Role of ADAM33 gene and associated single nucleotide polymorphisms in asthma

Genetic Variants Associated with Bronchial Asthma Specific to the Population of the Russian Federation

Bronchial asthma (BA) is a disease that still lacks an exhaustive treatment protocol. In this regard, the global medical community pays special attention to the genetic prerequisites for the occurrence of this disease. Therefore, the search for the genetic polymorphisms underlying bronchial asthma has expanded considerably. As the present study progressed, a significant amount of scientific medical literature was analyzed and 167 genes reported to be associated with the development of bronchial asthma were identified. A group of participants (n = 7,303) who had voluntarily provided their biomaterial (venous blood) to be used in the research conducted by the Federal Medical Biological Agency of Russia was formed to subsequently perform a bioinformatic verification of known associations and search for new ones. This group of participants was divided into four cohorts, including two sex-distinct cohorts of individuals with a history of asthma and two sex-distinct cohorts of apparently healthy individuals. A search for polymorphisms was made in each cohort among the selected genes, and genetic variants were identified whose difference in occurrence in the different cohorts was statistically significant (significance level less than 0.0001). The study revealed 11 polymorphisms that affect the development of asthma: four genetic variants (rs869106717, rs1461555098, rs189649077, and rs1199362453), which are more common in men with bronchial asthma compared to apparently healthy men; five genetic variants (rs1923038536, rs181066119, rs143247175, rs140597386, and rs762042586), which are more common in women with bronchial asthma compared to apparently healthy women; and two genetic variants (rs1219244986 and rs2291651) that are rare in women with a history of asthma.

C5 and SRGAP3 Polymorphisms Are Linked to Paediatric Allergic Asthma in the Italian Population

Asthma is a complex and heterogeneous disease, caused by the interaction between genetic and environmental factors with a predominant allergic background in children. The role of specific genes in asthmatic bronchial reactivity is still not clear, probably because of the many common pathways shared with other allergic disorders. This study is focused on 11 SNPs possibly related to asthma that were previously identified in a GWAS study. The genetic variability of these SNPs has been analysed in a population of 773 Italian healthy controls, and the presence of an association between the polymorphisms and the asthma onset was evaluated performing genotyping analysis on 108 children affected with asthma compared with the controls. Moreover, a pool of 171 patients with only allergic rhinoconjunctivitis has been included in the case-control analysis. The comparison of allele frequencies in asthmatic patients versus healthy controls identified two SNPs-rs1162394 (p = 0.019) and rs25681 (p = 0.044)-associated with the asthmatic condition, which were not differentially distributed in the rhinoconjunctivitis group. The rs25681 SNP, together with three other SNPs, also resulted in not being homogenously distributed in the Italian population. The significantly higher frequency of the rs25681 and rs1162394 SNPs (located, respectively, in the C5 and SRGAP3 genes) in the asthmatic population suggests an involvement of these genes in the asthmatic context, playing a role in increasing the inflammatory condition that may influence asthma onset and clinical course.

Haplotype analysis of ADAM33 polymorphisms in asthma: A pilot study

Background & objectives

ADAM33 is implicated as a potentially strong candidate gene for asthma and bronchial hyper-responsiveness. Many polymorphisms of ADAM33 have been studied along with ADAM33 expression in various cells of the lungs. Haplotype analysis also showed association with asthma in different populations across the world. Therefore, the aim of this study was to perform a comprehensive screening of ADAM33 polymorphisms in adult patients with asthma.

Methods

Thirty five polymorphisms of ADAM33 were genotyped in 55 patients with asthma and 53 controls. The association of single nucleotide polymorphisms (SNPs) and haplotypes with phenotypes of asthma was analysed.

Results

The genotype, minor allele frequency, odds ratio and Hardy-Weinberg equilibrium did not show any significant difference among cases and controls. No association was found between SNPs of ADAM33 with the severity of asthma. Correlation analysis of ADAM33 SNPs to the phenotypes, based on clinical variables and allergen sensitization, did not show significant difference. Haplotype analysis showed that rs2280090 and rs2280091 were associated with asthma in the patient group.

