Compared with JAK2 V617F-positive patients, CALR-mutation patients had lower leukocyte counts (9.6 × 10<sup>9</sup>/L vs. 10.9 × 10<sup>9</sup>/L), lower hemoglobin (Hb) and hematocrit (Hct) levels, higher platelet counts (1078.5 × 10<sup>9</sup>/L vs. 858.1 × 10<sup>9</sup>/L), and lower total thrombosis rates (20.8% vs. 37.8%), while the CALR-mutated and triple-negative patients had lower venous thrombosis rates than in the JAK2 V617F-positive patients. This evidence concerns the gene CALR and Venous thrombosis.