CHD7 and Cerebellar hypoplasia: We also found significantly reduced cerebellar (9%) and midbrain (8%) volumes in heterozygous En1cre/+;Chd7f/+ animals (Figure 2), suggesting that the reduction in Chd7 expression in the mes/r1 in these embryos (Figures 1B,B′), had significant effects on brain development and that heterozygous Chd7 expression during cerebellar development can be sufficient to cause mild cerebellar hypoplasia.