Almost every morning Guillaume Ramstein walks through the university park in Aarhus on his way to work. At this time of the year the old oak trees teem with bright green colors and the grass is covered in dandelions and daisies.
When he takes a seat in front of his monitor, he's ready to study the genes of plants. Not the plants in the beautiful park, but a little known grass called Brachypodium.
On his computer he looks through enormous amounts of data trying to find useful genes in the small plant. Genes that enable the plant to withstand longer periods of drought or higher temperatures.
The reason he's studying this little known plant and not wheat, barley or corn which we all know from trips to the countryside, is that Brachypodium is kind of like mice in pharmacological research.
"We call Brachypodium the mouse of cereals, because it works as a model organism to test new things on. Like the mice used in the medical sector, it's much easier to breed and genetically it's pretty similar to crops like wheat or barley," Ramstein explains.
"Because Brachypodium only has about 300 million letters in its DNA compared to 17 billion in wheat, it's also much cheaper and easier to sequence and work with."
By mapping the useful genes that make these plants better suited for climate change and a more plant based future, Ramstein and his colleagues are laying the foundation for both genetic modifications and traditional breeding.
The letters of the DNA
In the center of human, animal and plant cells there is a small core called the nucleus which contains our DNA.
Inside the nucleus the long two-stranded threads of DNA curl up and form the chromosomes. The threads are made up of nearly endless sequences of four small molecules, which we abbreviate A, C, G and T. People also call them the letters of the DNA.
It's the order of these letters that determine the function of our genes. Usually genes consist of thousands of letters, but a single wrong letter in the sequence may lead to both good and bad outcomes.
Whenever cells divide they need to copy all the genetic information. This process of copying sometimes goes wrong resulting in incorrect letters in the genome. Usually the cell corrects these errors but not always.
The same thing happens when a new plant or animal is conceived. During the mixing of the genes of the mother and father errors or new combinations may occur. These random variations are the mechanism for evolution.
Small genetic deviation makes a huge difference
Brachypodium is not the only plant Ramstein and his colleagues are studying. They also have a plant called Sorghum under their microscope.
Sorghum is the fifth most important cereal crop in the world in terms of production and harvested area. It's a tropical plant used for grain and for feeding animals, originally in Africa and Asia, but also in North America and Southern Europe.
In Sorghum they found a very useful genetic mutation, he explains. "We found a variant in a gene that does photosynthesis. Plants with an A instead of a G in this position seem to have a higher effectiveness when transforming sunlight into energy."
"This is important because the gene is similar in a lot of other crops. Our computer model suggests that the variation is also naturally present in species related to Sorghum such as maize and sugarcane."
Locating these small variations in the genome is laying the foundation for more targeted breeding. When the breeders know exactly which variations in the DNA to look for, it makes developing new crops adapted for a changing climate easier.
A foundation for new genomic techniques
When Ramstein and his colleagues at QGG find variations in crops they stop there—and there's a reason for that, he explains. "We publish our findings in academic journals and we collaborate with other research groups and the industry when they use our findings. Whether they use new genomic techniques like CRISPR or classical breeding."
Using new genomic techniques (NGTs) to edit crops is under strict regulation in the EU, but new legislation is on its way. Earlier this year the European Parliament voted to allow the use of NGTs in some cases. Moreover, scientists can already get a long way by introducing mutations by chemicals and other means, which are not under strict regulation under EU legislation.
As it is right now, NGTs are regulated by the same rules as GMO, but if the new legislation is passed in the European Council as well, it will allow for the use of NGTs in making genetic changes that could occur naturally in crops.
In other words it will enable the industry to use NGTs as a shortcut to getting the desirable traits in the crops. Traits that might take many generations of plants to achieve with traditional breeding methods.
And this is where Guillaume Ramsteins' research comes in. Many of his discoveries are mutations occurring naturally in other types of plants—like the variation in the Sorghum plant—and if the legislation is passed, the industry will be able to legally induce those mutations in popular European crops.
New Genomic Techniques (NTGs)
Since the early 2000s genomic technology has developed at a very fast pace. This has resulted in a lot of new techniques for editing the genome of plants and animals.
Overall these techniques can be put into two categories:
- Technologies that transfer genes from other organisms into the plant.
- Technologies that edit directly in the genome of the plant.
In 2012 Jennifer Doudna and Emmanuelle Charpentier discovered that CRISPR, a bacterial immune system, could be reprogrammed to edit anywhere in the DNA of humans, animals and plants.
CRISPR is one of several techniques to edit DNA, but has been the cheapest and most successful so far. With the new EU-legislation on NGTs, the technology is going to be important for the agroindustry.
Other technologies, like mutagenesis by chemicals or radiation, also introduce mutations in plant genomes, but they are not regulated by EU legislation and will remain important for the industry.
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