Question

Which of the following codon mutations are synonymous? Select one or more: a. CUU to CUC b. ACU to ACA c. UCU to CCU d. CAA to AAA

Answer 1

The synonymous codon mutations are CUU to CUC, ACU to ACA, and UCU to CCU.

Step-by-step explanation:

A synonymous mutation is a mutation in a DNA sequence that does not result in a change in the amino acid sequence of the resulting protein. In this case, codon mutations are considered synonymous if they still specify the same amino acid.

Among the given options, the synonymous codon mutations are:

CUU to CUC (both code for leucine)

ACU to ACA (both code for threonine)

UCU to CCU (both code for proline)

Codon mutations CAA to AAA change the amino acid from glutamine to lysine and are therefore nonsynonymous.

Answer 2

The synonymous mutations are a. CUU to CUC and b. ACU to ACA.

Synonymous mutations are those that result in a change of the DNA sequence but do not lead to a change in the encoded amino acid during protein synthesis. In the given options:

a. CUU to CUC: This mutation is synonymous because both CUU and CUC code for the amino acid leucine (Leu).

b. ACU to ACA: This mutation is synonymous because both ACU and ACA code for the amino acid threonine (Thr).

c. UCU to CCU: This mutation is non-synonymous because UCU codes for serine (Ser) while CCU codes for proline (Pro), leading to a change in the amino acid.

d. CAA to AAA: This mutation is non-synonymous because CAA codes for glutamine (Gln) while AAA codes for lysine (Lys), resulting in a change in the amino acid.

So, the synonymous mutations are a. CUU to CUC and b. ACU to ACA.