We identified differential expression of EGR1, MAP2K3 and CDKN1A at 6 h, FOSL1 and JUNB at 18 h, and EGR3 and GDF15 at 6 h and 18 h as key nodes within the p53 signalling pathway induced by 311 nm UVB in psoriasis (Figs. 4A and 5A and B and Supplementary Fig. 4A). The gene discussed is CDKN1A; the disease is psoriasis.