TP53 and neoplasm: Simply, p53 mutations can be divided into three groups17,18: (1) loss of function, where p53 mutation leads to loss of tumor suppressor function of p53, (2) dominant negative, where a mutant copy hetero-oligomerizes with a wild-type (WT) copy poisoning the WT tumor suppressor function, and (3) GOF, where the cells acquire a new dominant oncogenic property leading to oncogenesis.