Beta-spectrinBari: a truncated beta-chain responsible for dominant hereditary spherocytosis

Haematologica. 2009 Dec;94(12):1753-7. doi: 10.3324/haematol.2009.010124. Epub 2009 Jul 16.

Abstract

We describe a beta-spectrin variant, named beta-spectrin Bari, characterized by a truncated chain and associated with hereditary spherocytosis. The clinical phenotype consists of a moderately severe hemolytic anemia, splenomegaly, and spherocytes and acanthocytes in the blood smear. The occurrence of the truncated protein, that represents about 8% of the total beta-spectrin occurring on the membrane, results in a marked spectrin deficiency. The altered protein is due to a single point mutation at position -2 (A->G) of the acceptor splice site of intron 16 leading to an aberrant beta-spectrin message skipping exons 16 and 17 indistinguishable from that reported for beta-spectrin Winston-Salem. We provide evidence that the mutated gene is transcribed but its mRNA is less abundant than either its normal counterpart or beta-spectrin Winston-Salem mRNA. Our findings are an example of how mutations in different splice sites, although causing the same truncating effect, result in clearly different clinical pictures.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acanthocytes / pathology
  • Adult
  • Anemia, Hemolytic / pathology
  • Base Sequence
  • Blotting, Western
  • DNA Mutational Analysis
  • Family Health
  • Female
  • Humans
  • Male
  • Point Mutation*
  • RNA Splice Sites / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Spectrin / genetics*
  • Spectrin / metabolism
  • Spherocytes / pathology
  • Spherocytosis, Hereditary / blood
  • Spherocytosis, Hereditary / genetics*
  • Spherocytosis, Hereditary / pathology
  • Splenomegaly / pathology

Substances

  • RNA Splice Sites
  • Spectrin