Importantly, this effect of SOS1 ablation, abolishing the development of CML-linked hematological alterations, is clearly specific since the analysis of non-transgenic mice of the same ages and SOS1/2 genotypes showed similar unchanged profiles for all these parameters in WT SOS1-KO and SOS2-KO mice (Figure 3B, lower). Here, SOS2 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.