The frequency of APOBEC3B-deletion alleles is ~50% in 143 genotyped oral squamous cell carcinoma -Taiwan samples (27A3B−/−:89A3B+/−:27A3B+/+), compared to the 5.8% found in 314 OSCC-TCGA samples. This evidence concerns the gene APOBEC3B and oral cavity squamous cell carcinoma.