December 12, 2009 by
Filed under veterinary nuclear medicine
Trent Consultants News: By Dan Vergano, USA TODAY. Scientists have cloned man’s best friend for the first time, creating a genetic duplicate of a 3-year-old male Afghan hound, South Korean scientists reported Wenesday.
Trent Consultants News: The puppy was born in April to its surrogate mom, a Labrador retriever. His name: Snuppy, short for Seoul National University puppy.
The team of scientists there that cloned the dog, led by Hwang Woo Suk, is the same one that first cloned human embryonic stem cells last year. Their achievement is reported in the journal Nature.
Researchers have cloned other animals, but dog cloning has posed a particular challenge. And the difficulties have alarmed some animal advocates and researchers.
The team created 1,095 embryos cloned from ear-skin cells of the hound and transferred them over two years into 123 female dogs. Only three pregnancies resulted: One ended in miscarriage, one puppy died after 22 days of pneumonia, and the last produced Snuppy.
Because dogs, unlike other mammals, ovulate immature eggs, the team had to remove eggs surgically from anesthetized dogs in heat. Only mature eggs are amenable to cloning, in which a skin cell is inserted into a hollowed-out egg, and the resulting combination is jolted with electricity to begin dividing like a normal embryo.
The “primary goal is to advance medical, including veterinary medical, understanding of disease causes and to accelerate stem cell research to the clinic,” report co-author Gerald Schatten of the University of Pittsburgh says.
Dog cloning has been controversial because it has long been the goal of some who want to replace beloved pets that way. Genetic Savings & Clone, a California firm that sells cloned cats for $32,000, heralded the advance in a statement. “We expect to provide cloning services to the owners of exceptional dogs around the world.”
Company officials said they expect to commercially clone a dog within a year using eggs collected from spaying procedures at veterinary clinics.
But biologist Martin Stephens of the U.S. Humane Society says, “We do have grave concerns.” He notes that millions of dogs await adoption in the nation’s animal shelters.
“Neither (the) results, nor we, support pet cloning,” Schatten says.
The American Anti-Vivisection Society, an animal rights group, released a statement calling for the regulation of pet cloning, saying, “The sole surviving puppy faces an uncertain future, as other cloned animals have been plagued by health complications resulting in their premature deaths.”
The cloner of Dolly the sheep renewed a demand for a worldwide ban on human reproductive cloning.
“Successful cloning of an increasing number of species confirms the general impression that it would be possible to clone any mammalian species, including humans,” said Ian Wilmut to The Associated Press. The reproductive biologist at the University of Edinburgh produced Dolly nearly a decade ago.
Dolly died prematurely in 2003 after developing cancer and arthritis.
The dog cloning team tried to distance its work from commercial cloning. “This is to advance stem cell science and medicine, not to make dogs by this unnatural method,” Schatten said to the AP.
Other scientists praised the South Korean team. “I think it’s incredible, just a statement of perseverance on their part, says Mark Westhusin of Texas A&M University
Like Dolly and other predecessors, Snuppy was created using a method called somatic cell nuclear transfer, or SCNT.
Scientists transfer genetic material from the nucleus of a donor adult cell to an egg whose nucleus — with its genetic material — has been removed. The reconstructed egg holding the DNA from the donor cell is treated with chemicals or electric current to stimulate cell division.
Once the cloned embryo reaches a suitable stage, it is transferred to the uterus of a surrogate where it continues to develop until birth.
Dog eggs are problematic because they are released from the ovary earlier than in other mammals. This time, the researchers waited and collected more mature unfertilized eggs from the donors’ fallopian tubes.
Snuppy was delivered by Caesarean section from his surrogate mother, a yellow Labrador retriever.
Schatten said the Afghan hound’s genetic profile is relatively pure and easy to distinguish compared to dogs with more muddled backgrounds. But dog experts said the researchers’ choice of breed choice was disquieting.
“The Afghan hound is not a particularly intelligent dog, but it is beautiful,” said psychologist Stanley Coren to the AP. Coren is the author of the best-selling manual “The Intelligence of Dogs.” He ranked the Afghan hound last among 119 breeds in temperament and trainability.
“Many people who opt for the cloning technique are more interested in fashionable looks,” he said to the AP. “Whenever we breed dogs for looks and ignore behavior, we have suffered.” The Associated Press contributed to this report.
Trent Consultants Dog Care and Training is all about helping pet owners enhance their relationships with their pets. Our professional pet-care services includes boarding, grooming, training, now available in Korea. When you’re at work, your dog can be playing and getting the attention he needs at Trent Consultants. Dogs that come for day care have opportunities to play throughout the day in one of our three fenced outdoor play areas with our doggie playgroups. You can visit us at www.trentconsultant.com. Email us info@trentconsultant.com.
Trent Consultants Dog Care and Training is all about helping pet owners enhance their relationships with their pets. Our professional pet-care services includes boarding, grooming, training, now available in Korea. When you?re at work, your dog can be playing and getting the attention he needs at Trent Consultants. Dogs that come for day care have opportunities to play throughout the day in one of our three fenced outdoor play areas with our doggie playgroups. You can visit us at www.trentconsultant.com. Email us info@trentconsultant.com.