Which of the Following Contradicts the "One- Gene, One- Enzyme

Question

Which of the following contradicts the "one- gene, one- enzyme hypothesis"?
A) A single antibody gene can code for different related proteins, depending on the splicing that takes place post- transcriptionally.
B) A mutation in a single gene can result in a defective protein.
C) Alkaptonuria results when individuals lack a single enzyme involved in the catalysis of homogentisic acid.
D) Sickle- cell anemia results in defective hemoglobin.

Accepted Answer

The one-gene, one-enzyme hypothesis proposes that each gene is responsible for coding for a single enzyme that performs a specific function. However, the splicing of pre-mRNA can result in different mRNA molecules that can ultimately be translated into different proteins. In the case of antibodies, a single gene can code for different related proteins that recognize different antigens. This contradicts the one-gene, one-enzyme hypothesis. The other choices do not contradict the hypothesis.