The reason we do this

The reason we do this
A walk with the Coys

Tuesday, August 5, 2014

What is a GMO? What is Genetic Engineering? From the perspective of a Science Teacher :)

Lately, I have had a few people ask my science teacher side to explain what exactly Genetically Modified Organisms and Genetic Engineering entail.  Let me start by saying, I am NOT the expert, but I did find a couple of reference that I think help explain the terms.  By definition, they are organisms that have modified on the genomic level.  So their strand of DNA (A-T, G-C Double helix structure that give you the instructions for all protein structures in an organism) has been modified or altered in some way.  The same thing happens when you have a baby.. some of the DNA from Mom and some of the DNA from Dad are expressed to make a new, stronger , healthier baby (if all goes according to plan).  Sometimes random mutations happen and the new baby can be even healthier, or sadly, sometimes random mutations occur that make the new baby not quite as strong or healthy.  Its all very random through the normal processes of reproduction. 

As we as a culture and a species became much more in tuned with what was happening, we would purposely breed two creatures or plants to attempt to make offspring that had the desired traits.  This works just fine, and its called selective breeding.  Do you like your kitty or pooch?  Thank selective breeding!  The problem?  Selective breeding is kind of a shot in the dark.  You don't really know what traits are going to get passed along, and it takes a significant amount of time to get the desired results.  Enter Stage Left: Biotechnology!!

Thank you modern science and your understanding of gene sequences.  Plants that are genetically engineered are nothing short of a modern miracle, and I bet Gregor Mendel would have been doing cartwheels to see how this all worked (if monks do cartwheels).  Is this a perfect system?  Of course not, there is a great deal to learn about the process, but when we are looking at farming more effectively on less land and wanting to use less pesticides..  then GE is the way to go.

I found this article to be helpful, especially if you have some knowledge of genetics, genes, proteins and promoter sequences. The short answer is that it is a protein. What makes the protein? A gene has to be coded into the protein and the promoter is was signals transcription and translation of the gene in question. With Bt, the protein is not found in equal concentrations within the plant. The great concentrations are in the regions that the lepidoptera family likes to dine, namely the ears of the corn. By just targeting moths, bees aren't harmed. If you have been following colony collapse in our nation.. that is a big win for the honey bees. The less insecticidal agents we can use the better! The whole thing is super fascinating really. The moth larvae eats the corn, the Bt protein causes their guts to kinda "fall apart" and they become septic and die. Bad day for moths, good day for everybody else. Round up ready is a different trait..

 As far as "round up ready" corn, soy and cotton there is no round up "in" the plant as you asked earlier. It is also a genetically engineered trait that allows the plant to create an enzyme (protein) that allows the plant to continue to grow when the round up is applied. Round up denies the plant a similar amino acid that creates an enzyme that it needs to grow. I hope this helps some Here is an excerpt I found that explains how these plants work: Glyphosate tolerant crops

"The second major class of GMOs (mostly soy) have been engineered to be tolerant of the herbicide glyphosate (Roundup). Glyphosate is a small molecule that inhibits an enzyme, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), which catalyzes an essential step in the biosynthesis of the amino acids phenylalanine, tyrosine and tryptophan. By denying rapidly growing plants these amino acids, it is able to rapidly inhibit grown of plants onto which it has been sprayed. Glyphosate is generally considered to be inert in humans, who get these amino acids from their food, and do not have an EPSPS.

The obvious problem with using glyphosate to control weeds is that it will, under normal circumstances, also kill crop plants. However, plants that have been engineered to express an alternative form of EPSPS that functions normally even in the presence of glyphosate. These plants are thus “Roundup Ready“, and will survive doses of glyphosate used to kill weeds in the field.

Although the EPSPS gene used in Roundup Ready plants comes from a bacterium, the necessary changes could now easily be made to the plant’s own copy of EPSPS. Thus Roundup Ready crops, which produce no new proteins not found prior to genetic manipulation, shouldn’t really be places in the same class of GMOs as Bt expressing plants, which are expressing a new protein. And there is absolutely no reason to expect that there are any health risks associated with eating the altered form of EPSPS found in glyphosate resistant transgenic plants."
- See more at:

I hope this might be helpful to someone who is confused on the topic.