Question

Which cytosine in the following sense strand of DNA could cause the most damage to the organism if it is deaminated?

A-T-G-T-C-G-C-T-A-A-T-C

Short answer

The only cytosine that will change the amino that is incorporated into the peptide is the first one. Therefore, this is the cytosine that could cause the most damage to an organism if it were deaminated.

Step-by-step solution

Sense strand in DNA

The sense strand is a strand of DNA that has the same sequence as mRNA.mRNA is a messenger RNA which involved in protein synthesis.

The sequence of bases in the sense strand of DNA would result in the formation of that fragment of mRNA is as follows;

Deamination of the sense strand

If deamination does not occur then the mRNA sequence will be:

AUG-UCG-CUA-AUC, which will code for the following tetrapeptide:

Met-Ser-Leu-Ile

Deamination of cytosine results in the uracil. If the cytosine is deaminated, the mRNA sequence will be:

AUG-UUG-UUA-AUU, which will code for the following tetrapeptide:

Met-Leu-Leu-Ile

The only cytosine that will change the amino that is incorporated into the peptide is the first one. Therefore, this is the cytosine that could cause the most damage to an organism if it were deaminated.