Although controversial, genetically modified organisms (GMOs) can have a tremendous benefits in terms of preventing disease, fighting emerging "superbugs" and producing food. But a GMO that "escapes" its intended environment may end up wreaking havoc on the natural ecosystem. To combat this, a team at Rice University is developing a device, inspired by a Star Trek tricorder, that can scan water samples to detect the presence of GMO-associated proteins in the wild.
The researchers use the example of Bt-corn, a species of corn that's been modified to express the protein Bt delta endotoxin. This grants the vegetable a natural pesticide against European corn borer caterpillars, without harming most other insects and animals — including humans.
"It's a wonderful invention that lets us produce more corn per unit area," explains Scott Egan, lead researcher on the project. "But then that corn and the detritus — the leaves, stems and roots — get into the creek system. And lo and behold, a very close relative to the herbivores that attack the corn is the caddisfly, which lives within the aquatic system."
As useful as that protein is in controlled environments, concentrations of it in creeks and waterways could have a negative impact on caddisflies, which in turn could disrupt the entire aquatic ecosystem. To minimize that harm, the project aims to study what effects GMOs can have on natural systems, as well as develop ways to detect their presence and concentration.
"It's meant as a tool that can be used in any situation to detect and quantify, and get that information back to the stakeholders in the field or Department of Natural Resources folks who care about whether certain chemicals are floating around," says Egan.
Trekkies will remember the tricorder, a device used by the Enterprise crew to scan and analyze alien worlds and lifeforms. The team says the Star Trek gadget inspired them to develop their own device called a light transmission spectrometer (LTS), which currently detects proteins that indicate the presence of GMOs, and soon will be able to determine their quantity too.
The LTS works by binding nanoparticles to target DNA or antibodies to proteins from GMOs – be they plants or animals – which allows them to be detected and quantified. Currently, the device can detect the target DNA if it's present at a concentration of 50 copies per milliliter of water, but the team hopes to get that down to about three copies per milliliter, which is something other lab-based methods can manage.
To put the LTS through its paces, the researchers will test it in a series of controlled environments with increasing complexity, beginning in paddling pools, then moving up to synthetic streams and fully modeled aquatic ecosystems complete with creeks, ponds and wetlands.
The team says that eventually the device's ability to detect low concentrations of DNA could even be used by scientists searching for life beyond Earth, by studying extraterrestrial samples for signs of the building blocks of life.
Source: Rice University
