Iles and associates [18] measured human chorionic gonadotrophin (hCG) and alpha-feto-protein (AFP) in culture media from a panel of 29 cell lines including 9 bladder carcinomas, 5 'normal' bladder epithelia, 10 germ cell tumours, and 5 miscellaneous tumours and 'normal' cell lines. The gene discussed is AFP; the disease is germ cell tumor.