To determine the type of mutation represented by the change from sequence #1 to sequence #2, we need to analyze the base change.
In sequence #1:
5' - AGCGTTACCGT - 3'
In sequence #2:
5' - AGGCGTTACCGT - 3'
The change here is from "C" (in #1) to "G" (in #2) at the second position of the sequence.
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Frameshift mutation: This type of mutation involves insertions or deletions of nucleotides, which would shift the reading frame and likely alter downstream amino acid sequences. Since there is no insertion or deletion in this case, it is not a frameshift mutation.
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Missense mutation: This type of mutation results in the substitution of one amino acid for another in a protein due to a change in the DNA sequence. This is a possibility since the change from "C" to "G" could potentially result in a different amino acid being coded.
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Silent mutation: This type of mutation does not change the amino acid sequence even though the DNA sequence may change. For this to be the case, the codon corresponding to the mutation would need to code for the same amino acid as before.
To figure out if this is a missense or silent mutation, we need to look at the codons. Each codon consists of three nucleotides, so we can break the sequences into codons:
For sequence #1:
- AGC (Serine)
- GTT (Valine)
- ACC (Threonine)
- GT (this is incomplete and usually doesn't count in standard codonization)
For sequence #2:
- AGG (Arginine)
- CGT (Arginine)
- TAC (Tyrosine)
- CGT (same as before)
Since the first triplet in #2 (AGG) codes for a different amino acid (arginine) compared to the first triplet in #1 (AGC, which codes for serine), this mutation is classified as a missense mutation.
Thus, the answer is a missense mutation.