Tiny Pigs, Glowing Bunnies, and Pink and Purple Cats...Oh, My!

Jason Holley

A breakthrough in gene editing could herald an explosion of new species—and a brave new world of fanciful pets. 

Hercules and Tiangou, beagles both, were born at the Guangzhou Institutes of Biomedicine and Health last year, engineered to look like canine bodybuilders. The mutation didn’t fully take with Hecules, and he looks like any other beagle. But Tiangou, named after the mythological Chinese eater of the sun, has thickset limbs, as if she had been pumping iron in the womb. 

Their embryos were manipulated with a revolutionary gene-editing technology, CRISPR (short for “clustered regularly interspaced short palindromic repeats”—an acronym only a microbiologist could love). CRISPR allows scientists to easily make precise changes to DNA using enzymes originally discovered in bacteria. In the case of Hercules and Tiangou, the scientists deleted the myostatin gene, known to regulate muscle mass, thereby cutting the puppies’ limits on bulking up. 

It’s a strange time to be an animal. Bioengineered creatures that once were restricted to the lab are now poised to enter homes—starting with the dinner plate. Just last year, the U.S. Food and Drug Administration approved the commercialization of genetically engineered salmon that grow faster and larger than natural breeds. Meanwhile, a biotech startup called Recombinetics reengineered cows to have no horns to avoid the pain (for the animal) of removing them manually.

It was perhaps inevitable that such technol-ogies should trickle down to the pet industry, and just as inevitable that this should happen in China, where genetic engineers benefit from massive facilities and little oversight. The Beijing-based BGI, the world’s largest genome-sequencing company, announced plans last fall to sell micropigs, whose growth-hormone genes have been deleted so the animals grow only to the apartment-appropriate size of a corgi. If approved by the Chinese government, the micropigs will go on sale for $1,600 each.

The only genetically modified pets you can buy today are called GloFish, which contain genes from jellyfish and sea anemones, causing them to fluoresce. But labs are full of cats, rabbits, monkeys, and other animals engineered with this and other traits. (As a strange footnote in the history of animal engineering, in 2000, artist Eduardo Kac commissioned a glowing bunny from a French lab to take home as his pet. At the last minute, however, the lab refused to release it. Today, Kac continues to make protest art about the rabbit, whom he named Alba.)

Unless otherwise regulated, animal engineering will eventually find its way from the lab to consumer markets. Already, the U.S. biotech company ViaGen offers to clone the family dog for $50,000 (cats go for $25,000). How much more would owners pay for the ultimate luxury: an animal designed to specification? A zebra-striped hamster, say, or a teacup elephant? 

“Something that’s been of interest for a long time has been creating hypoallergenic cats, and if scientists can use CRISPR or some other genetic technique to do that, you can imagine an enormous market,” says Emily Anthes, science journalist and author of Frankenstein’s Cat: Cuddling Up to Biotech’s Brave New Beasts

In 2007, physicist Freeman Dyson predicted that manipulating DNA would one day become so easy that people would conceive a menagerie of new species. “De-signing genomes will be a new art form, as creative as painting or sculpture,” he wrote. Dyson foresaw children playing genetic games in which the winner “hatches the cutest dinosaur.”

Designer dinosaurs aren’t going to roam the Earth anytime soon, outside of the next Jurassic Park sequel. But Dyson touches on a basic urge to remake our environment—including the animals around us. It’s hard to pinpoint when humankind first started designing its pets. You might start 30,000 years ago, with the first identified bones of dogs that had smaller teeth and smoother foreheads than their wolf cousins. Charles Darwin based part of his On the Origin of the Species on his work with pigeon fanciers who bred traits, such as bulbous eyes, into birds, ostensibly for fun. Today’s biotechnology continues the work humans have been doing for millennia. 

But the sudden ease of editing the genome has raised a number of ethical debates in the scientific community—not least about whether to edit human DNA after perfecting the techniques on animals. “Almost all human therapies are based on our extreme confidence in our work on animals,” says George Church, a geneticist at Harvard Medical School. 

In December, scientists from around the world came together at the National Academy of Sciences, in Washington, D.C., to discuss the implications of using gene-editing technology on humans. The question being asked is where to draw the line. “Just like pharmaceuticals that are initially developed for medical reasons and then turn into playthings of students to give them an edge, the same can happen here,” says Church. Meaning the inventors of CRISPR have no control over how the technology will eventually be used. 

“As long as it’s safe and effective, it’s very hard to draw a line,” says Church. Until then, consider genetically edited animals as so many (glowing) guinea pigs.