Features include always present findings: Elevated platelet count (thrombocytosis), Impaired collagen-induced platelet aggregation, Impaired epinephrine-induced platelet aggregation, and Impaired ADP-induced platelet aggregation; and sometimes findings: Enlarged spleen (splenomegaly).

CALR

CALR encodes calreticulin (417 aa). Calcium-binding chaperone that promotes folding, oligomeric assembly and quality control in the endoplasmic reticulum (ER) via the calreticulin/calnexin cycle. Highest expression in Cells Cultured fibroblasts (2,150 TPM) and Thyroid (1,315 TPM).

Thrombocythemia 1 is associated with mutations in the CALR gene on chromosome 19.

The CALR protein participates in CALR, TAP, TAPBP dissociate from SEC22B:STX4, SEC22B, CALR, STX4, TAP and TAPBP bind, and Expression of Calreticulin pathways.

CALR is classified as a druggable target (Cell Surface, Clinically Actionable, Druggable Genome, External Side Of Plasma Membrane, and Nuclear Hormone Receptor categories) with score 13.1.

SH2B3

SH2B3 function has not been fully characterized.

Thrombocythemia 1 is associated with mutations in the SH2B3 gene on chromosome 12.

THPO

Genetic testing for CALR, SH2B3, THPO is available. Testing is considered confirmatory for diagnosis.

Biomarker and diagnostic research for thrombocythemia 1 has been reported in the published literature.

Phenotype severity distribution: 4 always present features.

No clinical trials have been registered for thrombocythemia 1.

64 publications have been identified in PubMed for thrombocythemia 1. Research spans Review / Meta-Analysis (22%), Case Report / Case Series (22%), and Epidemiology / Natural History (17%).