Inherited or acquired thrombophilia was found in one-third of the evaluated patients, with no difference compared with the diagnostic yield obtained in the general patient series.1, 13, 23 Of note, almost all patients (93%) carried the JAK2 V617F mutation, confirming the strength of association between this mutation and vascular events.5, 26. This evidence concerns the gene JAK2 and Rare hereditary thrombophilia.