Scientists are cloning animals for a number of possible future applications, the wilder of which include resurrecting extinct creatures.
Though cloning animals isn’t quite common or popular, it’s also not a new practice by any stretch of imagination. Its potential has been growing since the late 19th century, and scientists are eyeing up new possibilities that could shape the future in a number of ways.
Cloning animals: A brief history
Though most credit the sheep Dolly as the first cloned animal in 1996, an entire century prior a sea urchin was cloned in 1885 when German scientist Hans Driesch separated one embryonic cell and observed each half develop into two complete sea urchins.
The process was imitated successfully in 1905 by another Hans, embryologist Hans Spemann, who used the fine hair of his infant child to split a salamander embryo.
Nuclear transfer, the method by which a cell’s nucleus is transferred to an egg cell in order to grow a clone, was first successfully executed in the ‘50s, with frog embryos in 1952 and adult frogs in 1958.
Transfer of mammals’ early embryos was proven successful in the ‘80s with sheep and calves, and in 1996 Dolly the sheep became the first adult mammal cloned using somatic cell nuclear transfer, which takes adult DNA and resets it.
Since then, many other mammals including mice, cats, cattle, deer, dogs, horses, and more have been cloned as well.
Applications of cloned animals
So far, there are a number of practical applications for cloning animals being researched today. These include:
Cloning animals for medicine: Cloning test animals like mice creates a set of genetically identical subjects, which increases accuracy for various types of medical testing.
Cloning animals for agriculture: The FDA determined in 2008 that the meat and milk of cloned animals was just as healthy to consume as non-cloned versions. Though cloning is currently too expensive for this type of use, in the future animals with desired agricultural traits like lean meat and high protein may be cloned for consumption.
Cloning for pets: We’ve mentioned previously how the 9/11 dog hero Trakr was successfully cloned in 2009, resulting in five identical puppies. Pet owners could have their deceased pets cloned in theory — though copies often vary considerably from originals in both looks and personality.
Cloning animals for conservation: Despite the popular opinion that cloning ignores too many variables (such as environmental threats) to viably conserve threatened species, in 2001 an endangered wild sheep was successfully cloned.
Many scientists and conservationists still remain optimistic that it will become a powerful tool later on, and are collecting and storing DNA for if and when the time comes.
Mammoth recreations: While it’s distinctly unlikely that we’ll experience a Jurassic Park situation via dinosaur clones, the idea may not be as far out as it seems. An extinct mountain goat was cloned in 2009, though the kid died shortly after birth.
Before you yawn too much at goat-cloning, however, consider that frozen DNA from a wooly mammoth have given rise to speculation on eventual resurrection of the ancient beast, if not a mammoth hybrid. Scientists admit it is unlikely now, but could be possible in 50 years.
A long way to go
Despite a century in the making, cloning remains imperfect, and subject to ethical, scientific, and financial concerns.
Even today, the efficiency rate of animal cloning is not great, with Dolly, for example, being the only sheep born out of 277 cloned embryos.
According to the Humane Society, 99 percent of cloning attempts fail to produce a healthy animal, with few cloned animals born well enough to live a full lifespan.
Still, the possibilities are huge — mammoth, even — if the practice is perfected. How to use the power for good, rather than from a “because we can” mentality a la Frankenstein, is another story entirely.
Originally published on June 4, 2014.