Today NewScientist.com reported that the world’s first transgenic puppies were recently born in Korea. The five cloned beagles have been genetically modified to produce a fluorescent protein that glows red under ultraviolet light.
Lee and stem cell researcher Woo Suk Hwang were part of a team that created the first cloned dog, Snuppy, in 2005. Much of Hwang’s work on human cells turned out to be fraudulent, but Snuppy was not, an investigation later concluded.
A team led by Byeong-Chun Lee of Seoul National University in South Korea created the dogs by cloning fibroblast cells that express a red fluorescent gene produced by sea anemones.
Lee’s team states that the goal of the experiment is to create transgenic dogs to help model human diseases. Dogs are commonly used in comparative medicine studies. Humans and dogs share many physiological similarities and we suffer from a lot of the same diseases. The genetic bottlenecks common in purebred dogs combined with the terabytes of data obtained from the dog genome study have made studies on dogs vital in identifing genes that cause diseases in both species.
Lee’s team created Ruppy [short for ruby puppy] by first infecting dog fibroblast cells with a virus that inserted the fluorescent gene into a cell’s nucleus. They then transferred the fibroblast’s nucleus to another dog’s egg cell, with its nucleus removed. After a few hours dividing in a Petri dish, researchers implanted the cloned embryo into a surrogate mother.
Starting with 344 embryos implanted into 20 dogs, Lee’s team ended up with seven pregnancies. One fetus died about half way through term, while an 11-week-old puppy died of pneumonia after its mother accidentally bit its chest. Five dogs are alive, healthy and starting to spawn their own fluorescent puppies, Ko says.
Besides the low efficiency of cloning – just 1.7 per cent of embryos came to term – another challenge to creating transgenic dogs is controlling where in the nuclear DNA a foreign gene lands. Lee’s team used a retrovirus to transfer the fluorescent gene to dog fibroblast cells, but they could not control where the virus inserted the gene.
Creating transgenic dogs is difficult, expensive, time-consuming and highly controversial and the jury is still out on whether this work will lead to the development of viable laboratory populations or not. It’s not entirely new work. Ruppy and her kin aren’t the first fluorescent transgenic animals created in the laboratory. Scientists have already produced glowing bacteria, bollworms, fruit flies, mosquitoes, zebra fish, chickens, mice, rabbits, cats, pigs, cows – and even a monkey.
Fluorescence has become the standard marker in transgenic work because it gives scientists a simple way to verify that gene insertion was successful. The first flourescent transgenic animals were worms and bacteria created in at Columbia University in 1994. Thinkness writes:
These fluorescent creations, colorfully illustrating one of science’s hottest topics, are well tailored for consumption by the mainstream media. Eduardo Kac claimed to have created “transgenic art” by adopting a glowing rabbit, and his manipulated photos of the bunny he named Alba appeared in news stories around the world. The GloFish, which also borrowed its “Glo” from the jellyfish, drew similar attention when it went on sale last year as the world’s first transgenic pet.
Despite its absurd appearances, the glowing creature is a bona fide scientific revelation, one of genetic engineering’s most valuable tools. Researchers consistently rave about its performance as a transgenic marker. Moreover, they appreciate that it frees them just a bit from the most rigorous demands of research. All humans are, to some extent, natural scientists, relying heavily on sight to collect data from our environs. Professional scientists, however, must often overpower their eyes’ innocent observations with a relentless rationality. When working with fluorescent animals, they are able to act a little more like the rest of us, more like children playing with fireflies – they can once again goggle at something amazing, and know for a moment that seeing really is believing.
Kac’s kitschy art project and the idea of pet GloFish concern me. Given our human fascination with odd and unusual animals I’m more than a little concerned that if they become cheaper and easier to create, transgenic pets will become all the rage. In a world where many people lust for the biggest, smallest, most bizarrely marked or extremely built dogs – even when the traits that make these animals “special” come at a terrible cost – I’m afraid that glow-in-the-dark beagles could all too easily become the next yuppie status dog.
As for me – when I want to “goggle at something amazing” I’ll go watch the fireflies dance in the willows near the creek. And, ignoring of the whims of fashion, I’ll stick with the wonderfully unremarkable purpose-bred dogs I share my home with.