Barnes Kathleen C
The Johns Hopkins Asthma and Allergy Center, Baltimore, MD 21224, USA.
J Allergy Clin Immunol. 2006 Feb;117(2):243-54; quiz 255-6. doi: 10.1016/j.jaci.2005.11.030.
The striking racial and ethnic disparities in disease prevalence for common disorders, such as allergic asthma, cannot be explained entirely by environmental, social, cultural, or economic factors, and genetic factors should not be ignored. Unfortunately, genetic studies in underserved minorities are hampered by disagreements over the biologic construct of race and logistic issues, including admixture of different races and ethnicities. Current observations suggest that the frequency of high-risk variants in candidate genes can differ between African Americans, Puerto Ricans, and Mexican Americans, and this might contribute to the differences in disease prevalence. Maintenance of certain allelic variants in the population over time might reflect selective pressures in previous generations. For example, significant associations between markers in certain candidate genes (eg, STAT6, ADRB2, and IFNGR1) for traits such as high total IgE levels observed in resistance to extracellular parasitic disease in one population and atopic asthma in another supports the common disease/common variant model for disease. Herein is a discussion of how genetic variants might explain, at least in part, the marked disparities observed in risk to allergic asthma.
常见疾病（如过敏性哮喘）在患病率方面存在显著的种族和民族差异，这不能完全由环境、社会、文化或经济因素来解释，遗传因素也不应被忽视。不幸的是，在医疗服务不足的少数群体中进行基因研究受到了种族生物学结构方面的分歧以及后勤问题的阻碍，这些问题包括不同种族和民族的混合。目前的观察表明，候选基因中高风险变异的频率在非裔美国人、波多黎各人以及墨西哥裔美国人之间可能存在差异，这可能导致疾病患病率的不同。随着时间的推移，某些等位基因变异在人群中的维持可能反映了前几代人的选择压力。例如，在一个人群中观察到某些候选基因（如STAT6、ADRB2和IFNGR1）中的标记与对细胞外寄生虫病的抵抗力等性状之间存在显著关联，而在另一个人群中这些标记与特应性哮喘之间存在显著关联，这支持了疾病的常见疾病/常见变异模型。本文将讨论基因变异如何至少部分地解释在过敏性哮喘风险中观察到的显著差异。
