A mutation in the saposin A coding region of the prosaposin gene in an infant presenting as Krabbe disease: first report of saposin A deficiency in humans

Mol Genet Metab. 2005 Feb;84(2):160-6. doi: 10.1016/j.ymgme.2004.10.004.

Abstract

A six-month-old infant girl presenting with progressive encephalopathy and abnormal myelination in the cerebral white matter was originally diagnosed as suffering from Krabbe disease. The diagnosis was based on a deficiency of galactocerebrosidase activity found in leukocytes isolated from whole blood. When cultured skin fibroblasts did not show a similar enzyme deficiency and sulphatide (stearoyl-1-14C) uptake indicated an abnormal storage of galactosylceramide, a deficiency of an activator was implied. A three base pair deletion was found in the saposin A coding sequence of the prosaposin gene leading to the deletion of a conserved valine at amino acid number 11 of the saposin A protein. This deletion in saposin A is proposed as the cause for the abnormal galactosylceramide metabolism in this infant. This is the first report of a saposin A mutation in humans leading to pathological consequences.

Publication types

  • Case Reports

MeSH terms

  • Amniocentesis
  • Base Sequence
  • DNA Primers
  • Female
  • Galactosylceramidase / metabolism
  • Humans
  • Infant
  • Leukodystrophy, Globoid Cell / enzymology
  • Leukodystrophy, Globoid Cell / genetics*
  • Leukodystrophy, Globoid Cell / pathology
  • Magnetic Resonance Imaging
  • Mutation*
  • Polymerase Chain Reaction
  • Pregnancy
  • Saposins / genetics*

Substances

  • DNA Primers
  • Saposins
  • Galactosylceramidase