In the MPN cohort, the usual representation of JAK2V617F, CALR and MPL mutants was respected since it included 55/75 (73.3%) patients with a JAK2V617F-mutated MPN (27 PV, 21 ET, 7 PMF), 16/75 (21.3%) patients with a CALR-mutated MPN (15 ET, 1 PMF) and 2 ET patients with an MPL mutation (2/75 or 2.7%). The gene discussed is CALR; the disease is essential thrombocythemia.