The ASXL1 gene is often somatically mutated in patients with hematopoietic malignancies such as MDS, MPN and AML, generally through acquired heterozygous nonsense or frame-shift mutations (Abdel-Wahab et al., 2011; Bejar et al., 2011; Boultwood et al., 2010a,b; Gelsi-Boyer et al., 2012, 2010; Inoue et al., 2013). Here, ASXL1 is linked to myeloproliferative neoplasm.