Arterial thrombosis rate was found to be similar in JAK2 and MPL-mutated cases (p = 1.0); on the other hand, a non-significantly higher rate was observed in type 1/type 1-like CALR and type 2/type 2-like CALR-mutated patients in comparison with TN; p = 0.18 and p = 0.12, respectively, HR 1.9, 95% CI 0.7–5.4 and HR 2.3, 95% CI 0.8–6.4 (Table 4). This evidence concerns the gene CALR and Venous thrombosis.