Department of Respiratory Medicine, Bispebjerg Hospital, Copenhagen, Denmark.
Clin Exp Allergy. 2010 Jul;40(7):1054-61. doi: 10.1111/j.1365-2222.2010.03525.x. Epub 2010 May 26.
Asthma is a complex disease characterized by symptoms of wheezing, shortness of breath, chest tightness, and cough.
To study the relative contribution of genetic and environmental factors in the liability to asthma in a large sample of twins.
Data on asthma in 21,135 twin pairs, 3-71 years of age, from the Danish Twin Registry were collected via a multidisciplinary questionnaire survey. Heritability estimates were calculated using variance components models.
A monozygotic twin had an approximately sixfold increased risk of asthma whereas a dizygotic twin only had an approximately threefold increased risk relative to the general population if his or her co-twin was affected. The difference was more pronounced among males. Familial aggregation of asthma in children and adolescents was explained mainly by additive genetic factors, but common environment was also important. The heritability of asthma was also substantial in adults aged 20-49 years. In older adults (aged 50-71 years), additive genetic factors did not significantly influence the disease risk.
Genetic influences on asthma are substantial throughout the life span but the proportion of the disease liability explained by genetic factors is decreased in older adults.
哮喘是一种复杂的疾病，其特征是喘息、呼吸急促、胸闷和咳嗽等症状。
在大量双胞胎样本中研究遗传和环境因素对哮喘易感性的相对贡献。
通过多学科问卷调查收集了来自丹麦双胞胎登记处的 21,135 对年龄在 3-71 岁的双胞胎的哮喘数据。使用方差分量模型计算遗传率估计值。
同卵双胞胎患哮喘的风险大约增加了六倍，而异卵双胞胎如果其同卵双胞胎患病，则患哮喘的风险仅增加了大约三倍。这种差异在男性中更为明显。儿童和青少年哮喘的家族聚集主要归因于加性遗传因素，但共同环境也很重要。20-49 岁成年人的哮喘遗传率也很高。在年龄较大的成年人（50-71 岁）中，加性遗传因素对疾病风险没有显著影响。
遗传因素对哮喘的影响贯穿整个生命周期，但遗传因素对疾病易感性的解释比例在老年人中降低。
