WBP1L and leukemia: WW domain binding protein 1‐like (WBP1L) also known as outcome predictor of acute leukaemia 1 (OPAL1) has attracted attention because of a report showing that its elevated expression at mRNA level correlates with favourable outcome in childhood acute lymphoblastic leukaemia (ALL).1 These data suggested that it could potentially serve as a prognostic marker.