Question

A graduate student working on a project is attempting to isolate a gene from yeast. He identifies the restriction sites to cut the gene of interest out. But after several attempts, fails to do so. What could be the possible reason for the failure?

• A. Yeast genome is too complex containing overlapping genes
• B. Restriction enzyme used has recognition sites in the gene
• C. The gene of interest is too big to isolate
• D. The gene of interest in yeast is methylated

Answer 1

The correct option is B Restriction enzyme used has recognition sites in the gene

When you choose a restriction enzyme for isolating the gene of interest, you need to ensure that the enzyme should not have a restriction site in the middle of the gene. This way, the whole gene can be obtained and later used in further processes. In this case, the gene probably had a restriction site within its sequence for the restriction enzyme used. This resulted in fragmentation of the gene of interest.