TP53 was the most frequently mutated gene in all evaluated cancer types (26.9% of all cancers, 22.9%-43.9% in specific cancer types), while MLL3, ATM, PRKDC, BRCA2, POLQ, ATR, POLE, and REV3L were also within the top 20 list of all 6 groups, BRCA1 and FANCM in the top 20 for 5 of the 6 groups, and CENPE, SLX4, CDK12, SHPRH, and FANCD2 within the top 20 most frequently mutated DNA repair genes in 4 of the 6 evaluated groups. The gene discussed is ATR; the disease is cancer.