Most cancer-associated ASXL1 mutations give rise to truncated proteins that retain the amino-terminal BAP1-interacting region of ASXL1 (ref. 15), but lose the carboxy-terminal plant-homeodomain (PHD) domain, and most often, three centrally located proline-rich regions (PPRs) as well16, 20. The gene discussed is ASXL1; the disease is cancer.