Answer
Damaged genes could result in a mutation.
Work Step by Step
Most genes code for the production of a protein. If a gene is changed, then it could result in a protein being produced incorrectly. One example is sickle cell anemia where the sixth amino acid is changed, which causes hemoglobin to look like a sickle.
Another mutation could occur in a protooncogene. These genes are responsible for the cell cycle, and when mutated, they could cause controllable division. This is known as cancer and can lead to many complications.
