Abstract
Aim: We studied the relative influence of genetic and environmental factors on the variation in susceptibility to atopic dermatitis and conducted a systematic review of the related literature.
Methods: In a population-based questionnaire study of 19,748 child and adolescent twins from the Danish Twin Registry, we calculated concordance rates and heritability of atopic dermatitis. We performed a systematic review of the literature to obtain thorough estimates of the heritability of the disease.
Results: The overall prevalence of atopic dermatitis in the population was 17.8% among girls and 14.7% among boys, p<0.001. The concordance rate for atopic dermatitis was significantly higher in monozygotic than in dizygotic twins; 0.80 vs. 0.41 among girls and 0.74 vs. 0.37 among boys. The overall heritability of atopic dermatitis was the same in boys and girls; 93% (90-94%) with the remainder of the phenotypic variance ascribable to non-shared environmental factors.
Conclusions: Atopic dermatitis is a highly heritable disorder. Compared with estimates from systematically identified studies the heritability of atopic dermatitis in the Danish population is substantial.
- © 2011 ERS