title: New mutation identified in two sisters with adult-onset erythropoietic protoporphyria.
abstract: BACKGROUND
  Erythropoietic protoporphyria (EPP; OMIM #177000) is a rare disease that usually presents in infancy or early childhood. The uncommon adult-onset EPP is often associated with acquired somatic mutations of the FECH gene, secondary to blood dyscracias.
  
  
  METHODS
  We investigated two sisters with adult-onset EPP.
  
  
  RESULTS
  We found a novel germline mutation in the FECH gene, in trans with the common hypomorphic IVS3-48C allele.
  
  
  CONCLUSIONS
  The adult presentation and identical genotypes of the two sisters suggests that the late development of the condition is to an extent a function of the mutation. The exact mechanism for this delayed penetrance is not clear, although these atypical cases raise the possibility of other genetic or nongenetic disease-modifying factors.
authors.affiliation: Department of Dermatology, The James Cook University Hospital, Middlesbrough, UK. jaskiran.azad@stees.nhs.uk
authors.forename: J
authors.initials: J
authors.lastname: Azad
authors.forename: P
authors.initials: P
authors.lastname: Brennan
authors.forename: A J
authors.initials: AJ
authors.lastname: Carmichael
mesh_terms: D000328:Adult; D017668:Age of Onset; D005091:Exons / Q000235:genetics; D005260:Female; D005294:Ferrochelatase / Q000235:genetics*; D006801:Humans; D020125:Mutation, Missense; D046351:Protoporphyria, Erythropoietic / Q000235:genetics*; D017422:Sequence Analysis, DNA; D035781:Siblings
chemical_list: D005294:Ferrochelatase