Simultaneous deficiency of sphingolipid activator proteins 1 and 2 is caused by a mutation in the initiation codon of their common gene

J Biol Chem. 1992 Feb 15;267(5):3312-5.


Sphingolipid activator proteins (SAPs) are small, nonenzymic glycoproteins that stimulate lysosomal degradation of various sphingolipids. SAP-1, SAP-2, and two additional potential activator proteins are derived from a common precursor by proteolytic processing. A severe case of sphingolipid storage disease that led to death within 16 weeks was attributed to a possible total deficiency of the SAPs generated by this gene (Harzer, K., Paton, B. C., Poulos, A., Kustermann-Kuhn, B., Roggendorf, W., Grisar, T., and Popp, M. (1989) Eur. J. Pediatr. 149, 31-39). Analysis of the SAP precursor cDNA from the patient and his fetal sibling showed an A to T transversion in the initiation codon. Allele-specific oligonucleotide hybridization revealed that both parents are heterozygous carriers for this mutation. In pulse-chase experiments using antisera raised against SAP-1 or SAP-2, no cross-reacting material could be detected in the patients' fibroblasts.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alleles
  • Base Sequence
  • Cells, Cultured
  • Codon / genetics
  • Fibroblasts / metabolism
  • Glycoproteins / deficiency
  • Glycoproteins / genetics*
  • Humans
  • Lipid Metabolism, Inborn Errors / genetics*
  • Male
  • Molecular Sequence Data
  • Mutation*
  • Oligodeoxyribonucleotides
  • Polymerase Chain Reaction
  • RNA / genetics
  • RNA / isolation & purification
  • Saposins
  • Skin / metabolism
  • Sphingolipid Activator Proteins


  • Codon
  • Glycoproteins
  • Oligodeoxyribonucleotides
  • PSAP protein, human
  • Saposins
  • Sphingolipid Activator Proteins
  • RNA

Associated data

  • GENBANK/D12753
  • GENBANK/M81355
  • GENBANK/M84123
  • GENBANK/M84124
  • GENBANK/M84125
  • GENBANK/M84126
  • GENBANK/M84127
  • GENBANK/M84128
  • GENBANK/M84129
  • GENBANK/M84130