Feb 17, 2022Unintended effects of gene editing in tomatoes studied
Yi Li, professor of plant science in the University of Connecticut College of Agriculture, Health, and Natural Resources is working on a new $500,000 Biotechnology Risk Assessment Research Grant from the USDA/NIFA to study a genetic editing technique in tomato plants.
Genetically engineered organisms are becoming increasingly popular given their potential applications to improve the food supply. Gene editing allows scientists to manipulate an organism’s DNA, leading to produce that stays fresher longer, resists pests and viruses, or has higher nutritional content.
One common method of gene editing is manipulating DNA methylation. DNA methylation is the process by which methyl groups are added to a DNA molecule. This changes the activity of that DNA segment without changing the DNA itself. Methylation can suppress or promote the expression of certain genes and the proteins they code for.
This promising gene editing technique could improve crops on a large scale. However, the potential unintended side effects of this process are not well-studied, hindering its potential agricultural applications.
Tomatoes are one of the most popular forms of produce, making them an excellent candidate for potential gene editing enhancements. Furthermore, tomato quality and attributes are highly influenced by DNA methylation events.
Li will specifically look at CRISPR/dCas-mediated DNA methylation in tomatoes. Research on this technique has shown there are some off-target effects, or methylation changes to parts of the genome scientists were not intentionally changing. But no one has yet characterized what these effects are, creating a significant knowledge gap Li is now looking to fill.
Li will compare this methylation technique to genetic transformation, another gene editing technique. Genetic transformation differs from DNA methylation because it involves introducing foreign DNA into the plant’s genome, rather than working on changing the expression of its own. Li will compare these two gene editing techniques to more conventional growing techniques without gene editing.
Li will examine the DNA methylation, RNA sequences, fruit quality, and other observable characteristics for each method. This work will directly address the Biotechnology Risk Assessment Research Grant (BRAG) Program’s priority to gain information about the types and frequencies of nucleic acid changes various genetic engineering techniques introduce into important crops, like tomatoes.
This work will also support the BRAG program goal of providing regulatory agencies with knowledge to make scientifically informed decisions regarding genetically engineered organisms to protect consumers and the environment. This aspect of the project will be largely carried out by co-principal investigator, Stacey Stearns. Stearns is a communications specialist in UConn Extension.
“The knowledge generated from this study will aid plant breeders practicing DNA methylation editing in crops and facilitate the policy- and decision-making process at federal regulatory agencies,” Li says.
Li’s project includes a public education component. Li and his team will create and share articles, websites, videos, and presentations with the general public.
This outreach will help the public better understand gene editing technology and its applications for agriculture. Education about genetic engineering can help dispel misinformation and misunderstandings about gene editing.