title: Establishing a birth cohort to investigate the course and aetiology of asthma and allergies across three generations - rationale, design, and methods of the ACROSSOLAR study.
abstract: BACKGROUND
  Atopic diseases are a major burden of disease on a global scale. Regarding their aetiology, the early years of life are assumed to play a crucial role. In addition, there is growing evidence that elucidating the impact of cross-generational effects and epigenetic mechanisms such as DNA methylation can substantially widen the scientific knowledge of the occurrence and progression of these diseases. We are thus aiming at following the course of asthma, allergies, and potential risk factors for their occurrence across three generations by establishing a birth cohort in the offspring of an existing population-based cohort.
  
  
  METHODS
  2051 young adults who have been recruited in 1995 for Phase II of the International Study of Asthma and Allergies in Childhood (ISAAC) and who have subsequently been followed-up by the Study on Occupational Allergy Risks (SOLAR) are asked bi-annually since 2009 if they conceived a child in the meantime. If parenthood is reported, parents are invited to enrol along with their children in the ACROSSOLAR cohort. Participation involves completing a questionnaire assessing general and health-related information about the course of the pregnancy and the first year of life of their children. Subsequently, the children are followed up until primary school age when asthma and allergies can be diagnosed reliably. In addition, DNA for epigenetic analysis will be collected and analysed. Longitudinal data analysis techniques will then be used to assess potential associations between early-life exposures and onset of childhood asthma and allergies taking into account epigenetics.
  
  
  CONCLUSIONS
  Birth cohorts are especially suited to elucidate the impact of genetic predisposition, epigenetics, exposures during the first years of life, and gene-environment interactions on the occurrence and progression of asthma and allergies. By building upon an existing cohort, ACROSSOLAR offers a unique and cost-effective opportunity to investigate the aetiology of atopic disease in a prospective and cross-generational way.
authors.affiliation: Occupational and Environmental Epidemiology & NetTeaching Unit, Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, University Hospital of Munich (LMU), Ziemssenstr. 1, 80336, Munich, Germany. tobias.weinmann@med.lmu.de.|German Centre for Lung Research (DZL), Munich, Germany. tobias.weinmann@med.lmu.de.
authors.forename: Tobias
authors.initials: T
authors.lastname: Weinmann
authors.affiliation: Occupational and Environmental Epidemiology & NetTeaching Unit, Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, University Hospital of Munich (LMU), Ziemssenstr. 1, 80336, Munich, Germany. jessica.gerlich@med.lmu.de.|German Centre for Lung Research (DZL), Munich, Germany. jessica.gerlich@med.lmu.de.
authors.forename: Jessica
authors.initials: J
authors.lastname: Gerlich
authors.affiliation: Occupational and Environmental Epidemiology & NetTeaching Unit, Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, University Hospital of Munich (LMU), Ziemssenstr. 1, 80336, Munich, Germany. sabine.heinrich@med.lmu.de.|German Centre for Lung Research (DZL), Munich, Germany. sabine.heinrich@med.lmu.de.
authors.forename: Sabine
authors.initials: S
authors.lastname: Heinrich
authors.affiliation: Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, University Hospital of Munich (LMU), Ziemssenstr. 1, 80336, Munich, Germany. dennis.nowak@med.lmu.de.|German Centre for Lung Research (DZL), Munich, Germany. dennis.nowak@med.lmu.de.
authors.forename: Dennis
authors.initials: D
authors.lastname: Nowak
authors.affiliation: Occupational and Environmental Epidemiology & NetTeaching Unit, Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, University Hospital of Munich (LMU), Ziemssenstr. 1, 80336, Munich, Germany. jenny.gerdes@gmail.com.|German Centre for Lung Research (DZL), Munich, Germany. jenny.gerdes@gmail.com.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Gerdes
authors.affiliation: Occupational and Environmental Epidemiology & NetTeaching Unit, Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, University Hospital of Munich (LMU), Ziemssenstr. 1, 80336, Munich, Germany. jenny.schlichtiger@med.lmu.de.|German Centre for Lung Research (DZL), Munich, Germany. jenny.schlichtiger@med.lmu.de.
authors.forename: Jenny
authors.initials: J
authors.lastname: Schlichtiger
authors.affiliation: Dr. v. Haunersches Kinderspital, University Hospital of Munich (LMU), Lindwurmstr. 4, 80337, Munich, Germany. erika.von.mutius@med.lmu.de.|German Centre for Lung Research (DZL), Munich, Germany. erika.von.mutius@med.lmu.de.
authors.forename: Erika
authors.initials: E
authors.lastname: von Mutius
authors.affiliation: Dr. v. Haunersches Kinderspital, University Hospital of Munich (LMU), Lindwurmstr. 4, 80337, Munich, Germany. bianca.schaub@med.lmu.de.|German Centre for Lung Research (DZL), Munich, Germany. bianca.schaub@med.lmu.de.
authors.forename: Bianca
authors.initials: B
authors.lastname: Schaub
authors.affiliation: Paediatric Department, University Hospital Carl Gustav Carus Dresden, TU Dresden, Fetscherstr. 74, 01307, Dresden, Germany. christian.vogelberg@uniklinikum-dresden.de.
authors.forename: Christian
authors.initials: C
authors.lastname: Vogelberg
authors.affiliation: Paediatric Department, University Hospital Carl Gustav Carus Dresden, TU Dresden, Fetscherstr. 74, 01307, Dresden, Germany. diana.roller@uniklinikum-dresden.de.
authors.forename: Diana
authors.initials: D
authors.lastname: Roller
authors.affiliation: Occupational and Environmental Epidemiology & NetTeaching Unit, Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, University Hospital of Munich (LMU), Ziemssenstr. 1, 80336, Munich, Germany. sekretariat-radon@med.lmu.de.|German Centre for Lung Research (DZL), Munich, Germany. sekretariat-radon@med.lmu.de.
authors.forename: Katja
authors.initials: K
authors.lastname: Radon
mesh_terms: D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000209:etiology* / Q000235:genetics; D002648:Child; D004777:Environment; D044127:Epigenesis, Genetic; D005191:Family Characteristics; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D006967:Hypersensitivity / Q000209:etiology* / Q000235:genetics; D008297:Male; D018579:Patient Selection; D011247:Pregnancy; D011446:Prospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires; D055815:Young Adult