Eaf2 knockout mice on a mixed genetic background developed lung adenocarcinoma, hepatocellular carcinoma, B-cell lymphoma, and high-grade prostate intraepithelial neoplasia while EAF2 deficiency on a C57BL/6 background developed prostatic intraepithelial neoplasia but lacked macroscopic tumours in other organs24, 45. The gene discussed is EAF2; the disease is prostate intraepithelial neoplasia.