title: Atopic diseases by filaggrin mutations and birth year.
abstract: BACKGROUND
  The prevalence of atopic disorders has increased in recent years. The pathogenesis is complex with genetic and environmental risk factors. Filaggrin loss-of-function mutations are common and associated with atopic disorders. We investigated whether the prevalence of filaggrin mutations increased in different birth cohorts in adults from the general population in Denmark.
  
  
  METHODS
  Cross-sectional questionnaire and filaggrin gene mutation (R501X and 2282del4) data from 3335 18- to 69-year-old adults were available for analyses.
  
  
  RESULTS
  The effect of filaggrin mutations on the prevalence of atopic diseases, albeit not statistically significant, depended mostly on birth year for atopic dermatitis (AD). A nonsignificant increase in the prevalence of filaggrin mutations was noted across birth year groups reporting AD, with 12.9% in adults born in 1936-1949 and 19.0% born in 1976-1988.
  
  
  CONCLUSIONS
  If confirmed in other populations, the observed increase suggests that mutation carriers have been more susceptible to environmental changes accentuating the rise in AD prevalence.
authors.affiliation: National Allergy Research Centre, Department of Dermato-Allergology, Copenhagen University Hospital Gentofte, Hellerup, Denmark. jacpth01@geh.regionh.dk
authors.forename: J P
authors.initials: JP
authors.lastname: Thyssen
authors.forename: A
authors.initials: A
authors.lastname: Linneberg
authors.forename: J D
authors.initials: JD
authors.lastname: Johansen
authors.forename: B C
authors.initials: BC
authors.lastname: Carlsen
authors.forename: C
authors.initials: C
authors.lastname: Zachariae
authors.forename: M
authors.initials: M
authors.lastname: Meldgaard
authors.forename: P B
authors.initials: PB
authors.lastname: Szecsi
authors.forename: S
authors.initials: S
authors.lastname: Stender
authors.forename: T
authors.initials: T
authors.lastname: Menné
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D003430:Cross-Sectional Studies; D003718:Denmark / Q000453:epidemiology; D004777:Environment; D005260:Female; D000091344:Filaggrin Proteins; D059647:Gene-Environment Interaction; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000453:epidemiology / Q000235:genetics* / Q000276:immunology; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D007381:Intermediate Filament Proteins / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D015995:Prevalence; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D007381:Intermediate Filament Proteins; D007073:Immunoglobulin E