09-27-2008, 06:22 PM
C is the correct answer
This patient has a splice site mutation. The splice site is located within the intron. The removal of the splice site causes the mutant gene to retain an intron and results in the production of an abberant protein. In this case, the added intron contains a stop codon and causes the translation of the protein to terminate at codon 428. This explains why the mRNA is longer than normal but the protein is shorter.
A mutation in the enhancer or the promoter may cause weaker expression of the mutant protein but would not affect its length.
A mutation in one of the exons may create a stop codon which causes translation to terminate early, but would not create a longer mRNA.
A mutation in the start codon would cause the mutant protein not to be expressed at all.
This patient has a splice site mutation. The splice site is located within the intron. The removal of the splice site causes the mutant gene to retain an intron and results in the production of an abberant protein. In this case, the added intron contains a stop codon and causes the translation of the protein to terminate at codon 428. This explains why the mRNA is longer than normal but the protein is shorter.
A mutation in the enhancer or the promoter may cause weaker expression of the mutant protein but would not affect its length.
A mutation in one of the exons may create a stop codon which causes translation to terminate early, but would not create a longer mRNA.
A mutation in the start codon would cause the mutant protein not to be expressed at all.