Roles of genotypes of beta2-adrenergic receptor in the relationship between eosinophil counts and lung function in Taiwanese adolescents

Association of β2-adrenergic receptor gene polymorphisms (rs1042713, rs1042714, rs1042711) with asthma risk: a systematic review and updated meta-analysis

Background

The published data on the association between β2-adrenergic receptor gene polymorphisms and asthma susceptibility are inconclusive. To derive a more precise estimation of this association, a meta-analysis was performed.

Methods

A literature search was conducted in PubMed, Web of Science, EMBASE, Wanfang, and the China National Knowledge Infrastructure (CNKI) databases to identify eligible studies. The pooled odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were used to calculate the strength of the association. A sensitivity analysis was performed to evaluate the influence of individual studies on the overall effect estimates, and funnel plots and Egger’s tests were used for indications of publication bias.

Results

Seventy three studies with three single nucleotide polymorphisms (SNP) (rs1042713, c.G46A, p.Gly16Arg; rs1042714, c.G79C, p.Gln27Glu; rs1042711, c.T-47C, p.Cys19Arg) were finally identified. For the rs1042713 polymorphism, no significant association with asthma risk was found in the overall population. However, a significant protective association was found in the Indian population in the dominant model comparison (OR = 0.72, 95% CI = 0.59–0.87, I² = 25%, studies = 5, cases = 1190, controls = 1241). A significant risk association was found in the Arab population in the dominant model comparison (OR = 1.75, 95% CI = 1.14–2.70, I² = 0%, studies = 2, cases = 307, controls = 361) and the homozygote model comparison (OR = 1.88, 95% CI = 1.17–3.02, I² = 0%, studies = 2, cases = 307, controls = 361), and in the Hispanic-Latino population in the dominant model comparison (OR = 1.68, 95% CI = 1.10–2.55, I² = 77%, studies = 5, cases = 1026, controls = 1412). For the rs1042714 polymorphism, we found a significant association in the recessive model comparison (OR = 0.83, 95% CI = 0.70–0.98, I² = 44%, studies = 52, cases = 8242, controls = 16,832), the homozygote genotype comparison (OR = 0.84, 95% CI = 0.72–0.98, I² = 25%, studies = 52, cases = 8242, controls = 16,832) and the allelic genetic model (OR = 0.91, 95% CI = 0.83–0.99, I² = 59%, studies = 52, cases = 8242, controls = 16,832) in the overall population. When stratified by age, a significant association was also found in children in the recessive model comparison (OR = 0.59, 95% CI = 0.39–0.88, I² = 58%, studies = 18, cases = 2498, controls = 2510) and the homozygote genotype comparison (OR = 0.63, 95% CI = 0.43–0.92, I² = 46%, studies = 18, cases = 2498, controls = 2510), but not in adult. For the rs1042711 polymorphism, no significant associations were found in the any genetic model.

Conclusion

The meta-analysis suggests that the ADRB2 rs1042714 polymorphism has a protective association with asthma in the overall population and the pediatric subgroup.

The C79G Polymorphism of the β2-Adrenergic Receptor Gene, ADRB2, and Susceptibility to Pediatric Asthma: Meta-Analysis from Review of the Literature

Background

The ADRB2 gene encodes the β2-adrenergic receptor (β2-AR). This study aimed to determine the association between the C79G polymorphism of the ADRB2 gene and its association with pediatric asthma using a meta-analysis of the published data.

Material/Methods

Review of publications up to May 2018 was from the PubMed, EMBASE, China National Knowledge Infrastructure (CNKI), and WanFang databases. The odds ratio (ORs) with 95% confidence interval (CI) were used in evaluating the strength of the reported association between the C79G polymorphism of the ADRB2 gene and pediatric asthma.

Results

There were 18 controlled studies that included 2,982 pediatric cases of asthma and 2,651 controls. Expression of the C79G polymorphism of the ADRB2 gene was significantly associated with risk of pediatric asthma associated with the C or G allele with comparison of the co-dominant model (GG vs. CC: OR, 0.69; 95% CI, 0.55–0.88) and the recessive model (GG vs. CC+CG: OR, 0.65; 95% CI, 0.53–0.81). Subgroup analysis by ethnicity showed a significantly reduced risk of pediatric asthma in Asian patients for comparison of the co-dominant model (GG vs. CC: OR, 0.59; 95% CI, 0.45–0.78), the recessive model (GG vs. CC+CG: OR, 0.58; 95% CI, 0.45–0.76), and the allelic model (G vs. C: OR, 0.89; 95% CI, 0.79–0.99).

