Scientists have developed a new technique, which could one day pave the way for the creation of a biological safety lock that would prevent genetically modified organisms (GMOs) from spreading into the wild and causing environmental damage.

The new technique includes inserting a built-in self-destructive mechanism into bacteria. The scientists have genetically recoded a strain of E. coli bacteria to depend on a synthetic amino acid that is not found in nature. The bacteria have to consume the nutrient in a specially created lab environment to survive. If they escape from a controlled lab setting, they would quickly die, scientists said in a pair of studies published in the journal Nature on Wednesday.

“We’re changing the whole genome,” George Church, a genetics professor at the Harvard Medical School and lead author of one of the studies, told the Boston Globe. “So all genes, including the ones involved in producing whatever chemical you’re interested in, all those genes get changed. None of these can go in or out functionally.”

GMOs have been used to produce various products, such as pharmaceutical proteins like insulin, various drug ingredients, dairy items and biofuels. Other than their uses, modified organisms also have the potential to upset natural ecosystems if they were to escape.

Scientists said in the studies that the use of the synthetic amino acid as a biological safeguard could one day help make genetically modified organisms safer in an open environment.

“This is the most radically altered genome to date in terms of genome function. We have not only a new code, but also a new amino acid, and the organism is totally dependent on it,” Church said in a statement.

Although the technique currently works in E. coli, it could theoretically be applied to more sophisticated organisms, such as plants. However, that application will take time due to technical limitations, according to scientists.

“The problem is that we cannot quickly determine if every single GMO that is produced is absolutely safe or absolutely unsafe to people and the environment,” Boston Globe quoted Karmella Haynes of the School of Biological and Health Systems Engineering at Arizona State University, who was not involved in the studies, as saying. “I feel that this research represents a step-change towards building reliable control switches for GMOs.”