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Beta thalassemia is a disorder caused by mutations in the HBB gene. Examination of the HBB protein in an individual with beta thalassemia shows that the protein is missing many amino acids at its carboxyl terminus. Which of the following is the most likely explanation for how a mutation in the DNA could result in the loss of the carboxyl terminus of the HBB protein?

a. The mutation keeps the HBB gene wrapped tightly around histones, preventing transcription of the gene.
b. The mutation changes the promoter sequence of the gene such that different transcription factors initiate transcription of the gene.
c. The mutation changes a codon in the coding region of the HBB transcript to a stop codon such that translation terminates earlier than it should.
d. The mutation results in hydrogen bonds between adjacent amino acids instead of covalent bonds, resulting in the production of an unstable protein.

2 Answers

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Answer:

c. The mutation changes a codon in the coding region of the HBB transcript to a stop codon such that translation terminates earlier than it should.

User RecencyEffect
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Answer:

The correct answer is - option C. The mutation changes a codon in the coding region of the HBB transcript to a stop codon such that translation terminates earlier than it should.

Step-by-step explanation:

As we know the mutant HBB gene that causes thalassemia disorder in an individual, produces a protein that lacks many amino acids. This gene produces shorter protein than the normal HBB gene.

A nonsense mutation takes place in a gene that alters codons so that a stop codon comes before its normal place and generates a shorter or truncated protein product with missing amino acids.

Thus, the correct answer would be - option C.

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