A frameshift mutation occurs when there is an addition or deletion of one or more nucleotides that shifts the reading frame of the genetic code. In the original strand of DNA "ATG AAG TTT GGC TAA", if we were to delete a nucleotide, it would change the reading frame from that point onward.
Let's compare the provided options. The correct option must show a deletion of one or more nucleotides that shifts the reading frame:
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ATG AAG TTT GGC GCA TAA - This does not show a deletion; it adds nucleotides.
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ATG UAA GTT TGG CTA A - This also does not show a deletion and introduces non-DNA nucleotides.
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ATG AAG TTG GCT AA - This option shows a deletion of one nucleotide ('T' was deleted from "TTT"), resulting in a frameshift mutation.
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ATG TTT GGC TAA - This option indicates the deletion of one 'A' from the original sequence, which would not create a frameshift since it maintains the reading frame for the rest of the sequence.
The correct answer that represents a frameshift mutation due to deletion during replication is:
ATG AAG TTG GCT AA
1 answer