In our study, thrombotic events were observed in 9% and 18% of patients with ET and PMF carrying CALR mutation, respectively, which were not significantly different from those carrying JAK2 V617F mutation (13% [7/55], p = 0.636; 17% [5/29], p = 0.972, respectively) (data not submitted). The gene discussed is CALR; the disease is essential thrombocythemia.