Interpretation & conclusions

Haplotype analysis showed an association of the two SNP variations with asthma. These SNPs lead to amino acid change and are prone to phosphorylation, which may affect expression levels and protein function of ADAM33 and asthma susceptibility.

Association of ADAM33 gene polymorphisms with asthma in Mongolian and Han groups in Inner Mongolia

Polymorphisms in the gene encoding for A disintegrin and metalloprotease 33 (ADAM33) are closely associated with the risk of bronchial asthma attacks in different populations. We collected blood samples from 248 asthma patients - 130 of the Han ethnic group and 118 of the Mongolian ethnic group - living in the Inner Mongolia region of China, and analyzed the single nuclear polymorphisms (SNPs) of the T1, T2 and V4 loci of the ADAM33 gene using PCR-RFLP (restriction fragment length polymorphism). In addition, we also tested 256 healthy controls (134 and 122 from the Han and Mongolian ethnic groups respectively) for the same SNPs. Three genotypes of the T1, T2 and V4 loci were predominantly detected: while polymorphisms in the T1 locus were significantly associated with asthma risk in both Mongolian and Han ethnicities (P < 0.05, ∗P < 0.05), that in the V4 locus were relevant only in the Mongolian patients (P < 0.05, ∗P > 0.05). In contrast, polymorphisms in the T2 locus showed no significant association with asthma risk in either ethnic group (P > 0.05, ∗P > 0.05).

Single nucleotide polymorphisms in asthma candidate genes TBXA2R, ADAM33 FCER1B and ORMDL3 in Pakistani asthmatics a case control study

BACKGROUND

Genetic variations in different loci and genes are important in asthma pathogenesis. There is much importance of various immunological pathways in the IgE secretion regulation. Alterations in any main part of these pathways can increase the risk of asthma development. Polymorphisms in these genetic markers can effect certain pathways which predict the asthma susceptibility. In the present study, SNPs directly or indirectly affecting the immunological process pathways are selected.

METHODS

This study was conducted to determine association of 16 SNPs in 10 candidate genes with asthma in Pakistani population in 333 asthmatic cases and 220 healthy controls. Genotyping was performed using the Sequenom Mass ARRAY iPLEX platform (14 SNPs) and TaqMan assay (2 SNPs).

RESULTS

The minor allele at two of the SNPs showed association with protection from asthma, rs1131882 in TBXA2R gene (OR 0.73, 95% CI 0.52-1.01, P = 0.05) and rs2280091 in the ADAM33 gene (OR 0.69, 95% CI 0.50-0.97, P = 0.03). For FCER1B gene, rs2583476 the asthmatic male gender had higher TT genotype counts as compared to controls (OR = 1.86, 95% CI = 1.09-3.17, p = 0.01). In rs11650680 of ORMDL3 gene the CT genotype is more prevalent in female asthma cases in comparison with female controls (OR = 1.99, 95% CI = 1.02-3.89, p = 0.03).

CONCLUSIONS

This data suggests that variations at TBXA2R and ADAM33 genes are found to be associated with asthma susceptibility in Pakistan. FCER1B gene is associated with male and ORMDL3 in female asthmatics. These genetic markers can be important source of asthma risk in Pakistani population.

Comorbidities Associated with Psoriatic Arthritis Compared with Non-psoriatic Spondyloarthritis: A Cross-sectional Study

OBJECTIVE

Psoriatic arthritis (PsA) is a chronic inflammatory skeletal disease associated with health concerns such as obesity, Type II diabetes, dyslipidemia, hypertension (HTN), and cardiovascular (CV) disease. The involvement of these metabolic factors in the pathogenesis, severity, and progression of PsA remains unclear. In our study, we compared comorbidities associated with PsA to those patients with related but non-PsA forms of spondyloarthritis (SpA).

METHODS

The SpA database at the Rheumatology Department of University Hospitals Leuven was analyzed in a cross-sectional manner using the demographic, medical, and laboratory information of 518 patients with PsA and non-PsA SpA. The patients were grouped by their diagnosis and evaluated on the basis of sex, age, education, work status, disease duration, treatment, and type and number of comorbidities. The data were assessed using the chi-square test, Student t test, Fisher's exact test, and logistic regression, including correction for multiple testing.

