A gene that makes a protein called tumor protein p53. This protein is found inside the nucleus of cells and plays a key role in controlling cell division and cell death. It helps keep abnormal cells, including cancer cells, from growing. Mutations (changes) in the p53 gene may cause cancer cells to grow and spread in the body. These changes have been found in a genetic condition called Li-Fraumeni syndrome and in many types of cancer. The p53 gene is a type of tumor suppressor gene. Also called TP53 gene and tumor protein p53 gene.