In a study of 520 patients, Loscocco et al. found a negative impact of SF3B1 mutations on OS in patients with secondary MF (HR 3.2, p = 0.002) but not PMF (HR = 1.1, p = 0.8), whereas SF3B1 mutations had no impact on leukemia-free survival in either cohort [33]. Here, SF3B1 is linked to leukemia.