title: Compound heterozygotes for filaggrin gene mutations do not always show severe atopic dermatitis.
abstract: BACKGROUND
  Mutations in FLG, which encodes profilaggrin, cause ichthyosis vulgaris (IV) and are an important predisposing factor for atopic dermatitis (AD). IV shows autosomal hemidominant (semidominant) inheritance, and patients with bi-allelic FLG mutations tend to have severe IV phenotypes. However, the effect of bi-allelic FLG mutations on AD incidence and severity remains a subject of controversy.
  
  
  OBJECTIVE
  In this study, we studied individuals with bi-allelic null FLG mutations to elucidate the effect of bi-allelic FLG mutations on AD incidence and severity.
  
  
  METHODS
  Six individuals with bi-allelic FLG null mutations from three families of IV/AD were investigated. We report the detailed clinical features of the individuals. The phenotype was confirmed by the clinical examinations and the severity of IV and AD was scored using ichthyosis score and Eczema Area and Severity Index (EASI).
  
  
  RESULTS
  It was found that five of the six patients had severe IV, and the remaining patient showed moderate IV. Two of the six had moderate AD and three of the six had mild AD. The remaining patient had no AD.
  
  
  CONCLUSIONS
  Our results suggest that individuals with bi-allelic FLG mutations do not always have severe AD and confirm that not all individuals with bi-allelic FLG mutations have AD.
authors: Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors: A
authors: A
authors: Sekiya
authors: Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors: M
authors: M
authors: Kono
authors: Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors: H
authors: H
authors: Tsujiuchi
authors: Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors: T
authors: T
authors: Kobayashi
authors: Department of Dermatology, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors: T
authors: T
authors: Nomura
authors: Department of Dermatology, Showa University School of Medicine, Tokyo, Japan.
authors: M
authors: M
authors: Kitakawa
authors: Department of Dermatology, Toyohashi Municipal Hospital, Toyohashi, Japan.
authors: N
authors: N
authors: Suzuki
authors: Department of Dermatology, Mie University School of Medicine, Tsu, Japan.
authors: K
authors: K
authors: Yamanaka
authors: Department of Dermatology, Showa University School of Medicine, Tokyo, Japan.
authors: H
authors: H
authors: Sueki
authors: Centre for Dermatology and Genetic Medicine, College of Life Sciences and College of Medicine, Dentistry & Nursing, University of Dundee, Dundee, UK.
authors: W H I
authors: WH
authors: McLean
authors: Department of Dermatology, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors: H
authors: H
authors: Shimizu
authors: Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors: M
authors: M
authors: Akiyama
mesh_terms: D000328:Adult; D003876:Dermatitis, Atopic / Q000235:genetics*; D005260:Female; D000091344:Filaggrin Proteins; D006579:Heterozygote; D006801:Humans; D008297:Male; D009154:Mutation