RESULTS

Out of the 518 patients (62.74% men, 37.25% women), 53.66% had comorbidities. The PsA group had 262 patients (mean age 58.8 yrs) and the non-PsA SpA group had 256 patients (mean age 44.9 yrs, p < 0.001). The PsA group was found to have more and multiple comorbidities compared with non-PsA SpA (p < 0.001). The CV and metabolic comorbidities were also significantly higher in the PsA group (p < 0.001). Coronary artery disease, HTN, hyperlipidemia, and metabolic syndrome showed a marked difference between the 2 groups (p < 0.05). An increased incidence of malignancy was found in PsA group (p < 0.05).

CONCLUSION

Comorbidities and malignancies are increased in patients with PsA compared with non-PsA SpA, irrespective of demographic factors and type of treatment.

The roles of ADAM33, ADAM28, IL-13 and IL-4 in the development of lung injuries in children with lethal non-pandemic acute infectious pneumonia

BACKGROUND

ADAM28, ADAM33, IL-13, IL-4 and other cytokines (IL-6 and IL-10) seem to play important roles in the persistence and maintenance of acute inflammatory processes that ultimately lead to lung remodeling and pulmonary fibrosis, which may be responsible for the high morbidity and mortality rates associated with non-pandemic acute viral pneumonias in childhood.

OBJECTIVES

The aim of this study was to evaluate the roles of ADAM33, ADAM28, IL4, IL6, IL10 and IL13 in the development of inflammation and alveolar fibrosis due to lethal acute respiratory infections of the lower airway in a pediatric population, especially in those with viral etiology.

STUDY DESIGN

For this study, 193 cases were selected, and samples from the cases were processed for viral antigen detection by immunohistochemistry and then separated into two groups: virus-positive (n=68) and virus-negative (n=125). Immunohistochemistry was performed to assess the presence of metalloproteinases (ADAM33 and ADAM28) and inflammatory cytokines (IL-4, IL-13, IL-6, IL-10) in the alveolar septa.

RESULTS

The virus-positive group showed stronger immunolabeling for ADAM33, ADAM28, IL-4 and IL-13 (p<0.0001 for all variables). The staining intensities for ADAM33 and ADAM28 were directly proportional to the intensities for IL-4 and IL-13 (p<0.0001).

CONCLUSIONS

The results of this study suggest that these proteins play important roles in pulmonary inflammatory reactions elicited against etiological viral agents. In addition, these mediators may affect the process of lung remodeling and the development of pulmonary fibrosis.

Association of ADAM33 gene polymorphisms with allergic asthma

OBJECTIVES

Asthma results from the interaction between genetic and environmental factors. ADAM33 gene on chromosome 20p13 is associated with asthma and airway hyperresponsiveness.

MATERIALS AND METHODS

This is a case-control study, where four SNPs S1 (rs3918396), T1 (rs2280091), T2 (rs2280090), V4 (rs2787094) of ADAM33 gene have been assessed in patients with allergic asthma and normal controls (95 patients and 86 normal). Blood samples of these participants have been genotyped by PCR and the RFLP method.

RESULTS

There was no association between asthmatic patients and polymorphisms of alleles, genotypes and haplotypes of the ADAM33 gene. When categorizing the asthmatic patients in severe, moderate and mild groups, associations in the subcategories of asthmatic patients were found. There were associations between polymorphisms of C allele of T1 SNP with severe asthmatic patients and G allele of V4 SNP with moderate asthmatics respectively (P=0.006, P=0.01). There was a significant association between sensitivity to mite and polymorphism of C allele of T1 SNP (P=0.02). Besides, there was a significant association between sensitivity to weeds and genotype GG of V4 SNP (P=0.05).

CONCLUSION

Polymorphisms of ADAM33 gene might be associated with severe asthma and sensitivity to aeroallergens in northeast of Iran, but further studies are needed to determine the polymorphisms in this area and other regions of our country.

Molecular interaction network and pathway studies of ADAM33 potentially relevant to asthma

BACKGROUND

Asthma is a complex disease caused by gene-gene, gene-protein, and protein-protein interactions and the influence of environment, which plays a significant role in causing asthma pathogenesis. ADAM33 is known to be an important gene involved in asthma pathogenesis. No one single gene is a causal factor of asthma; rather, asthma is caused by a complex interaction of multiple genes having pathogenetic and protective effects.

