Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil.
J Bras Pneumol. 2009 Dec;35(12):1220-6. doi: 10.1590/s1806-37132009001200010.
Various wheezing phenotypes can be identified based on differences in natural histories, risk factors and responses to treatment. In epidemiologic studies, atopic asthma or virus-induced wheezing can be discriminated by the presence or the absence of sensitization to allergens. Children with asthma have been shown to present lower levels of lung function. Patients with viral respiratory infections evolve from normal lung function to enhanced airway reactivity. The objective of this study was to identify genes and polymorphisms associated with different wheezing phenotypes. Using data obtained from the Genetic Association Database, we systematically reviewed studies on genes and polymorphisms that have been associated with virus-induced wheezing or atopic asthma. The research was carried out in February of 2009. Genes associated with the studied outcomes in more than three studies were included in the analysis. We found that different genes and loci have been associated with virus-induced wheezing or atopic asthma. Virus-induced wheezing has frequently been associated with IL-8 polymorphisms, whereas atopic asthma and atopy have frequently been associated with Th2 cytokine gene (CD14 and IL-13) polymorphisms on chromosome 5. This review provides evidence that different wheezing disorders in childhood can be differently affected by genetic variations, considering their role on airway inflammation and atopy. Future studies of genetic associations should consider the different wheezing phenotypes in infancy. In addition, stratified analyses for atopy can be useful for elucidating the mechanisms of the disease.
根据自然病史、危险因素和治疗反应的差异，可以确定各种喘息表型。在流行病学研究中，通过过敏原致敏的存在与否，可以区分特应性哮喘或病毒诱导的喘息。已经表明哮喘儿童的肺功能水平较低。患有病毒性呼吸道感染的患者会从正常的肺功能发展为增强的气道反应性。本研究的目的是确定与不同喘息表型相关的基因和多态性。我们使用来自遗传关联数据库的数据，系统地回顾了与病毒诱导的喘息或特应性哮喘相关的基因和多态性研究。研究于 2009 年 2 月进行。纳入了在三项以上研究中与研究结果相关的基因和多态性进行分析。我们发现，不同的基因和基因座与病毒诱导的喘息或特应性哮喘有关。病毒诱导的喘息常与 IL-8 多态性有关，而特应性哮喘和特应性常与染色体 5 上的 Th2 细胞因子基因（CD14 和 IL-13）多态性有关。这篇综述提供了证据表明，不同的儿童喘息障碍可能受到遗传变异的不同影响，考虑到它们在气道炎症和特应性中的作用。未来的遗传关联研究应考虑婴儿期的不同喘息表型。此外，对特应性的分层分析可能有助于阐明疾病的机制。
