Important diseases are caused by mutations in some genes of DNA, like cancer and several neurologic diseases. These mutations are corrected in healthy humans by a complex mechanism triggered by the proteins ATM, CHK2 and p53. These proteins cause apoptosis, whenever the transcription error in DNA is too large to be corrected.This mechanism does not work if the genes encoding several proteins, mainly ATM, CHK2 and p53, are naturally mutated or are experimentally removed in rats using CRISPR or similar processes.We claim the therapeutic use of the proteins ATM, CHK2 and p53 to activate the natural mechanism of DNA transcription correction.These proteins are identical to those existing in healthy cells, and are already being produced for research or diagnosis purposes by monoclonal processes.