Uploaded December 2024 | Updated September 2026, 1 day ago

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In this video, we look at substitution mutations. First we look at how changes to DNA can take place, including the role of mutagens. We then look at what is meant by a substitution mutation. We explore how substitution mutations can be silent, due to the degenerate nature of the genetic code. We then explore how substitution mutations can affect the structure of an encoded protein either by changing an amino acid or introducing a stop codon.

Image credits:

DNA Animation
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brian0918, Public domain, via Wikimedia Commons

Adenine nucleotide
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Hbf878, CC0, via Wikimedia Commons

Epstein Barr virus
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Liza Gross, CC BY 2.5 creativecommons.org/licenses/by/2.5, via Wikimedia Commons

Cigarette smoke
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Challiyil Eswaramangalath Vipin from Chalakudy, India, CC BY-SA 2.0 creativecommons.org/licenses/by-sa/2.0, via Wikimedia Commons

X ray
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Ptrump16, CC BY-SA 4.0 creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons