Overview of the Process of Plant Genetic Engineering

8/7/2019 Overview of the Process of Plant Genetic Engineering

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Overview of the Process of

Plant Genetic Engineering

See

http://agbiosafety.unl.edu/education/summary.htm


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The Past

Traditionally, crop improvement was accomplished byselecting the best looking plants/seeds and saving themto plant for the next years crop.

Once the science of genetics became better understood,plant breeders used what they knew about the genes ofa plant to select for specific desirable traits. This type ofgenetic modification, called traditional plant breeding,modifies the genetic composition of plants by makingcrosses and selecting new superior genotype

combinations. Traditional plant breeding has been goingon for hundreds of years and is still commonly usedtoday.


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Limitations of Plant Breeding

First, breeding can only be done between two

plants that can sexually mate with each other.

This limits the new traits that can be added to

those that already exist in that species.

Second, when plants are mated, (crossed),

many traits are transferred along with the trait of

interest including traits with undesirable effects

on yield potential.


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Step 1: DNA extraction

DNA extraction is thefirst step in thegenetic engineeringprocess. In order to

work with DNA,scientists mustextract it from thedesired organism. Asample of anorganism containing

the gene of interest istaken through aseries of steps toremove the DNA.


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Step 2: Gene Cloning

During DNA extraction,all of the DNA from theorganism is extracted atonce. Scientists use

gene cloning to separatethe single gene ofinterest from the rest ofthe genes extracted andmake thousands of

copies of it.


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Step 3: Gene Design

Once a gene has beencloned, geneticengineers begin thethird step, designing the

gene to work onceinside a differentorganism. This is donein a test tube by cuttingthe gene apart with

enzymes and replacinggene regions that havebeen separated.


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Step 4: Transformation (gene

insertion) The new gene is inserted into some of the cells usingtechniques such as the gene gun, agrobacterium,microfibers or electroporation.

The main goal of each of these methods is to transport

the new gene(s) and deliver them into the nucleus of acell without killing it.

Transformed plant cells are then regenerated intotransgenic plants. The transgenic plants are grown tomaturity in greenhouses and the seed they produce,which has inherited the transgene, is collected.

The genetic engineer's job is now complete. He/she willhand the transgenic seeds over to a plant breeder who isresponsible for the final step.


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How to search for information on

terms you dont understand Lets Google gene gun

www.google.co.uk orwww.google.com

Type in using a gene gun Wikipedia is usually reasonably reliable

Check out 1 or 2 sites and make brief

notes


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Step 5: Backcross Breeding The final part of producing a

genetically engineered crop:Transgenic plants are repeatedlycrossed with elite breeding linesusing traditional plant breeding

methods to combine the desiredtraits of elite parents and thetransgene into a single highyielding transgenic line.

The result will be a plant with ayield potential close to current

hybrids that expresses the traitencoded by the new transgene.


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The Process of Plant Genetic

Engineering The entire genetic engineering process isbasically the same for any plant.

The length of time required to complete all five

steps from start to finish varies depending uponthe gene, crop species, available resources andregulatory approval.

It can take anywhere from 6-15+ years before a

new transgenic hybrid is ready for release to begrown in production fields.

Overview of the Process of Plant Genetic Engineering

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