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GTR Home > Conditions/Phenotypes > Thrombocythemia 1


Thrombocythemia, or thrombocytosis, is a myeloproliferative disorder characterized by excessive platelet production resulting in increased numbers of circulating platelets. Thrombocythemia can be associated with thrombotic or hemorrhagic episodes and occasional leukemic transformation (summary by Wiestner et al., 1998). Genetic Heterogeneity of Thrombocythemia THCYT2 (601977) is caused by germline or somatic mutation in the THPO receptor gene (MPL; 159530) on chromosome 1p34, and THCYT3 (614521) is caused by germline or somatic mutation in the JAK2 gene (147796) on chromosome 9p. Somatic mutations in the TET2 (612839), ASXL1 (612990), SH2B3 (605093), and SF3B1 (605590) genes have also been found in cases of essential thrombocythemia. Somatic mutation in the CALR gene (109091) occurs in approximately 70% of essential thrombocythemia patients who lack JAK2 and MPL mutations (Klampfl et al., 2013; Nangalia et al., 2013). [from OMIM]

Genes See tests for all associated and related genes

  • Also known as: CALR1, CRT, HEL-S-99n, RO, SSA, cC1qR, CALR
    Summary: calreticulin

  • Also known as: IDDM20, LNK, SH2B3
    Summary: SH2B adaptor protein 3

  • Also known as: CAMT2, MGDF, MKCSF, ML, MPLLG, THC9, THCYT1, TPO, THPO
    Summary: thrombopoietin

Clinical features


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