AEG-1 was first reported in 2002 as a neuropathology-associated gene induced in human foetal astrocytes following human immunodeficiency virus-1 (HIV-1) infection or treatment with recombinant HIV-1 envelope glycoprotein (gp120), and it has emerged as a potentially crucial mediator of malignancy in cancers and a key node in a complex network of oncogenic signalling pathways9,10. The gene discussed is ERVW-1; the disease is cancer.