RT Journal Article
SR Electronic
T1 Childhood asthma and hay fever are heritable, but specific high-risk genetic variants are not shared between diseases
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP OA1469
DO 10.1183/13993003.congress-2015.OA1469
VO 46
IS suppl 59
A1 Vilhelmina Ullemar
A1 Patrik Magnusson
A1 Cecilia Lundholm
A1 Anna Zettergren
A1 Erik Melén
A1 Paul Lichtenstein
A1 Catarina Almqvist
YR 2015
UL http://erj.ersjournals.com/content/46/suppl_59/OA1469.abstract
AB Introduction: Genetic factors in asthma have been studied using both quantitative and molecular genetics. These methods agree there is a strong genetic component, but quantitative genetic studies in children are few. While comorbidity is well-known between asthma and hay fever, the heritability of hay fever and shared genetic variants with asthma are less studied.Aims and Objectives: We aimed to estimate the heritability of asthma and hay fever in twins, and to compare the results to a molecular genetic study within the same population.Methods: The study population included 25,306 twins 9-12 years old from the Child and Adolescent Twin Study in Sweden. Childhood asthma and hay fever were assessed based on questionnaire data. For asthma information from national health registers was also used. From disease correlations in monozygotic and dizygotic twin pairs, heritability was estimated with 95%CI. For the molecular genetic analysis 16 single nucleotide polymorphisms (SNP:s) with previously shown strong association to childhood asthma were selected. A subset of 10,075 twins was genotyped.Results: Both childhood asthma and hay fever had ∼80% heritability: for childhood asthma it was 0.82 (95% CI 0.79-0.85), for hay fever 0.78 (95% CI 0.73-0.82). Of the 16 SNP:s, six were significantly associated with asthma. Only one of the SNP:s (rs3771180 in IL1RL1) was significantly associated with both asthma (OR 0.76, 95% CI 0.68-0.86, p=1.0*10-5) and hay fever (OR 0.64, 95% CI 0.53-0.77, p=2.5*10-6).Conclusion: While childhood asthma and hay fever are both highly heritable, high-risk genetic variants associated with asthma were typically not shared between these diseases.