A similar analysis of the mean exome/genome covariates among 33 cancer types resulted in five PCs (explaining 77.6% of the variability; Supplementary Table S5), including (1) seven DRR defects, all APOBEC/ADAR mutations, and A4 mRNA levels; (2) A3C-H and AICDA mRNA levels; (3) UV factor and ADARB1/A3C/ADARB2 mRNA levels; (4) A3A and A3B mRNA levels; and (5) age and A1/ADAR mRNA levels. Here, AICDA is linked to cancer.