Question

You are studying a eukaryotic gene that codes for the alpha-subunit in hemoglobin. what is the most likely result if base substitutions occur in the first nucleotide at the 5' end of an intron and also in the last nucleotide at the 3' end?

Answer 1

Below are the choices:

There will be no change in the polypeptide coded by this gene because introns are not expressed.

A change in reading frame will alter all amino acids in the polypeptide past the point of the first substitution.

A change in reading frame will alter all amino acids in the polypeptide past the point of the second substitution.

This intron will not be removed during pre-mRNA splicing because the spliceosome will not recognize the intron-exon junctions.

Each base substitution is likely to alter only one amino acid in the final polypeptide chain.

The answer is This intron will not be removed during pre-mRNA splicing because the spliceosome will not recognize the intron-exon junctions.