How can a gene that contains introns be made shorter (but remain functional) for genetic engineering purposes?
A) using a restriction enzyme (endonuclease) to cut the gene into shorter pieces
B) using reverse transcriptase to reconstruct the gene from its mRNA
C) using DNA polymerase to reconstruct the gene from its polypeptide product
D) using DNA ligase to put together fragments of the DNA that code for a particular polypeptide

Question

Quizplus · Accepted Answer

Reverse transcriptase can be used to make a shorter, mature mRNA copy of the gene that lacks the introns. This mRNA can then be used as a template for further genetic engineering. This process is called cDNA synthesis. Option A is incorrect because using a restriction enzyme to cut the gene into shorter pieces may result in losing important functional parts of the gene. Option C is incorrect because DNA polymerase cannot reconstruct the gene from its polypeptide product. Option D is incorrect because using DNA ligase to put together fragments of the DNA can result in loss of important genetic information.

How Can a Gene That Contains Introns Be Made Shorter