Lack of SUV39H1 expression resulted in a significant decrease of H3K9me3 (Supplementary Fig. 5b) and an increase in ERV expression (Supplementary Fig. 5c), indicating that ERV repression was dependent on SUV39H1 expression in TP53mut DLBCL. The gene discussed is SUV39H1; the disease is diffuse large B-cell lymphoma.