TP53 and neoplasm: However, this can be further improved by incorporating allele-specific copy number data along with allele-specific chromatin accessibility data, and (c) given that many of the mutant p53 tumours analysed here have biallelic alteration in TP53 (that is, gain-of-function mutation together with loss of wild-type TP53 allelic), the differential chromatin accessibility peaks identified can be explained by the individual as well as combined effects of loss of wild-type p53 activity and GOF mutant p53 activity.