ASXL1 and mast cell neoplasm: Two other ASXL1 variants identified in this study, ASXL1 p.Leu731Tyrfs*12 (Sample 09, overt-PMF) and Q1433Q (Sample 03, ET) were also putative novel variants with no dbSNP, COSMIC or ClinVar data; whereas the ASXL1 p.Tyr591*variant (Sample 10, overt-PMF) has been reported in various diseases including ET and MF [9, 20], MDS [21], chronic myelomonocytic leukaemia [22], AML [23], mast cell neoplasm [24] and CNL [25], as well as breast cancer [26], but has not been previously reported in PV (Table 2).