DUSP4 and medulloblastoma: While we have not taken the observation further it is worthy of additional study since the fly ortholog of CHD7 (and CHD8), kismet, is known to antagonize PcG-mediated repression during development.80,81 In G4 human medulloblastoma cells, CHD7 creates a less accessible chromatin conformation thereby preventing BMI1 repression of DUSP4,82 and more recent studies demonstrated the presence of a CHD7-BMI1-MAPK regulatory axis,83 so one specific example of PcG-CHD7 interaction already exists.