However, progression to ML-DS was independent of trisomy 21 in this study, but required synergy between mutations in GATA1 and the cohesin genes, in particular cohesin subunit SA-2 (STAG2) knockout occurring in fetal or early postnatal but not adult HSCs (Wagenblast et al., 2021). The gene discussed is STAG2; the disease is Dravet syndrome.