Thus, T cell restricted transgenic expression of a virus host modification gene (A238L of ASFV) inhibiting transcription mediated by both p65 (NF-κB) and NFAT has resulted in a transformation event at the CD4+CD8+ stage of T cell development yielding an aggressive (mono-)oligoclonal, angiogenic, metastasising and transplantable CD4+CD8+CD69− lymphoma. The gene discussed is NFKB1; the disease is lymphoma.