Dilated cardiomyopathy (DCM) is a common cause of sudden death and heart failure. Many mutations can cause DCM, but several of them are linked to the protein troponin, which is an essential protein that helps regulate muscle contraction in the heart.
-A mutation in troponin that has been linked to DCM is A159E, in which the amino acid A is replaced by the amino acid E. The middle portion of the exons (template strand of DNA) that contain the code for the wild-type A and the mutant E are shown in the accompanying table. Assuming that the reading frame starts with the first triplet, what is the codon for A? $\begin{array} { | c | c c c | }
\hline \text { Wild-type } & 3 ^ { \prime } & \text { ATGCGTTAGCTC } & 5 ^ { \prime } \
\text { Mutant } & 3 ^ { \prime } & \text { ATGCTTTAGCTC } & 5 ^ { \prime } \
\hline
\end{array}$

Question

Dilated cardiomyopathy (DCM) is a common cause of sudden death and heart failure. Many mutations can cause DCM, but several of them are linked to the protein troponin, which is an essential protein that helps regulate muscle contraction in the heart.
-A mutation in troponin that has been linked to DCM is A159E, in which the amino acid A is replaced by the amino acid E. The middle portion of the exons (template strand of DNA) that contain the code for the wild-type A and the mutant E are shown in the accompanying table. Assuming that the reading frame starts with the first triplet, what is the codon for A? $\begin{array} { | c | c c c | } 
\hline \text { Wild-type } & 3 ^ { \prime } & \text { ATGCGTTAGCTC } & 5 ^ { \prime } \
\text { Mutant } & 3 ^ { \prime } & \text { ATGCTTTAGCTC } & 5 ^ { \prime } \
\hline
\end{array}$

Quizplus · Accepted Answer

The wild-type DNA sequence 3' ATGCGTTAGCTC 5' corresponds to the mRNA sequence 5' UACGCAAUCGA 3'. The codon for A (Alanine) is GCA, which matches option A.

Dilated Cardiomyopathy (DCM) Is a Common Cause of Sudden Death