What does mismatch repair deficiency mean?
Mismatch repair is a process the body uses to repair damage to DNA. Damaged DNA can cause tumors to grow. Using mismatch repair corrects damage done to DNA to prevent a tumor from growing. Sometimes a mutation (change in DNA sequence) causes the parts of the mismatch repair system not to work, which means that it cannot fix other mutations. This leads to a higher chance of having a tumor grow.