Gray platelet syndrome

Gray platelet syndrome
Classification and external resources
Specialty hematology
ICD-10 D69.1
OMIM 139090
DiseasesDB 29160
MedlinePlus 000582

Gray platelet syndrome (GPS), or platelet alpha-granule deficiency,[1] is a rare congenital autosomal recessive bleeding disorder caused by a reduction or absence of alpha-granules in blood platelets, and the release of proteins normally contained in these granules into the marrow, causing myelofibrosis.[2]

GPS is primarily inherited in an autosomal recessive manner, and the gene that is mutated in GPS has recently been mapped to chromosome 3p[3] and identified as NBEAL2.[4] NBEAL2 encodes a protein containing a BEACH domain that is predicted to be involved in vesicular trafficking. It is expressed in platelets and megakaryocytes and is required for the development of platelet alpha-granules.[5] NBEAL2 expression is also required for the development of thrombocytes in zebrafish.[6]

GPS is characterized by "thrombocytopenia, and abnormally large agranular platelets in peripheral blood smears."[7] The defect in GPS is the failure of megakaryocytes to package secretory proteins into alpha-granules. Patients with the GPS are affected by mild to moderate bleeding tendencies.

See also


  1. Online Mendelian Inheritance in Man (OMIM) 139090
  2. Nurden AT, Nurden P (2007). "The gray platelet syndrome: clinical spectrum of the disease". Blood Rev. 21 (1): 21–36. doi:10.1016/j.blre.2005.12.003. PMID 16442192.
  3. Gunay-Aygun M, Zivony-Elboum Y, Gumruk F, et al. (December 2010). "Gray platelet syndrome: natural history of a large patient cohort and locus assignment to chromosome 3p". Blood. 116 (23): 4990–5001. doi:10.1182/blood-2010-05-286534. PMC 3012593Freely accessible. PMID 20709904.
  4. Kahr WH, Hinckley J, Li L, et al. (August 2011). "Mutations in NBEAL2, encoding a BEACH protein, cause gray platelet syndrome". Nat. Genet. 43 (8): 738–40. doi:10.1038/ng.884. PMID 21765413.
  5. Gunay-Aygun M, Falik-Zaccai TC, Vilboux T, et al. (August 2011). "NBEAL2 is mutated in gray platelet syndrome and is required for biogenesis of platelet α-granules". Nat. Genet. 43 (8): 732–4. doi:10.1038/ng.883. PMC 3154019Freely accessible. PMID 21765412.
  6. Albers CA, Cvejic A, Favier R, et al. (August 2011). "Exome sequencing identifies NBEAL2 as the causative gene for gray platelet syndrome". Nat. Genet. 43 (8): 735–7. doi:10.1038/ng.885. PMC 3428934Freely accessible. PMID 21765411.
  7. Jantunen E, Hänninen A, Naukkarinen A, Vornanen M, Lahtinen R (July 1994). "Gray platelet syndrome with splenomegaly and signs of extramedullary hematopoiesis: a case report with review of the literature". Am. J. Hematol. 46 (3): 218–24. doi:10.1002/ajh.2830460311. PMID 8192152.

This article is issued from Wikipedia - version of the 5/26/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.