What’s the deal with genetic modification?

Genetic modification is a major buzzword, and it’s one that’s seldom understood. Clare Garrard, a Biomedical Sciences Honours student at the University of Cape Town, explains what you need to know!

What‘s the deal with genetic modification? Via Science Accessibly

Genetic modification has both good and bad points, but I think it often gets a bad rap with no thought of the good it can do. What if you could save a thousand lives by being able to genetically engineer a vaccine into a staple food crop?
So let‘s start from basics. What exactly is genetic modification? Also known as genetic engineering, genetic modification ““ or GM -is the process of changing an organism‘s genetic makeup. Humans have been doing this indirectly for thousands of years through the process of breeding and selection, but the direct transfer of DNA from one organism to another only dates to the early 70s.

What are the advantages?

Since then, there have been thousands of advances using this technology. One of the best known is perhaps the advent of GM insulin. This was a breakthrough, as previously natural insulin had been collected from other animals, such as pigs or cows, and had caused adverse reactions in humans. It works by transferring the human insulin gene into a plasmid (transferable bacterial DNA) and then inserting this into bacteria that manufactures human insulin ““ with no adverse effects.

“Genetic modification ““ or GM -is the process of changing an organism‘s genetic makeup.”

This is one of the success stories of GM; Others include the originally controversial golden rice, which provides vitamin A; insect resistant Bt maize; and all of the scientific research possibilities that are opened up by this technology. For instance, a commonly used research method is to “œknock out“ genes ““ removing them ““ to prove that they have a certain function. This is useful in disease characterisation and the move towards treatment.

And the downsides?

Yet, for all its benefits, genetic modification is not perfect. One of the main objections is the fear that we don‘t know exactly what consequences our actions will have. These consequences include the possible effects of insect-resistant crops on non-target insects, as well as the possibility of gene flow (which is the natural transfer of genes between organisms).
Others question the safety of GM foods ““ some people think that GM food is unhealthy or causes cancer. However, each new genetically engineered crop variety undergoes extensive testing before it is approved for consumption. And in spite of a lot of bad press from anti-GMO activists, no harmful effects of GM crops to humans have been found to date. In fact, harmful effects have only been recorded for foods developed by conventional breeding methods.

“In spite of a lot of bad press from anti-GMO activists, no harmful effects of GM crops to humans have been found to date.”

This is likely due to the less exact nature of breeding versus genetic engineering. With breeding, you cross strains and multiple genes are combined in new ways, whereas with genetic engineering, usually only a handful of genes are introduced at clearly defined points in an organism‘s genome, resulting in a more predictable outcome.

How does it fit in with religion?

Another huge objection is religious ““ “œplaying God“. Although science is heavily regulated by ethics boards which enforce standards on experimental methods, Chinese teams have recently begun to genetically modify human embryos ““ taking us one step closer to the possible reality of designer babies. I can‘t say I personally am a fan of this extent of GM, but I have stopped to wonder ““ in Da Vinci‘s day autopsies were anathema.
It‘s a loaded subject, but I hope that helps to clarify things and bring some issues to light.

Looking to read further?

For more resources on genetic modification and its ethics, click here (and scroll to below the article). And if you‘re Googling, please be discerning and distinguish ideology from fact. Not everything the internet says is true.


Cyranoski, D. & Reardon, S., 2015. Chinese scientists genetically modify human embryos. Nature.
Jackson, D.A., Symons, R.H. & Berg, P., 1972. Biochemical method for inserting new genetic information into DNA of Simian Virus 40: circular SV40 DNA molecules containing lambda phage genes and the galactose operon of Escherichia coli. Proceedings of the National Academy of Sciences of the United States of America, 69(10), pp.2904““9.
Jones, R., 2012. Leonardo da Vinci: anatomist. The British journal of general practice“¯: the journal of the Royal College of General Practitioners, 62(599), p.319.
Katiraee, L., 2015. 10 studies proving GMOs are harmful? Not if science matters | Genetic Literacy Project. Available at: https://www.geneticliteracyproject.org/2015/11/13/10-studies-proving-gmos-are-harmful-not-if-science-matters/ [Accessed April 29, 2016].
Phillips, T., 2008. Genetically modified organisms (GMOs): Transgenic crops and recombinant DNA technology. Nature Education, 1(1), p.213.
Ronald, P., 2011. Plant genetics, sustainable agriculture and global food security. Genetics, 188(1), pp.11““20.

Have your say!

What are your thoughts on genetic modification? Be sure to let us know in the comments below, and be sure to keep up to date with Clare’s own thoughts on science at Science Accessibly!
Find Clare on LinkedIn