WHOCS-2). The TMPRSS2 rs75603675 genotype (OR = 0.586), dyslipidemia (OR = 2.289), sex (OR = 0.586), and the Charlson Comorbidity Index (OR = 1.126) were identified as the main predictors of disease severity. Consequently, these variables might influence COVID-19 severity and could be used as predictors of disease development.

Genome-wide association study identifies novel susceptibility loci for KIT D816V positive mastocytosis

Mastocytosis is a rare myeloid neoplasm characterized by uncontrolled expansion of mast cells, driven in >80% of affected individuals by acquisition of the KIT D816V mutation. To explore the hypothesis that inherited variation predisposes to mastocytosis, we performed a two-stage genome-wide association study, analyzing 1,035 individuals with KIT D816V positive disease and 17,960 healthy control individuals from five European populations. After quality control, we tested 592,007 SNPs at stage 1 and 75 SNPs at stage 2 for association by using logistic regression and performed a fixed effects meta-analysis to combine evidence across the two stages. From the meta-analysis, we identified three intergenic SNPs associated with mastocytosis that achieved genome-wide significance without heterogeneity between cohorts: rs4616402 (p_meta = 1.37 × 10^-15, OR = 1.52), rs4662380 (p_meta = 2.11 × 10^-12, OR = 1.46), and rs13077541 (p_meta = 2.10 × 10^-9, OR = 1.33). Expression quantitative trait analyses demonstrated that rs4616402 is associated with the expression of CEBPA (p_eQTL = 2.3 × 10^-14), a gene encoding a transcription factor known to play a critical role in myelopoiesis. The role of the other two SNPs is less clear: rs4662380 is associated with expression of the long non-coding RNA gene TEX41 (p_eQTL = 2.55 × 10^-11), whereas rs13077541 is associated with the expression of TBL1XR1, which encodes transducin (β)-like 1 X-linked receptor 1 (p_eQTL = 5.70 × 10^-8). In individuals with available data and non-advanced disease, rs4616402 was associated with age at presentation (p = 0.009; beta = 4.41; n = 422). Additional focused analysis identified suggestive associations between mastocytosis and genetic variation at TERT, TPSAB1/TPSB2, and IL13. These findings demonstrate that multiple germline variants predispose to KIT D816V positive mastocytosis and provide novel avenues for functional investigation.