Although the α-klotho promoter sequences are not well conserved between human and mouse, both include potential binding sites for E2F transcription factors, which are critical downstream mediators of the p16INK4a–retinoblastoma tumour suppressor pathway6, at the same position from the α-klotho translation start sites (Figs 6a and 7b). The gene discussed is KL; the disease is neoplasm.