12 Bizarre Examples of Genetic Engineering

Banana Vaccines

People may soon be getting vaccinated for diseases like hepatitis B and cholera by simply taking a bite of banana. Researchers have successfully engineered bananas, potatoes, lettuce, carrots and tobacco to produce vaccines, but they say bananas are the ideal production and delivery vehicle.

When an altered form of a virus is injected into a banana sapling, the virus’ genetic material quickly becomes a permanent part of the plant’s cells. As the plant grows, its cells produce the virus proteins—but not the infectious part of the virus. When people eat a bite of a genetically engineered banana, which is full of virus proteins, their immune systems build up antibodies to fight the disease—just like a traditional vaccine.

Enviropig

The Enviropig, or “Frankenswine,” as critics call it, is a pig that’s been genetically altered to better digest and process phosphorus. Pig manure is high in phytate, a form of phosphorus, so when farmers use the manure as fertilizer, the chemical enters the watershed and causes algae blooms that deplete oxygen in the water and kill marine life.

So scientists added an E. coli bacteria and mouse DNA to a pig embryo. This modification decreases a pig’s phosphorous output by as much as 70%, making the pig more environmentally friendly.

Fast-Growing Salmon

AquaBounty’s genetically modified salmon grows twice as fast as the conventional variety. The company says the fish has the same flavor, texture, color and odor as a regular salmon, and can help address overfishing problems. However, the debate continues over whether the fish is safe to eat or good for the environment.

Genetically engineered Atlantic salmon has an added growth hormone from a Chinook salmon that allows the fish to produce growth hormone year-round. Scientists were able to keep the hormone active by using a gene from an eel-like fish called an ocean pout, which acts as an “on switch” for the hormone.

Some opponents are concerned that if this fish were ever to escape or be introduced into ecosystems, it might be about outcompete native species and become invasive.

The FDA approved the sale of the salmon in the U.S. in 2015, marking the first time a genetically modified animal was approved for sale in the U.S.

‘Flavr Savr’ Tomato

The Flavr Savr tomato was the first commercially grown genetically engineered food to be granted a license for human consumption. By adding an antisense gene, the California-based company Calgene hoped to slow the ripening process of the tomato to prevent softening and rotting, while allowing the tomato to retain its natural flavor and color.

The FDA approved the Flavr Savr in 1994; however, the tomatoes were so delicate that they were difficult to transport, and they were off the market by 1997. On top of production and shipping problems, the tomatoes were also reported to have a very bland taste: “The Flavr Savr tomatoes didn’t taste that good because of the variety from which they were developed. There was very little flavor to save,” said Christ Watkins, a horticulture professor at Cornell University.

Genetically Modified Trees

Trees are being genetically altered to grow faster, yield better wood and even detect biological attacks. Proponents of genetically engineered trees say biotechnology can help reverse deforestation while satisfying demand for wood and paper products. For example, Australian eucalyptus trees have been altered to withstand freezing temperatures, and loblolly pines have been created with less lignin, the substance that gives trees their rigidity.

However, critics argue that not enough is known about designer trees’ effect on their natural surroundings—they could spread their genes to natural trees or increase wildfire risk, among other drawbacks. Still, the USDA gave approval in May 2010 for ArborGen, a biotechnology company, to begin field trials for 260,000 trees in seven southern states.

Glow-in-the-Dark Animals

In 2007, South Korean scientists altered a cat’s DNA to make the animal glow in the dark and then took that DNA and cloned other cats from it, creating a set of fluffy, fluorescent felines. Here’s how they did it: The researchers took skin cells from Turkish Angora female cats and used a virus to insert genetic instructions for making red fluorescent protein. Then they put the gene-altered nuclei into the eggs for cloning, and the cloned embryos were implanted back into the donor cats—making the cats the surrogate mothers for their own clones.

Earlier research in Taiwan resulted in three pigs that glowed fluorescent green. Wu Shinn-chih, assistant professor for the Institute and Department of Animal Science and Technology of National Taiwan University (NTU), is shown with one of the pigs in the photo above.

What’s the point of creating a pet that doubles as a nightlight? Scientists say the ability to engineer animals with fluorescent proteins will enable them to artificially create animals with human genetic diseases.

Less Flatulent Cows

Cows produce significant amounts of methane as a result of their digestion process; it’s produced by a bacterium that’s a byproduct of cows’ high-cellulosic diets that include grass and hay. Methane is a major contributor—second only to carbon dioxide—to the greenhouse effect, so scientists have been working to genetically engineer a cow that produces less methane.

Agriculture research scientists at the University of Alberta have identified the bacterium responsible for producing methane and designed a line of cattle that creates 25% less methane than the average cow.

Medicinal Eggs

British scientists have created a breed of genetically modified hens that produce cancer-fighting medicines in their eggs. The animals have had human genes added to their DNA so that human proteins are secreted into the whites of their eggs, along with complex medicinal proteins similar to drugs used to treat skin cancer and other diseases.

What exactly do these disease-fighting eggs contain? The hens lay eggs that have miR24, a molecule with potential for treating malignant melanoma and arthritis, and human interferon b-1a, an antiviral drug that resembles modern treatments for multiple sclerosis.

Pollution-Fighting Plants

Scientists at the University of Washington are engineering poplar trees that can clean up contamination sites by absorbing groundwater pollutants through their roots. The plants then break the pollutants down into harmless byproducts that are incorporated into their roots, stems and leaves or released into the air.

In laboratory tests, the transgenic plants are able to remove as much as 91% of trichloroethylene—the most common groundwater contaminant at U.S. Superfund sites—out of a liquid solution. Regular poplar plants removed just 3% of the contaminant.

Super Carbon-Capturing Plants

Humans add about nine gigatons of carbon to the atmosphere annually, and plants and trees absorb about five of those gigatons. The remaining carbon contributes to the greenhouse effect and global warming, but scientists are working to create genetically engineered plants and trees that are optimized for capturing this excess carbon.

Carbon can spend decades housed in the leaves, branches, seeds and flowers of plants; however, carbon allocated to a plant’s roots can spend centuries there. Therefore, researchers hope to create bioenergy crops with large root systems that can capture and store carbon underground. Scientists are currently working to genetically modify perennials like switchgrass and miscanthus because of their extensive root systems.

Venomous Cabbage

Scientists have taken the gene that programs poison in scorpion tails and looked for ways to combine it with cabbage. Why would they want to create venomous cabbage? To limit pesticide use while still preventing caterpillars from damaging cabbage crops. These genetically modified cabbages would produce scorpion poison that kills caterpillars when they bite leaves—but the toxin is modified so it isn’t harmful to humans.

Web-Spinning Goats

Strong, flexible spider silk is one of the most valuable materials in nature, and it could be used to make an array of products—from artificial ligaments to parachute cords—if we could just produce it on a commercial scale. In 2000, Nexia Biotechnologies announced it had the answer: a goat that produced spiders’ web protein in its milk.

Researchers inserted a spiders’ dragline silk gene into the goats’ DNA in such a way that the goats would make the silk protein only in their milk. This “silk milk” could then be used to manufacture a web-like material called Biosteel.