GATA1 and leukemia: Together, these studies have implicated increased expression of various genes on chromosome 21, in particular ERG and DYRK1a, as important mediators of the abnormal megakaryopoiesis, although this does not seem to be sufficient to cause leukaemia in trisomic or disomic mouse models even when co-expressed with an N-terminally truncated GATA1 gene.