Question

If the guanine (G) in the DNA sequence 3’ TTACGTTTC is deleted, what are the first 2 amino acids that will be joined at the ribosome? Remember there is a START codon. Use the information on this chart to answer the question.

asparagine, alanine

methionine, glutamine

leucine, glycine

leucine, phenylalanine

methionine, lysine

The mutation in the above question is an example of a ________________ mutation.

Group of answer choices

frameshift

nonsense

missense

silent

Answer 1

• When the guanine is present in sequence 3’ TTACGTTTC, the sequence is transcribed and from the start codon, the sequence will begin to translate to add methionine and glutamine to the peptide sequence.
• If guanine is deleted from the sequence then the sequence mutated is 3’ TTACTTTC, which upon transcription forms the mRNA having sequence 3'AAUGAAAG which upon translation incorporates methionine(AUG) as the first amino acid and lysine as the second amino acid (AAA) in the peptide sequence.
• the mutation in the above question is an example of a frameshift mutation because by deleting the nucleotide, the reading pattern of amino acid is changed from methionine and glutamine to methionine and lysine that's is why it is called frameshift mutation