Desai N, Mattsson J. HLA matching in the PTCy era: the locus still matters. Comment on: Selection of unrelated donors for allogeneic transplantation using post-transplant cyclophosphamide in acute lymphoblastic leukemia: an analysis by the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation. Haematologica; https://doi.org/10.3324/haematol.2025.289055 [Early view].