CXCR4 and HIV-1 infection: From a clinical study, the Essen Patient, who was a 27-year-old patient with HIV-1 infection and anaplastic large-cell lymphoma, received a HLA-compatible CCR5∆32 stem cell transplantation, which was similar to the Berlin Patient. However, the outcome was that the virus switched to be CXCR4 preferential X4-tropic HIV-1, which indicated that editing only CXCR4 or CCR5 may not be sufficient [45].