Cisgenic plants

1.       In your own words, but using the correct scientific terms, explain one method for producing a cisgenic plant.

A cisgenic plant is described as a crop plant that has been genetically modified with one or more genes isolated from a crossable donor plant [2].  It combines traditional techniques with modern biotechnology and dramatically speeds up the breeding process. This allows plant genomes to be modified while remaining plants within the gene pool. Therefore, cisgenic plants should not be assessed as transgenics for environmental impacts.

One method is electro-transfection, which is the application of strong electric field pulses to cells and tissue is known to cause some type of structural rearrangement of the cell membrane resulting in a temporary increase in porosity and providing a local driving force for ionic and molecular transport through the pores.[4]

2.       How is this process similar and how is it different from producing a transgenic plant?

Cisgenesis is described as specific alleles/genes in the breeder’s gene pool are introduced into new varieties without the accompanying linkage drag (co-transfer of DNA sequences that are linked to the gene of interest) which occurs in conventional breeding. In contrast, a transgenic plant receives gene(s) from a non-plant organism, or from a donor plant that is sexually incompatible with the recipient plant. [2].  

3.        How is the result of the cisgenic breeding process different from a classically bred plant? How is it similar?

In traditional breeding, obtaining desired traits is painstakingly slow and one challenge is the low affinity between wild and cultivated varieties. Techniques such as embryo rescues, cross bridges and somatic cell hybridization help overcome this obstacle. [2]

Compared with induced translocation and introgression breeding, cisgenesis is an improvement for gene transfer from crossable plants. The similarity of the genes used in cisgenesis compared with classical breeding is a compelling argument to translocation breeding, the insertion site of the genes is a priori unknown, as it is in cisgenesis. [1]

4.       What are the safety concerns of cisgenic plants? Are they different in transgenic plants? Are they different from classically bred plants?

Cisgenesis is not any different from traditional breeding or that which occurs in nature. There is no environmental risk evoked and release of cisgenic plants into the environment is as safe as that of traditionally bred plants, so they have the same hazards. However, the transformation techniques used in cisgenesis and transgenesis are the same, so they have similar risk linked to transfer technology. [2]

5.       In your opinion, is it correct to treat cisgenic plants like transgenic plants?

Now, cisgenic plants fall under regulations designed for transgenic organisms, possibly because there have not yet been any applications for the approval of the deliberate release of cisgenic plants into the environment [3] .

In my opinion, cisgenic plants are fundamentally different from transgenic plants, therefore they should be treated differently under GMO regulations.

Literature:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1525145/ [3]

http://www.ncbi.nlm.nih.gov/pubmed/17383037 [1]

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4127943/ [2]
http://scialert.net/fulltext/?doi=biotech.2008.385.402 [4]