GYPB and myelodysplastic syndrome: A prominent early progenitor cluster was also present in the MDS low-risk sample (HPCs II, cluster 1), expressing similar markers as the wild-type HPC cluster (MYB, NPM1, GATA2, HMGA and GYPB), but this cluster was really underrepresented in the high-risk MDS comprising of 6% of the total cell population as compared to 60% in low-risk MDS population (Fig. 7C, D and Supplementary Fig. 8D).