Conclusions

The C79G polymorphism of the ADRB2 gene encoding β2-AR was associated with a reduced risk for the development of pediatric asthma, particularly in the Asian population.

Beta 2 Adrenergic Receptor Genetic Polymorphisms in Bronchial Asthma: Relationship to Disease Risk, Severity, and Treatment Response

BACKGROUND

The β₂-adrenergic receptor gene is one of the most extensively studied genes with respect to asthma prevalence and severity. The Arg16Gly and Gln27Glu polymorphisms in the β₂-adrenergic receptor gene cause changes in the amino acids sequence of the receptor which may cause alteration in response to bronchodilators and the risk of asthma.

OBJECTIVE

The purpose of the study was to determine the association between β₂-adrenergic receptor gene polymorphisms and asthma risk, severity and response to therapy.

SUBJECTS AND METHODS

58 asthmatic patients and 38 healthy subjects were included. The β₂-adrenergic receptor polymorphisms genotyping was done using Real-Time polymerase chain reaction.

RESULTS

The allelic frequencies for the Arg16Gly polymorphism were 15.5%, 48.3%, and 36.2% for the homozygous A wild, heterozygous, and homozygous G mutant alleles in asthmatics (P < 0.01) and 5.3%, 47.4%, and 47.4% in healthy subjects (P < 0.01). For the Gln27Glu polymorphism, the allelic frequencies for the homozygous C wild, heterozygous and homozygous G mutant alleles were 51.7%, 41.4%, and 6.9% in asthmatics (P < 0.01) and 44.7%, 39.5%, and 15.8% in healthy subjects (P < 0.01). The heterozygous Arg16Gly and Gln27Glu were found in most of severe asthma cases (7/13, 53.8% each). While homozygous wild and mutant seemed to be protective and associated with mild disease in both alleles. Finally, 75% of Arg16Gly heterozygous group were good responders (P < 0.01), 81% of homozygous G mutant were bad responders. For Gln27Glu polymorphism, 60% of C wild group were good responders and 75% of G mutant group were bad responders.

CONCLUSIONS

The findings suggest that the Arg16Gly and Gln27Glu polymorphisms in the β2-AR gene are associated with asthma severity and response to therapy and might be used in personalized treatment for these patients in the future. This work is registered in ClinicalTrial.gov with ID: NCT03118869.

Beta-2 adrenergic receptor (ADRB2) gene polymorphisms and the risk of asthma: a meta-analysis of case-control studies

BACKGROUND AND OBJECTIVE

A number of studies have assessed the relationship between beta-2 adrenergic receptor (ADRB2) gene polymorphisms and asthma risk. However, the results are inconsistent. A meta-analysis that focused on the association between asthma and all ADRB2 polymorphisms with at least three case-control studies was thus performed.

METHODS

A literature search of the PubMed, Embase, Web of Science, CNKI, and Wangfang databases was conducted. Odds ratios with 95% confidence intervals were used to assess the strength of associations.

RESULTS

Arg16Gly, Gln27Glu, Thr164Ile, and Arg19Cys single nucleotide polymorphisms (SNPs) were identified in 46 case-control studies. The results showed that not all of the SNPs were associated with asthma in the overall population. Significant associations were found for the Arg16Gly polymorphism in the South American population via dominant model comparison (OR = 1.754, 95% CI = 1.179-2.609, I2 = 16.9%, studies  = 2, case  = 314, control  = 237) in an analysis stratified by ethnicity. For the Gln27Glu polymorphism, a protective association was found in children via recessive model comparison (OR = 0.566, 95% CI = 0.417-0.769, I2 = 0.0%, studies  = 11, case  = 1693, control  =  502) and homozygote genotype comparison (OR = 0.610, 95% CI = 0.434-0.856, I2 = 0.0%, studies  = 11, case  = 1693, control  = 1502), and in adults via dominant model comparison (OR = 0.864, 95% CI = 0.768-0.971, I2 = 46.9%, n = 18, case  = 3160, control  = 3433).

CONCLUSIONS

None of the ADRB2 gene polymorphisms were reproducibly associated with a risk of asthma across ethnic groups in the general population.

Association between β2-adrenoceptor gene polymorphisms and asthma risk: an updated meta-analysis

Background

Evidence is increasingly accumulated about multiple roles for the β2-adrenoceptor gene in asthma. The results were inconsistent partly due to small sample sizes. To assess the association between β2-adrenoceptor gene polymorphisms and asthma risk, a meta-analysis was performed.

