Heterozygous de novo germline mutations that result in truncations that lead to loss of the C-terminal region of ASXL3 (ref. 23) have also been documented in the Bohring–Opitz syndrome; similarly, heterozygous ASXL2 mutations that would result in premature truncations have been reported in pediatric acute myeloid leukemia cases20. Here, ASXL2 is linked to acute myeloid leukemia.