Furthermore, since IKZF1 can bind both the canonical and cryptic internal Notch1 promoter [46], the important role of Ikzf1 loss/mutation in mouse TL as opposed to human T-ALL (where the importance of its role is contested) [47] may again be linked to species-specific mechanisms for establishing Notch signalling [44, 48]. This evidence concerns the gene IKZF1 and acute lymphoblastic leukemia.