Finally, to demonstrate that some cancer methylated genes are also frequently methylated in somatic progenitor stem cells and that their methylation is important for lineage specification, we considered two genes: RUNX3 and AIM2. We selected RUNX3 because, in agreement with previously published data [24], our methylation arrays showed that, relative to CD34+ cells, RUNX3 was hypomethylated in peripheral lymphocytes but not in peripheral neutrophils. Here, AIM2 is linked to cancer.