OBJECTIVE

To identify and understand the interacting genes and proteins of ADAM33.

METHODS

The Ingenuity Pathway Analysis and GeneMANIA tools and a literature survey were used to identify the interacting candidates of ADAM33 and the WEB-based GEne SeT AnaLysis Toolkit was used to perform enrichment analysis of the proteins identified.

RESULTS

Keeping ADAM33 as a major hub, the authors identified some proteins whose interaction with ADAM33 had been associated with asthma and they recognized some proteins, such as amyloid β (A4) precursor protein, ataxin-7, α4-integrin, α5-integrin, α9-integrin, tissue inhibitor of metalloproteinase-4, and ubiquilin-4, that had not been previously associated with asthma.

CONCLUSION

The proteins identified in this study were enriched for various mechanisms that are involved in airway hyperresponsiveness, and through the interaction with ADAM33, they may have potential relevance in asthma.

Genetic variation of TBX21 gene increases risk of asthma and its severity in Indian children

T-box transcription factor protein (TBX21) is encoded by the TBX21 gene in human. It is crucial for naive T lymphocyte development, interferon-γ production, airway hyperresponsiveness and regulation of corticosteroid response in asthmatics. Polymorphisms rs4794067 and rs16947078 of TBX21 were found to be associated with acetylsalicylic acid-induced and allergic asthma, respectively. We examined whether sequence variants of TBX21 gene are associated with asthma and its severity in Indian population. In a hospital-based case-control study, 240 asthmatic children and 240 healthy controls were investigated for the association of TBX21 rs4794067 (C>T) and rs16947078 (G>A) polymorphisms with asthma and its severity using PCR-restriction fragment length polymorphism method. Heterozygous (CT) (odds ratio (OR)=2.33; P=0.001) and variant (TT) (OR=6.25; P=0.001) genotypes of rs4794067 were demonstrated significant risk of asthma. However, in asthma severity variant (TT) genotype revealed significant increase risk (intermittent: OR=5.9, P=0.001; mild: OR=8.0, P=0.001; moderate: OR=3.2, P=0.041; and severe: OR=43.6, P=0.001) in all subgroups. Furthermore, haplotypes TG (OR=2.83; P=0.001) and TA (OR=2.54; P=0.001) of TBX21 were associated with an increased risk of asthma. Conversely, rs16947078 G>A polymorphism was not associated with any asthma/asthma severity risk. These data suggest that TBX21 gene variation may modify individual's susceptibility to asthma and its severity in Indian population. However, further validation in large population-based studies is needed to confirm the finding.

Association of a disintegrin and metalloprotease 33 gene polymorphisms with asthma

Various studies reported a disintegrin and metalloprotease 33 (ADAM33) as an important susceptibility gene for asthma, which is frequently detected among certain populations. The aim of the present study was to investigate the association between single-nucleotide polymorphisms (SNPs) of the ADAM33 gene and asthma. Our case-control study included 183 patients (73 male and 110 female, mean age 42.93±13.48 years) who were admitted in the First Affiliated Hospital of Xinjiang Medical University between February, 2012 and May, 2013 and 155 healthy controls (66 male and 89 female, mean age 41.14±14.10 years). Allele-specific polymerase chain reaction technology and DNA testing training methods were applied to detect the T2 and ST+5 polymorphisms of the ADAM33 gene. The data were statistically analyzed to determine whether there exists an association between these genotypes and asthma-related morbidity. The genotypes and allele frequencies of the T2 and ST+5 SNPs of ADAM33 were not found to be significantly associated with asthma risk when compared between asthmatic patients and healthy controls (P>0.05). In addition, there was no association of the investigated SNPs with the severity of asthma. There was no significant difference in the forced vital capacity and the forced expiratory volume between patients with the ADAM33 T2 and ST+5 genotype. In conclusion, our results suggested that the T2 and ST+5 ADAM33 gene polymorphisms do not confer a significant risk of asthma or affect its severity in the population investigated.

