Definition

A term used to describe a change in the DNA sequence of a gene that is seen for the first time in a person and has not appeared in previous generations. A new mutation can explain how a person can have a genetic condition that did not occur in his or her parents. A new mutation can occur in an egg or sperm cell of a parent, in the fertilized egg soon after the egg and sperm unite, or in another type of cell during embryo development. A person who has a new mutation may pass the mutation to his or her child. Some new mutations may lead to cancer or other diseases. Also called de novo mutation, de novo variant, and new variant.