Molecular composition and main characteristics of MDS molecular groups. Each row represents a molecular subgroup, and molecular features are ordered by blocks of gene mutations, chromosomal losses, gains, rearrangements, and cnLOH events. For each subgroup, the relative proportions of (1) the number of mutated genes per patient, (2) the number of cytogenetic alterations per patients, (3) the proportion of BM blasts, and (4) IPSS-M risk category are indicated as stacked bar plots. H, high; L, low; MH, moderate high; ML, moderate low; VH, very high; VL, very low.