Current Recombinant Cloning Technology
Reverse transcriptase is an enzyme that acts opposite of normal transcriptase. It uses RNA to code for DNA. It is also found in the virus linked to AIDS.
A more advanced method of producing DNA clones uses the enzyme reverse transcriptase and mRNA in a four-step process, which creates a pure segment of desired genes:
- mRNA is made by a selected cell particularly for its genetic characteristics.
- mRNA splices out the interons.
- mRNA is isolated and used as a template with reverse transcriptase to make the complementary DNA.
- The DNA product therefore contains only the desired DNA segment and the host cell will continue to produce the product.
With this type of emerging technology, the “shotgun” approach to cloning is simplified by not copying the entire genome of the individual, but only the specific genes required.
Excerpted from The Complete Idiot's Guide to Biology © 2004 by Glen E. Moulton, Ed.D.. All rights reserved including the right of reproduction in whole or in part in any form. Used by arrangement with Alpha Books, a member of Penguin Group (USA) Inc.