Trisomy 21 and GATA1 mutation in clonal proliferation: case series of non-classical presentations in individuals with and without Down syndrome

Introduction: Transient abnormal myelopoiesis (TAM) and myeloid leukaemia of Down syndrome (ML-DS) are caused by cooperation between trisomy 21 (T21) and acquired GATA1 mutation. We describe three cases that differ from classic TAM and ML-DS but still demonstrate the interplay between T21 and GATA1 mutation with resultant clonal proliferation.