Mutation
A mutation is a change in a DNA sequence. It can be as small as one base swapped for another or as large as a whole duplicated chromosome, and it arises from copying errors during replication, from chemical or radiation damage, or from mobile elements moving within the genome. Most mutations have no detectable effect, some are harmful, and a small fraction are useful in a particular environment.
Why it matters
It is the only original source of new genetic variation; everything selection, drift, and breeding do afterwards is a rearrangement of what mutation supplied.
Also written: mutations, mutant
Where it comes up
Read about Mutation on Wikipedia
Sources
- Mutation Wikipedia
- Genetic Mutation Nature Education Scitable
- Mutation NHGRI Talking Glossary of Genetic Terms
