Editing Mutation (section)

==== Somatic mutation ====
{{main|Somatic mutation}}

A change in the genetic structure that is not inherited from a parent, and also not passed to offspring, is called a [[somatic cell|somatic]] mutation''.<ref name="Somatic_cell" />'' Somatic mutations are not inherited by an organism's offspring because they do not affect the [[germline]]. However, they are passed down to all the progeny of a mutated cell within the same organism during mitosis. A major section of an organism therefore might carry the same mutation. These types of mutations are usually prompted by environmental causes, such as ultraviolet radiation or any exposure to certain harmful chemicals, and can cause diseases including cancer.''<ref>{{Cite encyclopedia|url=https://www.britannica.com/science/somatic-mutation|title=somatic mutation {{!}} genetics|access-date=31 March 2017|url-status=live|archive-url=https://web.archive.org/web/20170331122201/https://www.britannica.com/science/somatic-mutation|archive-date=31 March 2017|encyclopedia=Encyclopædia Britannica}}</ref>''

With plants, some somatic mutations can be propagated without the need for seed production, for example, by [[grafting]] and stem cuttings. These type of mutation have led to new types of fruits, such as the "Delicious" [[apple]] and the "Washington" navel [[Orange (fruit)|orange]].<ref>{{cite book | vauthors = Hartl L, Jones EW |url=https://archive.org/details/geneticsprincipl00hart/page/556|title=Genetics Principles and Analysis|publisher=Jones and Bartlett Publishers|year=1998|isbn=978-0-7637-0489-6|location=Sudbury, Massachusetts|pages=[https://archive.org/details/geneticsprincipl00hart/page/556 556]|url-access=registration}}</ref>

Human and mouse [[somatic cell]]s have a mutation rate more than ten times higher than the [[germline]] mutation rate for both species; mice have a higher rate of both somatic and germline mutations per [[cell division]] than humans. The disparity in mutation rate between the germline and somatic tissues likely reflects the greater importance of [[genome]] maintenance in the germline than in the soma.<ref name="Milholland">{{cite journal | vauthors = Milholland B, Dong X, Zhang L, Hao X, Suh Y, Vijg J | title = Differences between germline and somatic mutation rates in humans and mice | journal = Nature Communications | volume = 8 | pages = 15183 | date = May 2017 | pmid = 28485371 | pmc = 5436103 | doi = 10.1038/ncomms15183 | bibcode = 2017NatCo...815183M }}</ref>