Mutations in DNA-polymerase-Beta occur in breast, prostate and colorectal tumors.

To determine the tissue specificity of the potential mutations in DNA polymerase beta (pol beta), alterations in the pol beta were examined in breast, prostate, and colorectal primary tumors. The pol beta is known to contribute to mammalian base excision repair and replication. Similar to colorectal cancer, a high occurrence of mutations as 87-bp deletion in the catalytic domain of the pol beta removing 29 amino acids was observed in breast cancer. Contrary to breast and colorectal tumors, a low occurrence of mutation as a single base (T) deletion at the position coding for amino acid 181 of the pol beta was associated with prostate cancer. The missing T changed the codon from TTC to TCA (phenylalanine to serine), causing a frame shift.