HOW ARE GM CROPS MADE?
1. Identify a trait of interest
The ultimate goal of genetic engineering is to introduce desired traits into organisms which do not naturally possess them. Once a particular trait has been chosen, scientists must then determine the proper organism that does possess the trait from which to extract genes from.
2. Isolate the gene of interest
By analyzing and comparing various genomes from organisms within the same species, the gene that codes for the desirable trait can be identified. After that, the gene is extracted using restriction enzymes. These proteins act as molecular scissors by cutting the strand of DNA at specific sites in order to isolate the target gene. A large variety of restriction enzymes can be created to recognize different types of nucleotide sequences, thus allowing only particular areas to be affected when using a single type of restriction enzyme.
3. Place the gene inside a transfer vector
A gene cannot simply be placed into a host. In order to penetrate the cell and integrate into the host’s genome, the gene must be carried by some sort of vector (i.e. bacteria).
4. Carry out the transformation
There are two primary methods for inserting a gene into a host (for plant purposes, a seed):
One is through the use of a gene gun. For this procedure, microscopic metal particles are coated with vectors containing the chosen gene and are then shot into the host’s cells.
The other method involves taking advantage of bacteria’s natural ability to invade cells. In this case, the chosen gene is inserted into a bacterium which is then allowed to infect a cell. The bacterium will insert its own DNA into the host cell, thus transferring the chosen gene into the seed.
5. Grow the GMO!
There is only one thing left to do in order to determine whether or not the genetically modified plant was a success --- to grow it! The hope is that the desired trait will appear in the newly grown plants, while at the same time displaying little to no complications.
Once deemed a success, biotech companies will make large investments in order to keep these plants alive, healthy, and reproducing. Many companies often use special climate-controlled growth chambers and a team of biologists to directly tend to the plants and make sure that they grow properly.
Check out the video below for an example of how one GMO (the papaya) was created.