To confirm that dormant CD34+CD38- cells are sensitive to drugs that induce a double strand break response, we compared the DNA damage response in proliferating and non-proliferating CD34+CD38- leukaemia cells by inducing damage in CD34+CD38- KG-1a AML cells which had been enriched for dormancy by inhibition of the mTOR pathway. The gene discussed is CD34; the disease is acute myeloid leukemia.