The p53 gene is a recessive tumor suppressor gene which functions as a key regulator for the cell cycle. In the event when only one p53 allele is mutated then the function of the p53 gene will persist and apoptosis (programmed cell death) will proceed if there are significant gene mutations in the cell. If two p53 alleles are mutated then the cell will not receive the signal to apoptose even with significant mutations and cancer will develop.