Methods

We comprehensively searched the PubMed, EMBASE, BIOSIS Previews databases and extracted data from all eligible articles to estimate the association between β2-adrenoceptor gene polymorphisms and asthma risk. The pooled odds ratio (OR) with 95% confidence intervals (CIs) were calculated.

Results

Thirty-seven studies involving 6648 asthma patients and 15943 controls were included in the meta-analysis. Overall, significant associations were found in allelic genetic model (OR = 1.06, 95% CI = 1.01∼1.12), recessive genetic model (OR = 1.11, 95% CI = 1.02∼1.21) for Arg/Gly16. Stratified by ethnicity and age, significant associations were also found in Asian population in allelic genetic model, recessive genetic model and addictive model. For Gln/Glu27, no significant association was found when we combined all eligible studies. Age stratification showed significant associations in adults in allelic genetic model and recessive genetic model, but no significant association was found among Asians and Caucasians in ethnicity stratification.

Conclusions

This meta-analysis implied that the β2-adrenoceptor Arg/Gly16 polymorphism was likely to contribute to asthma risk in Asian population. Gln/Glu27 polymorphism might be a contributor to asthma susceptibility for adults.

Asthma susceptible genes in Chinese population: a meta-analysis

BACKGROUND

Published data regarding the associations between genetic variants and asthma risk in Chinese population were inconclusive. The aim of this study was to investigate asthma susceptible genes in Chinese population.

METHODS

The authors conducted 18 meta-analyzes for 18 polymorphisms in 13 genes from eighty-two publications.

RESULTS

Seven polymorphisms were found being associated with risk of asthma, namely: A Disintegrin and Metalloprotease 33 (ADAM33) T1-C/T (odds ratio [OR] = 6.07, 95% confidence interval [CI]: 2.69-13.73), Angiotensin-Converting Enzyme (ACE) D/I (OR = 3.85, 95%CI: 2.49-5.94), High-affinity IgE receptor β chain (FcεRIβ) -6843G/A (OR = 1.49, 95%CI: 1.01-2.22), Interleukin 13(IL-13) -1923C/T (OR = 2.99, 95%CI: 2.12-4.24), IL-13 -2044A/G (OR = 1.49, 95%CI: 1.07-2.08), Regulated upon Activation, Normal T cell Expressed and Secreted (RANTES) -28C/G (OR = 1.64, 95%CI: 1.09-2.46), Tumor Necrosis Factor-α (TNF-α) -308G/A(OR = 1.42, 95%CI: 1.09, 1.85). After subgroup analysis by age, the ACE D/I, β2-Adrenergic Receptor (β2-AR) -79G/C, TNF-α -308G/A, Interleukin 4 receptor(IL-4R) -1902G/A and IL-13 -1923C/T polymorphisms were found significantly associated with asthma risk in Chinese children. In addition, the ACE D/I, FcεRIβ -6843G/A, TNF-α -308G/A, IL-13 -1923C/T and IL-13 -2044A/G polymorphisms were associated with asthma risk in Chinese adults.

CONCLUSION

ADAM33, FcεRIβ, RANTES, TNF-α, ACE, β2-AR, IL-4R and IL-13 genes could be proposed as asthma susceptible genes in Chinese population. Given the limited number of studies, more data are required to validate these associations.

Beta2-adrenoceptor polymorphisms and asthma from childhood to middle age in the British 1958 birth cohort: a genetic association study

BACKGROUND

Functionally relevant polymorphisms of the beta2-adrenoceptor gene (ADRB2) are common in white populations, but their contribution to the burden of airways disease in the population is uncertain. We aimed to relate the long-term prevalence of asthma or wheeze to functional coding region polymorphisms in the ADRB2 gene.

METHODS

The British 1958 birth cohort consisted of all people born in Britain during a week in 1958. Asthma, wheezy bronchitis, and wheezing were ascertained by interview at ages 7, 11, 16, 23, 33, and 42 years, and lung function tests at 35 and 45 years. DNA samples from 8018 participants in the 45-year follow-up were genotyped for three coding variants in the ADRB2 gene. We extend the follow-up of this nationwide cohort by a further 10 years and relate asthma prevalence, prognosis, and lung function to functional coding region polymorphisms in the ADRB2 gene in the cohort members who contributed DNA samples. We also compared and combined our findings with those reaching significance in two previous meta-analyses.

