TP53 and breast cancer: The disease can be triggered by a rare inherited gene mutation with high or low penetrance in carriers, and cause so-called familial syndromes, i.e., breast or ovarian cancer with breast cancer gene 1 (BRCA1) or breast cancer gene 2 (BRCA2) mutations, and Li-Fraumeni syndrome associated with rare tumor protein P53 (TP53) variants that lead to development of soft tissue sarcomas, breast cancer, colon cancer, gastric cancer, and brain tumors [22].