Editing Chromosomal translocation (section)

{{Short description|Phenomenon that results in unusual rearrangement of chromosomes}}
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[[File:Translocation-4-20.png|thumb|Chromosomal reciprocal translocation of the 4th and 20th [[chromosome]].]]
In [[genetics]], '''chromosome translocation''' is a phenomenon that results in unusual rearrangement of chromosomes. This includes "balanced" and "unbalanced" translocation, with three main types: "reciprocal", "nonreciprocal" and "Robertsonian" translocation. Reciprocal translocation is a [[chromosome abnormality]] caused by exchange of parts between non-homologous [[chromosomes]]. Two detached fragments of two different chromosomes are switched. Robertsonian translocation occurs when two non-homologous chromosomes get attached, meaning that given two healthy pairs of chromosomes, one of each pair "sticks" and blends together homogeneously. Each type of chromosomal translocation can result in disorders for growth, function and the development of an individuals body, often resulting from a change in their genome.<ref name=eurogentest>{{Cite web|url=http://www.eurogentest.org/index.php?id=612|title=EuroGentest: Chromosome Translocations|website=www.eurogentest.org|access-date=2019-03-29|archive-date=January 24, 2018|archive-url=https://web.archive.org/web/20180124111046/http://www.eurogentest.org/index.php?id=612|url-status=dead}}</ref>

A [[gene fusion]] may be created when the translocation joins two otherwise-separated genes. It is detected on [[cytogenetics]] or a [[karyotype]] of affected [[cell (biology)|cells]].  Translocations can be balanced (in an even exchange of material with no genetic information extra or missing, and ideally full functionality) or unbalanced (in which the exchange of [[chromosome]] material is unequal resulting in extra or missing [[gene]]s).<ref name=eurogentest/><ref>{{cite web |title=Can changes in the structure of chromosomes affect health and development? |url=https://ghr.nlm.nih.gov/primer/mutationsanddisorders/structuralchanges |website=Genetics Home Reference |publisher=National Library of Medicine |access-date=15 July 2020 |language=en}}</ref> Ultimately, these changes in chromosome structure can be due to deletions, duplications and inversions, and can result in 3 main kinds of structural changes.