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Editing the mRNA of a gene changes a UGA codon to AGA. what will this lead to?

A. cause an amino acid substitution which increases the length of the polypeptide
B. introduce an extra reading frame by creation of a methionine codon
C. introduce a frameshift mutation coding for a nonsense polypeptide
D. introduce a premature stop codon resulting in a truncated protein
Hi,
What level of study/exam is this? At A level, I don't think they expect you to know that UGA is a STOP codon i.e. that it signifies that the nascent peptide chain should end there.

If you look at this link, you will see that AGA codes for the a.a. arginine.
This table shows the 64 codons and the amino acid each codon codes for (columbia.edu)

So in this Q, instead of ending the synthesis of the protein/polypeptide in question, an extra arginine will be added. So I should think the answer is "A".

M [specialist biology tutor]
Reply 2
Original post by macpatgh-Sheldon
Hi,
What level of study/exam is this? At A level, I don't think they expect you to know that UGA is a STOP codon i.e. that it signifies that the nascent peptide chain should end there.

If you look at this link, you will see that AGA codes for the a.a. arginine.
This table shows the 64 codons and the amino acid each codon codes for (columbia.edu)

So in this Q, instead of ending the synthesis of the protein/polypeptide in question, an extra arginine will be added. So I should think the answer is "A".

M [specialist biology tutor]

okk that's what I put (:
this is uni level biomedical science lol but i didn't do a level bio/chem so idk much to begin with
Original post by t0es
okk that's what I put (:
this is uni level biomedical science lol but i didn't do a level bio/chem so idk much to begin with

Good to hear!
I have heard the phrase "from head to toe" but how you changed from "friedegg to toe" only heaven knows lol :lol:
Reply 4
Original post by macpatgh-Sheldon
Good to hear!
I have heard the phrase "from head to toe" but how you changed from "friedegg to toe" only heaven knows lol :lol:

LOL i have 2 accs, im signed into one from my phone so i still get notifs there ahahah

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