Remarkably, the transplantation of allogeneic, CRISPR-edited, CCR5-ablated HPSCs into a patient with HIV-1 infection and acute lymphoblastic leukemia resulted in long-term engraftment of genetically modified HSPCs, yet with only 5% CCR5 disruption rates in lymphocytes [52]. The gene discussed is CCR5; the disease is acute lymphoblastic leukemia.