mutation

A mutation is a change in the DNA of a cell, the genetic material that determines how a cell behaves and reproduces. Mutations can occur from a copying error during cell division, from external influences such as radiation, or they can be present at birth and passed from parent to child. Some mutations have no noticeable effect, while others cause a cell to grow uncontrollably, as in cancer. In many incurable diseases, a mutation plays a role in the development of the disease, and increasingly, treatment targeting that specific mutation is being investigated.