FINDINGS

Half the cohort (4105 of 8018) had some history of wheezing illness by age 42 years. Neither lifetime prevalence nor age at onset were related to ADRB2 coding variants. However, the common polymorphisms Arg16Gly (rs1042713, Arg 16 allele frequency 36.3%) and Gln27Glu (rs1042714, Glu 27 allele frequency 44.6%) were significantly associated with persistence of asthmatic symptoms from childhood to middle age. Among homozygotes for the Arg16-Gln27 haplotype at these loci, 19.3% (41 of 212) childhood wheezers had five or more wheezing episodes in the past year at age 42, compared with 11.9% (71 of 599) with no copy of this haplotype. However, only 3% of all frequent adult wheezing was statistically attributable to this haplotype. The less common Thr164Ile polymorphism (rs1800888, Ile allele frequency 1.5%) was not a major predictor of either frequency or prognosis of asthma. Our data do not support the findings of previous meta-analyses when considered in isolation or when combined with their contributory studies.

INTERPRETATION

ADRB2 polymorphisms might predict a small component of the long-term prognosis in childhood asthma, but are not important determinants of asthma incidence or prevalence in the British population.

The C523A beta2 adrenergic receptor polymorphism associates with markers of asthma severity in African Americans

Our goal was to explore associations between ss2 adrenergic receptor polymorphisms and markers of asthma severity in African American and Caucasian patients with asthma. Polymorphisms at loci -1023, -654, -47, 46, 79, 491, and 523 were genotyped and haplotypes were imputed in 143 African Americans and 336 Caucasians. C523A genotype associated with percentage of African Americans (but not of Caucasians) having an asthma exacerbation: AA, AC, and CC genotypes were 17, 29, and 40%, respectively (p = 0.018). Symptom scores, pulmonary function, and rescue inhaler use paralleled exacerbation prevalence. We conclude the 523 A allele modifies asthma severity in African Americans.

The significance of beta2-adrenergic receptor polymorphisms in asthma

PURPOSE OF REVIEW

The gene that encodes the beta2-adrenergic receptor (ADRB2) is one of the most studied candidate genes in asthma. This review examines recent articles of the relationship between ADRB2 polymorphisms and asthma.

RECENT FINDINGS

Candidate gene association studies of ADRB2 and asthma have been dominated by analyses of the two common non-synonymous coding single nucleotide polymorphisms, Arg16Gly and Glu27Gly. Published studies have yielded inconsistent results. Three recent meta-analyses on the effects of these two polymorphisms have found no associations with asthma, although there were suggestions of associations with other asthma-related phenotypes, such as nocturnal asthma and asthma severity. Other recent studies have investigated other single nucleotide polymorphisms in this gene (i.e. single nucleotide polymorphisms in the promoter region and other single nucleotide polymorphisms in the coding region). These analyses have investigated the association between these single nucleotide polymorphisms (and haplotypes of these polymorphisms) and asthma-related phenotypes such as lung function, airways hyperresponsiveness, and response to a bronchodilator, and have suggested that certain regions of the gene may be associated with different phenotypes. Results from these studies, however, have also been inconsistent.

SUMMARY

Polymorphisms of ADRB2 are not major risk factors for the development of asthma. These polymorphisms are likely to be important, however, in determining drug response. Future studies need to fully characterize all of the variation in the gene and perform comprehensive association studies. Finally, interactions between ADRB2 and other genes in the beta-agonist pathway are an important and active area of research that will shed more light on inter-individual differences in drug response.

Systematic review and meta-analysis of the association between {beta}2-adrenoceptor polymorphisms and asthma: a HuGE review

A number of studies have investigated two common polymorphisms in the beta(2)-adrenoceptor gene, Arg/Gly16 and Gln/Glu27, in relation to asthma susceptibility. The authors performed a meta-analysis of each polymorphism, as well as haplotype analysis, for adult and pediatric populations separately, using published data, supplemented by additional data requested from the original authors. Individual analysis detected no effect of Arg/Gly16 in adults but did suggest a recessive protective effect of Gly16 for children, with an odds ratio of 0.71 (95% confidence interval (CI): 0.53, 0.96) compared with the other genotypes. Results for Gln/Glu27 in adults seem to indicate that heterozygotes are at decreased risk of asthma than either homozygote (odds ratio = 0.73, 95% CI: 0.62, 0.87), although the studies are heterogeneous; in children, the Glu/Glu genotype has a decreased risk of asthma (odds ratio = 0.60, 95% CI: 0.35, 0.99) compared with the other genotypes. Despite the proximity of these two polymorphic sites, the linkage disequilibrium coefficient of 0.41 was not high (p < 0.001). Haplotype analysis suggests that there may be an interaction between the two sites, with a lower risk of asthma associated with the Glu27 allele (compared with Gln27), and that this risk is modified by the allele at position 16.