Three novel mutations in the glycoprotein IIb gene in a patient with type II Glanzmann thrombasthenia

Haematologica. 2007 May;92(5):698-701. doi: 10.3324/haematol.10847.

Abstract

In the platelets of a type II Glanzmann thrombasthenia patient, the amount of glycoprotein (GP) IIb and IIIa was significantly reduced. Three novel mutations were identified in the GPIIb gene (c.440C->G/p.Leu116Val, c.1772_1773insG/p.Asp560GlyfsX16 and c.2438C->A/p.His782Asn). p.Leu116Val did not represent a causative mutation. The c.1772_1773insG mutation resulted in an early stop codon and non-sense mediated decay of mRNA. When expressed in transfected BHK cells, the truncated protein was unable to form complex with GPIIIa. The p.His782Asn mutation compromised transport of the pro-GPIIb/IIIa complex from the endoplasmic reticulum to the Golgi, hindering its maturation and surface expression.

Publication types

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

MeSH terms

  • Animals
  • Cell Line
  • Codon, Nonsense
  • Cricetinae
  • DNA Mutational Analysis
  • Endoplasmic Reticulum / metabolism
  • Fibrinogen / metabolism
  • Genotype
  • Golgi Apparatus / metabolism
  • Humans
  • Integrin alpha2 / chemistry
  • Integrin alpha2 / genetics*
  • Integrin beta3 / metabolism
  • Male
  • Mesocricetus
  • Middle Aged
  • Protein Binding
  • Protein Interaction Mapping
  • Protein Processing, Post-Translational / genetics
  • Protein Structure, Tertiary
  • Protein Transport / genetics
  • Recombinant Fusion Proteins / metabolism
  • Structure-Activity Relationship
  • Thrombasthenia / genetics*
  • Transfection

Substances

  • Codon, Nonsense
  • ITGA2B protein, human
  • ITGB3 protein, human
  • Integrin alpha2
  • Integrin beta3
  • Recombinant Fusion Proteins
  • Fibrinogen