Grasses steal genetic secrets from other species to speed up evolution

According to a new study, grass crops can bend the laws of evolution by borrowing genes from their neighboring species, thus gaining a competitive benefit.

Grass Crops. Image Credit: biletskiyevgeniy.com/Shutterstock.com

A study, headed by the University of Sheffield, has now demonstrated for the first time that grasses can integrate DNA from other organisms into their genomes through a process, called lateral gene transfer.

The hijacked genetic secrets provide the grasses with an evolutionary benefit by enabling them to grow bigger, stronger, or faster, and also adapt to new environments more quickly. These results could guide upcoming studies to produce crops that are more resistant to the impact of climate change and help address food security issues.

The team from the University of Sheffield looked at grasses, which comprised some of the most ecologically and economically valuable plants, like rice, barley, wheat, and maize, which are widely grown around the world.

Grasses are taking an evolutionary shortcut by borrowing genes from their neighbors. By using genetic detective work to trace the origin of each gene, we found over 100 examples where the gene had a significantly different history to the species it was found in. The findings may make us as a society reconsider how we view GM technology, as grasses have naturally exploited a very similar process.”

Dr Luke Dunning, Study Senior Author, Department of Animal and Plant Sciences, University of Sheffield

Dr. Dunning continued, “If we can determine how this process is happening it may allow us to naturally modify crops and make them more resistant to climate change. What we are seeing is not hybridization, but the consequences are similar. Lateral gene transfer can move genetic information across wider evolutionary distances, which means it can potentially have even bigger impacts.”

“Whilst only a relatively small proportion of genes are transferred between species, this process potentially allows grasses to cherry-pick information from other species. This likely gives them huge advantages and may allow them to adapt to their surrounding environment quicker,” added Dr. Dunning.

We still don't know how this is happening or what the full implications are. But, we know it is widespread in grasses, a family of plants that provide a majority of the food we eat. We detected foreign DNA in a wide range of grasses with all kinds of life-history strategies indicating it is not restricted to those with a specific trait. However, we did detect a statistical increase in species which possess certain kinds of modified stems called rhizomes.”

Samuel Hibdige, Study First Author and PhD Researcher, University of Sheffield

Since the Darwin period, people’s understanding of evolution has been largely based on the belief that common descent is the rule of animal and plant evolution, with genetic data passed down from parents to offspring.

The next steps of the team is to find out the biological mechanism behind this phenomenon and to explore whether this is a continuous process in crops that plays a major role in the variations seen between different crop varieties.