BIOLOGY
NUCLEIC ACIDS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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This substitution mutation produces a stop codon, will produce a shortened/truncated protein, prevents any other amino acids from being added after the location where the mutation occurs.
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This type of substitution mutation changes a single amino acid
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This is a type of substitution mutation which does not change the amino acid sequence
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None of the above
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Detailed explanation-1: -A nonsense mutation occurs in DNA when a sequence change gives rise to a stop codon rather than a codon specifying an amino acid. The presence of the new stop codon results in the production of a shortened protein that is likely non-functional.
Detailed explanation-2: -(NON-sens myoo-TAY-shun) A genetic alteration that causes the premature termination of a protein. The altered protein may be partially or completely inactivated, resulting in a change or loss of protein function.
Detailed explanation-3: -Stop codons are also called nonsense codons because they do not code for an amino acid and instead signal the end of protein synthesis. Thus, nonsense mutations occur when a premature nonsense or stop codon is introduced in the DNA sequence.
Detailed explanation-4: -Examples of diseases induced by nonsense mutations include: Cystic fibrosis (caused by the G542X mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) Beta thalassaemia (-globin) Hurler syndrome.
Detailed explanation-5: -A nonsense mutation results in the addition of a premature stop codon, creating a truncated protein product. A silent mutation is a mutation that occurs within the DNA sequence, but does not alter the amino acid sequence.