BRCA1 and cancer: Third, when focusing on genomic signatures present in cancer deficient in homologous recombination, HPV+ tumors do not exhibit SBS3, the single base substitution pattern found in BRCA1/2 biallelic mutated cancers defective in HR [80], and if anything, the SBS3 contribution is slightly higher in HPV-negative HNSCCs [42,80,81].