ASXL1 and myelodysplastic syndrome: However, in other studies, knockout of Asxl1 led to systemic developmental defects including MDS-like presentation, with alteration of the self-renewal and repopulation capacities of the mutant hematopoietic stem/progenitor cells and global reduction of H3K27 tri-methylation (H3K27me3) [17, 18].