KIT is detectable in several human tumours (Went et al, 2004), and paracrine/autocrine activation by its ligand has been suggested to be involved in numerous malignancies, including small-cell lung cancer (Hibi et al, 1991; Krystal et al, 1996), ovarian cancer (Inoue et al, 1994), neuroblastoma (Ricotti et al, 1998), breast carcinoma (Hines et al, 1995), leukaemia (Pietsch, 1993; Zheng et al, 2004), colon carcinoma (Lahm et al, 1995) and Leydig cell tumour (Kondoh et al, 1995). The gene discussed is KIT; the disease is neoplasm.