What are GMOs?

Ever seen a “non-GMO” or “bioengineered” label on one of your favorite foods? GMOs, or genetically modified organisms, are a mouthful to say and are a complex scientific, social and even legal topic. Purdue researchers have been studying GMOs since their invention and, through this educational website, shine a light on what’s in your pantry and beyond.

What is a GMO?

GMO stands for genetically modified organism, or, simply put, something living which has had its genetic code changed by humans. 

DNA, the molecule of the genetic code that provides a blueprint for life, exists in all plants, animals, fungi and bacteria. Scientists figured out how to read that DNA in the 1970s, but humankind experimented with it long before its existence was known.

For thousands of years, humans have domesticated other organisms for a variety of uses. To grow plants or raise animals with characteristics that best suited their lifestyle and environment, people selected and bred those that had the most beneficial and least undesirable traits. Whether it was wanting a crop to use less water or a sheep to produce more wool, plants and animals were bred over many generations until their DNA was optimized for what people most wanted.

Historically, this domestication and selection of traits was limited by which organisms could breed together. If you wanted a blue chrysanthemum, for example, there were no blue traits in chrysanthemums or other related flowers to breed it with. 

With the relatively recent understanding of the genetic code, scientists can now move or modify specific genes (DNA segments). With these new methods, flower breeders can take “blue genes” from a Canterbury bell flower and use it to produce a blue chrysanthemum. Though the process is much faster than traditional breeding, this GMO flower represents a similar, modern approach of humans adapting other living things to fill specific roles.

Are all GMOs plants?

Many different organisms are genetically modified for a variety of reasons. The first genetically modified organism was a bacterium modified with the gene of another bacterium in 1973. Bacteria are now one of the most important GMOs for society, as some are made to produce medicine like insulin and vaccines. 

Plants are often the first thing that comes to mind with GMOs, likely because plants are a huge part of daily life. GM plants have been created to improve crops and ornamentals alike: their growth, aesthetics, resource usage, nutrition, shelf stability, resistance to disease and pests, farmability and yield. In the U.S., these plants are major sources of material, food and biofuels.

More recently, animals and fungi have been genetically modified for food and for human health, including to grow organs for human transplants and to make meat and dairy safer for those with specific allergies.

GMOs are also used in research. A scientist might remove a gene from a plant in their lab, for example, to see how the plant grows without it. These studies tell us what genes do and why they are important. 

Although it is rare, and highly regulated, humans can also be genetically modified. In typical body cells, like the muscle or lung tissue, these modifications could be useful to prevent and cure disease, including cancer, through genetic therapy. Changing the DNA of reproductive cells is more controversial and strictly regulated, as it could be used to alter the physical appearance or health of children.

What do all the different GMO terms mean?

There are a lot of terms surrounding GMOs that may be used interchangeably, but they can have important distinctions:

GMO: Genetically modified organism. Something living which has had a specific part of its genetic code changed by humans. While it can refer to plants and animals that were domesticated through traditional breeding, it is more often used and legally defined as an organism with specific DNA modification by scientists.

Bioengineered: A new term often present on GMO food product labels. It refers to organisms with specific DNA modification by scientists, without potential reference to the earlier practices of traditional breeding.

Biotechnology, or genetic engineering: The processes by which GMOs are created other than traditional breeding.

Gene-editing: Gene editing is a specific form of genetic engineering where no new genes are added from a different species, but the genes naturally within an organism are altered.

Transgenic organism: An organism that contains DNA from another species.