Association between ADAM33 S2 and ST+4 polymorphisms and susceptibility to asthma: a meta-analysis

OBJECTIVE

The aim of this study was to determine whether ADAM33 (a disintegrin and metalloproteinase domain 33) polymorphisms confer susceptibility to asthma in different populations.

METHODS

We performed a meta-analysis on the association between the ADAM33 S2, ST+4, F+1, S1, and V4 polymorphisms and asthma.

RESULTS

Thirteen studies in ten reports, which included 4942 patients and 7933 controls, were available for the meta-analysis. Meta-analysis stratified by ethnicity indicated an association between the ADAM33 S2 2 allele and asthma in Europeans (OR=0.912, 95% CI=0.851-0.977, p=0.009). Meta-analysis revealed an association between asthma and the ADAM33 ST+4 2 allele (OR=0.783, 95% CI=0.762-0.999, p=0.048). Stratification by ethnicity indicated an association between the ADAM33 ST+4 polymorphism and asthma in Asians. Stratification by age indicated an association between the ADAM33 ST+4 2 allele and asthma in adults (OR=0.863, 95% CI=0.782-0.964, p=0.008). However, no association was found between asthma and the ADAM33 F+1, S1, and V4 polymorphisms.

CONCLUSIONS

This meta-analysis demonstrates that the ADAM33 S2 polymorphism confers susceptibility to asthma in Europeans and the ADAM33 ST+4 polymorphism is associated with asthma in Asians and adults.

Increased expression of ADAM33 protein in asthmatic patients as compared to non-asthmatic controls

BACKGROUND & OBJECTIVES

ADAM33 is a member of a family of genes that encode membrane-anchored proteins with a disintegrin and a metalloprotease domain, primarily expressed in lung fibroblasts and bronchial smooth muscle cells. ADAM33 has been identified as a risk factor for asthma and is known as a gene associated with airway remodelling. The present study was conducted with the aims to investigate the expression of ADAM33 protein in patients of asthma and non-asthmatic controls, and to assess if the expression of ADAM33 protein relates with severity of asthma.

METHODS

A total of 35 subjects, including 27 patients with asthma and eight non-asthmatic controls were included using Global Initiative for Asthma guidelines 2005. Bronchial biopsy tissues were collected and paraffin sections were made to store all study samples. Immunohistochemistry was performed using standardized protocol.

RESULTS

An increase in expression of ADAM33 protein was observed in the epithelium, smooth muscle and mesenchymal cells of asthma cases when compared to controls but there was no relationship with severity of asthma.

INTERPRETATION & CONCLUSIONS

A higher expression of ADAM33 protein was seen in asthma patients compared to controls. Large prospective studies need to be done with adequate study design to confirm these preliminary finding.

A disintegrin and metalloprotease 33 (ADAM33) gene polymorphisms and the risk of asthma: a meta-analysis

Polymorphisms in the ADAM33 gene have been associated with asthma, but the data are controversial. Therefore, we reviewed the related studies and quantitatively summarized the associations between ADAM33 polymorphisms and asthma risk using meta-analysis. A dominant model (AA+Aa vs. aa), recessive model (AA vs. Aa+aa), additive model (AA vs. aa) and allelic model (A vs. a) were used to estimate the association between ADAM33 polymorphism and asthma risk. A total of 29 case-control studies referring to 14 SNPs were identified: rs2280091(T1), rs2787094(V4), rs528557(S2), rs2280090(T2), rs511898(F+1), rs44707(ST+4), rs3918396(S1), rs543749(V-1), rs574174(ST+7), rs597980(ST+5), rs2853209(S+1), rs2280089(T+1), rs612709(Q-1), and rs3746631(V5). The results indicated that S1, V-1, V5, S+1, S2, ST+4, ST+7, ST+5, and Q-1 were not associated with asthma. Significant associations were found with the T1, V4, F+1 and T+1 polymorphisms in the overall population. In the subgroup analysis by ethnicity, a positive result was only found for the T1, V4, F+1 and T2 polymorphisms in Asia but not in Europe or Latin America. This meta-analysis provides evidence that the T1, V4, F+1, T2, and T+1 polymorphisms in the ADAM33 gene are risk factors for asthma, especially in the Asian population.