Recommendation 1: Patients with SCD who do not have any known alloantibodies and who are anticipated to have a transfusion (either top‐up/small volume or exchange) should probably be transfused with ABO, RhD, RhCcEe, and K‐matched RBCs to reduce the risk of alloimmunisation and delayed haemolytic transfusion reactions (HTRs) (low quality of evidence, strong recommendation). The gene discussed is ABO; the disease is Schnyder corneal dystrophy.