Although a prior study had identified TP53 as necessary for DUX4-induced cell death in some cells [5], we found that human myoblasts with CRISPR mutated TP53 and the RD rhabdomyosarcoma cell line that does not contain a functional TP53 allele [17,18] both succumbed to DUX4-induced cell death as efficiently as primary human myoblasts (S1A–S1D Fig). This evidence concerns the gene DUX4 and rhabdomyosarcoma.