In order to understand the marked differences in SAMHD1 expression among T- and B-ALL-derived cell lines, investigation of SAMHD1 promoter methylation revealed that it was methylated in almost all T-ALL cell lines (10/11) tested, while being unmethylated in most B-ALL cell lines (13/15) [76]. Here, SAMHD1 is linked to acute lymphoblastic leukemia.