https://wikimd.org/index.php?action=history&feed=atom&title=Point_mutationPoint mutation - Revision history2026-05-11T18:27:55ZRevision history for this page on the wikiMediaWiki 1.44.2https://wikimd.org/index.php?title=Point_mutation&diff=1275465&oldid=prevPrab: 1 revision imported2019-10-01T13:36:57Z<p>1 revision imported</p>
<p><b>New page</b></p><div>[[File:Point mutations-en.png|thumb|500px|Illustration of three types of point mutations.]]<br />
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A '''point mutation''' is a ''single base substitution''.<ref>{{cite web |url=http://utminers.utep.edu/rwebb/html/what_is_a_mutation_.html |title=What is a mutation? |publisher=University of Texas, El Passo |accessdate=January 23, 2017}}</ref> It is the smallest type of [[mutation]] possible.<br />
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In a point mutation, either:<br />
#a single base [[nucleotide]] is changed for another nucleotide of the genetic material (normally [[DNA]]),<ref>{{cite web |url=http://rosalind.info/glossary/point-mutation/ |title=Glossary: point mutation |publisher=Rosalind |accessdate=January 23, 2017}}</ref> or<br />
#a single base pair is inserted or deleted.<ref>{{cite web |url=https://www.ncbi.nlm.nih.gov/books/NBK21955/ |title=How DNA changes affect phenotype |author= |website= |publisher=National Center for Biotechnology Information, U.S. National Library of Medicine |accessdate=January 23, 2017}}</ref><br />
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A '''nonsense mutation''' is a point mutation in a DNA sequence that leads to an early [[stop codon]].<ref>Eldon D Enger; Frederick C Ross; David B Bailey, ''Concepts in Biology'', 12th Edition (London: McGraw-Hill, 2007), p. 158</ref> This appears as a nonsense codon in the [[transcription (genetics)|transcribed]] [[mRNA]]. Most of the time, the [[protein]] that is [[translation (genetics)|translated]] from this mRNA does not work.<br />
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== References ==<br />
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[[Category:Genetics]]<br />
[[Category:DNA]]</div>Prab