Budd-Chiari Syndrome, also known as hepatic vein thrombosis, is related to hepatic veno-occlusive disease and myeloproliferative neoplasm. An important gene associated with Budd-Chiari Syndrome is JAK2 (Janus Kinase 2), and among its related pathways/superpathways are Response to elevated platelet cytosolic Ca2+ and Collagen chain trimerization. The drugs Atezolizumab and Bevacizumab have been mentioned in the context of this disorder. Affiliated tissues include liver and spleen, and related phenotypes are splenomegaly and portal hypertension