title: Hereditary amyloidosis in early childhood associated with a novel insertion-deletion (indel) in the fibrinogen Aalpha chain gene.
abstract: BACKGROUND
  Systemic amyloidosis occurring in early childhood is extremely rare, and is usually of AA type complicating chronic inflammatory diseases. We report the molecular basis of amyloidosis in a Korean girl who presented at 7 years of age with asymptomatic proteinuria and developed amyloid hepatomegaly and end-stage renal failure within 2 years.
  
  
  METHODS
  Renal biopsy showed enlarged glomeruli virtually replaced by amyloid, but without interstitial or vascular involvement. The histologic appearance was identical to that seen in patients with hereditary fibrinogen Aalpha chain Glu526Val amyloidosis, and the amyloid deposits stained specifically with antibodies to fibrinogen. Mutations were sought in the genes of the amyloidogenic proteins, transthyretin, apolipoprotein AI, lysozyme and fibrinogen Aalpha chain genes by polymerase chain reaction (PCR) and sequencing.
  
  
  RESULTS
  A unique frameshift insertion-deletion (indel) mutation was identified in one allele of her fibrinogen Aalpha chain gene, which encodes a partly novel peptide and a premature stop signal, similar to the two previously reported amyloidogenic point deletions at codons 522 and 524 in this molecule. The mutation was absent in samples verified to be from her parents, indicating that it had occurred de novo.
  
  
  CONCLUSIONS
  This is the first description of hereditary fibrinogen Aalpha chain amyloidosis in an Asian individual, and the distinctive renal histology offered a strong clue to the diagnosis. The disease is potentially curable by combined hepatorenal transplantation.
authors.affiliation: Department of Pediatrics, Seoul National University Medical School, Clinical Research Institute, Seoul National University Hospital, Seoul, Korea.
authors.forename: Hee Gyung
authors.initials: HG
authors.lastname: Kang
authors.forename: Alison
authors.initials: A
authors.lastname: Bybee
authors.forename: Il Soo
authors.initials: IS
authors.lastname: Ha
authors.forename: Moon Soo
authors.initials: MS
authors.lastname: Park
authors.forename: Janet A
authors.initials: JA
authors.lastname: Gilbertson
authors.forename: Hae Il
authors.initials: HI
authors.lastname: Cheong
authors.forename: Yong
authors.initials: Y
authors.lastname: Choi
authors.forename: Philip N
authors.initials: PN
authors.lastname: Hawkins
mesh_terms: D000595:Amino Acid Sequence; D028226:Amyloidosis, Familial / Q000235:genetics* / Q000473:pathology; D044466:Asian People / Q000235:genetics; D001483:Base Sequence; D002648:Child; D005260:Female; D005340:Fibrinogen / Q000235:genetics*; D016368:Frameshift Mutation; D017353:Gene Deletion; D006801:Humans; D007723:Korea; D008969:Molecular Sequence Data
chemical_list: C464794:fibrinogen Aalpha; D005340:Fibrinogen