Autosomal dominant thrombocytopenias with reduced expression of glycoprotein Ia.

We have recently studied a case series of 46 unrelated patients with inherited thrombocytopenias and identified 18 cases that did not fit any known platelet disorder. In two unrelated families, a mild thrombocytopenia with normal platelet size was transmitted in an autosomal dominant fashion. Bleeding time was prolonged in 5 investigated patients. In all of them, flow cytometry and SDS-PAGE of platelet glycoproteins (GP) showed a reduced content of GPIa, a subunit of the GPIa-IIa complex (also known as integrin alpha 2 beta(1)) that is a major collagen receptor on platelets. All other membrane GPs were within the normal range. GPIa deficiency was associated with severely reduced in vitro platelet adhesion to molecules known to interact selectively with GPIa. In vitro platelet aggregation was normal in all subjects, except for a suboptimal platelet response to fibrillar collagen in two patients. A mild defect of alpha-granules was observed in all affected subjects. No mutation was identified in the genes encoding for GPIa or GPIIa. Since no other similar cases have been reported in the literature, we suggest that an autosomal dominant thrombocytopenia associated with GPIa deficiency and alpha-granule defect represents a new form of inherited thrombocytopenia.
AuthorsPatrizia Noris, Gianni F Guidetti, Valeria Conti, Iride F Ceresa, Michele Di Pumpo, Alessandro Pecci, Mauro Torti, Anna Savoia, Carlo L Balduini
JournalThrombosis and haemostasis (Thromb Haemost) Vol. 95 Issue 3 Pg. 483-9 (Mar 2006) ISSN: 0340-6245 [Print] Germany
PMID16525577 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
Chemical References
  • Integrin alpha2
  • Thrombospondin 1
  • Collagen
  • Adult
  • Aged
  • Bleeding Time
  • Blood Platelets (drug effects, metabolism)
  • Collagen (pharmacology)
  • Female
  • Genes, Dominant
  • Hemostasis (genetics)
  • Humans
  • Integrin alpha2 (blood)
  • Male
  • Pedigree
  • Phenotype
  • Platelet Adhesiveness
  • Platelet Aggregation
  • Thrombocytopenia (blood, diagnosis, genetics)
  • Thrombospondin 1 (metabolism)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research network!

Choose Username:
Verify Password: