Epidermolysis bullosa simplex-generalized severe type due to keratin 5 p.Glu477Lys mutation: Genotype-phenotype correlation and in silico modeling analysis

Pediatr Dermatol. 2019 Jan;36(1):132-138. doi: 10.1111/pde.13722. Epub 2018 Dec 4.

Abstract

Background/objectives: Epidermolysis bullosa is a group of diseases caused by mutations in skin structural proteins. Availability of genetic sequencing makes identification of causative mutations easier, and genotype-phenotype description and correlation are important. We describe six patients with a keratin 5 mutation resulting in a glutamic acid to lysine substitution at position 477 (p.Glu477Lys) who have a distinctive, severe and sometimes fatal phenotype. We also perform in silico modeling to show protein structural changes resulting in instability.

Methods: In this case series, we collected clinical data from six patients with this mutation identified from their national or local epidermolysis bullosa databases. We performed in silico modeling of the keratin 5-keratin 14 coil 2B complex using CCBuilder and rendered with Pymol (Schrodinger, LLC, New York, NY).

Results: Features include aplasia cutis congenita, generalized blistering, palmoplantar keratoderma, onychodystrophy, airway and developmental abnormalities, and a distinctive reticulated skin pattern. Our in silico model of the keratin 5 p.Glu477Lys mutation predicts conformational change and modification of the surface charge of the keratin heterodimer, severely impairing filament stability.

Conclusions: Early recognition of the features of this genotype will improve care. In silico analysis of mutated keratin structures provides useful insights into structural instability.

Keywords: epidermolysis bullosa; genetic diseases/mechanisms; genodermatoses.

Publication types

  • Case Reports

MeSH terms

  • Child
  • Child, Preschool
  • Computer Simulation
  • Databases, Factual
  • Epidermolysis Bullosa Simplex / genetics*
  • Female
  • Genetic Association Studies
  • Genotype
  • Humans
  • Infant, Newborn
  • Keratin-5 / genetics*
  • Male
  • Mutation
  • Phenotype
  • Skin / pathology

Substances

  • KRT5 protein, human
  • Keratin-5

Associated data

  • GENBANK/NM_000424.3
  • GENBANK/NP_000415.2