Question

Which of the following mutations result in inclusion cell (I-cell) disease?

A) Mutation in lysosomal enzymes
B) Mutation in DNA repair enzymes
C) Mutation in mitochondrial DNA
D) Mutation in RNA polymerase

Answer 1

I-cell disease is caused by a mutation in lysosomal enzymes, not in DNA repair enzymes, mitochondrial DNA, or RNA polymerase. For the replication fork enzyme, DNA ligase is most likely the mutated enzyme that would impair the joining of Okazaki fragments.

Step-by-step explanation:

I-cell disease results from a mutation in the enzyme responsible for adding a mannose-6-phosphate marker to lysosomal proteins, which is necessary for their proper trafficking. The correct answer to the question is a mutation in lysosomal enzymes. Specifically, the mutation affects the enzyme UDP-N-acetylglucosamine-1-phosphotransferase. In the context of replication fork enzymes, if the joining together of Okazaki fragments is impaired, the enzyme most likely to be mutated is DNA ligase. DNA ligase is responsible for facilitating the joining of the discontinuous Okazaki fragments on the lagging strand during DNA replication.