Since the first cloned mammal, Dolly the Sheep, died abnormally young, much has been said about the aging of the clones. Now, scientists have cloned the world's first cloned dog in order to study these "re-clones" to determine if they die earlier and age faster than their non-cloned counterparts.
"Scientifically, this is very exciting," study author CheMyong J. Ko of the University of Illinois told Gizmodo. Ko pointed out that he is not the one who clones dogs, but offers consulting advice for the team in South Korea.
The details of the reproduction of the dog make them particularly difficult to clone. It was not until 2005 that scientists at the National University of Seoul announced that they had cloned a dog named Tai to create "Snuppy". Snuppy died shortly after her tenth birthday, two years younger than Tai and about two years younger than the average Afghan Hound.
Snuppy's lifespan was not markedly short, but you'll still remember Dolly, the first cloned sheep, that died abnormally fast. Many badumed that Dolly's death had something to do with her clone identity. New research has shown that it probably was not the case. But others still wonder if being a clone has an impact on life expectancy. Then the South Korean team cloned Snuppy to create the clones.
Researchers do not go into the details of the vital signs they will study in dogs, but Ko suggested that they could compare the immune system, genetics and behaviors between the three re-cloned and non-cloned animals.
"The clinical and molecular follow-up of these recruits during their lives will provide us with a unique opportunity to study the health and longevity of cloned animals compared to their cellular donors," according to the document recently published in Scientific Reports.
The team began taking 120 donor dog eggs, and then replaced the genetic material with Snuppy's. They implanted 13, 13 and 14 cells in three mothers, who reared four clones, but one died of severe diarrhea a few days after birth. Three different families have adopted or will adopt the other three, said Ko, one of the authors of the study. Sending dogs to three different homes will allow the team to see how other environmental factors can influence how clones age.
I asked Ko about the answer to the study; He said he had received both positive and negative comments. "People think that cloning will eventually be used for the supply of organs or tissue grafts," he said. "They think it's wrong to provide clones for those things because they could kill the clones." This is science fiction, of course, and scientists are working on other alternatives that still sound like science fiction, like the growth of organs from stem cells.
It is important to note that the researcher behind Snuppy, Woo Suk Hwang, was a controversial figure. The National University of Seoul dismissed him after investigations found that he had potentially falsified results in other experiments. This casts doubt on the authenticity of Snuppy, but later research found that Snuppy, at least, was actually a clone.
And now, more research on Snuppy reclons could shed light on what a clone really means.