An author's error in citing a type of leukaemia also slipped past our editorial team in this Regular Review by Annika Lindblom and Annelie Liljegren (12 February, pp 424-7). The second sentence of the last paragraph before the conclusion (p 426) should have read: “The Philadelphia chromosome in chronic myeloid leukaemia [not chronic lymphocytic leukaemia] is the best known example [of translocations creating fusion proteins in haematological diseases].”