title: Filaggrin genotype and skin diseases independent of atopic dermatitis in childhood.
abstract: BACKGROUND
  Filaggrin gene (FLG) mutations compromise skin barrier functions and increase risk of atopic dermatitis. We aimed to study effects on other skin diseases using unique data from the Danish registers.
  
  
  METHODS
  FLG genotyping of a population-based sample of 1547 children with extracted DNA and information on skin diseases from the Danish National Birth Cohort and Health Register, with 18 years follow-up during years 1996-2013. Odds ratios (OR) and hazard ratios (HR) were estimated using logistic regression and Cox regression, respectively, and adjusted for physician-diagnosed atopic dermatitis.
  
  
  RESULTS
  FLG mutations were associated with increased risk of dry skin (OR 1.9, CI 1.1-3.1), and a decreased risk of fungal skin infections at age <18 months (OR 0.2, CI 0.1-0.8). There was no association with wart treatments (HR 1.0, CI 0.6-1.7). FLG mutations were associated with an increased risk of atopic dermatitis (OR 3.3, CI 2.1-5.3), dermatology consultations for allergy or rash (HR 2.2, CI 1.4-3.5), basic dermatology consultations at age <5 years (HR 2.2, CI 1.7-2.9), urticaria at age <18 months (OR 2.9, CI 1.0-7.9), and other rash at age <18 months (OR 2.1, CI 1.2-3.8).
  
  
  CONCLUSIONS
  FLG mutations may predispose to skin disease in young children including urticaria, and rash not recognized as atopic dermatitis although equally frequent. In clinical practice, FLG genotyping may help indicate the use of moisturizers to reduce skin problems.
authors.affiliation: Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Bager
authors.affiliation: Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Jan
authors.initials: J
authors.lastname: Wohlfahrt
authors.affiliation: Department of Dermato-Allergology, National Allergy Research Centre, Copenhagen University Hospital Gentofte, Copenhagen, Denmark.
authors.forename: Jacob Pontoppidan
authors.initials: JP
authors.lastname: Thyssen
authors.affiliation: Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Mads
authors.initials: M
authors.lastname: Melbye
mesh_terms: D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004252:DNA Mutational Analysis; D003876:Dermatitis, Atopic / Q000235:genetics*; D005076:Exanthema / Q000235:genetics*; D005260:Female; D000091344:Filaggrin Proteins; D005500:Follow-Up Studies; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D007381:Intermediate Filament Proteins / Q000235:genetics*; D008297:Male; D009154:Mutation / Q000235:genetics*; D012042:Registries; D014581:Urticaria / Q000235:genetics*
chemical_list: C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D007381:Intermediate Filament Proteins
keywords: atopic dermatitis; dry skin; filaggrin; fungus; genotype; warts