Incidence rates of major arterial/venous thrombosis for JAK2, type 1/1-like CALR, type 2/2-like CALR, MPL-mutated and TN cases were 10%/8%, 10%/5%, 8%/4%, 14%/9% and 3%/2%, respectively. The gene discussed is JAK2; the disease is Venous thrombosis.