The world’s first wolf clone birthed by a surrogate dog has been revealed by a Chinese pet-cloning company, an achievement paving way for cloning endangered species.
The Sinogene Biotechnology Company, based in Beijing, unveiled the cloned female wolf pup, named Maya, and her beagle mother on a brief video at a press conference held on September 19th.
According to Sinogene representatives, the cloned wolf was born on June 10th in a laboratory in Beijing, and the video was released a hundred days after its birth.
Sinogene predominantly specializes in cloning dead pets, such as cats, dogs, and horses, for private clients although it now wants to use its expertise to help clone endangered species for conservation purposes, reports indicated.
Maya, the wolf, was cloned using DNA collected from a fully grown Arctic wolf, also named Maya, that died in captivity at Harbin Polarland, a wildlife park in northeast China.
According to reports, the original Maya, who was born in Canada before being shipped to China in 2006, died due to old age in early 2021.
Wolf born to surrogate dog through somatic cell nuclear transfer
During the company’s press conference, Mi Jidong, general manager of Sinogene, said the cloning of Maya was successfully completed “after two years of painstaking efforts.”
Sinogene researchers originally created 137 Arctic wolf embryos by fusing skin cells from the original Maya with immature egg cells from dogs, using a process known as somatic cell nuclear transfer (SCNT).
Out of the 137 embryos, 85 were successfully transplanted into seven beagle surrogates, and from the transplanted embryos, just one fully developed during pregnancy, reports further indicated.
Beagle surrogates were used by researchers because there were not enough female wolves in captivity for the studies. Luckily enough, however, dogs share enough DNA with wolves for the hybrid pregnancy to gestate successfully.
The cloned wolf now lives with her surrogate dog mother at a Sinogene lab in Xuzhou in eastern China, but she will eventually be transferred to Harbin Polarland to live with other Arctic wolves.
However, Maya will have to slowly be introduced to the rest of the pack because of her isolated upbringing, Harbin Polarland Park keepers noted.
Chinese company revealed another wolf clone using DNA
The Chinese company, Sinogene, also revealed that a second Arctic wolf cloned using DNA from an unknown male, was due to be born on Thursday, September 22nd. However, there have been no confirmed reports thus far of the pup’s birth.
According to reports by Chinese media agencies, the company also announced a new partnership with the Beijing Wildlife Park to clone more captive species in the future, although no specific projects have yet been announced.
Sinogene was also involved with a project that produced six identical German shepherd clones in 2019, which were then inducted into the Beijing police force, according to international press.
Scientists from a U.S. based non-profit conservation organization, Revive & Restore, successfully cloned an endangered black-footed ferret (Mustela nigripes) in 2020.
That same year, the company also successfully cloned an endangered Przewalski’s horse (Equus przewalskii), and company technicians are now attempting to revive the extinct passenger pigeon (Ectopistes migratorius) using the cloning process.
Relevance of Cloning endangered species like Maya, the wolf
Ben Novak, lead scientist at Revive & Restore, said the main benefit of cloning endangered species is that it maintains the amount of genetic diversity within a species.
“Cloning is a drastically underutilized tool, [but] in the future, it could be a literal lifeline for species that become rarer or worse, go extinct,” Ben Novak said in an email to Live Science.
If the clones can reproduce with other non-cloned individuals, this gives threatened species a fighting chance to adapt to the selection pressures that are driving them towards extinction, he added.
Novak identified another benefit of cloning, namely that it can be utilized in conjunction with existing captive-breeding programs, especially when surrogate mothers from other species are used.
Rather than taking animals from the wild to create a backup population in captivity, scientists can take genetic samples from wild animals and create clones in the lab using more readily available surrogates, as they did with Maya and her beagle mother.
These genetic backups can then be introduced into the wild to replenish struggling populations, Novak said.
“For mammals, it appears that two species must share a common ancestor less than 5 million years ago” for the surrogate pregnancy to be successful, Novak revealed. This opens up the possibility of reviving extinct species by using closely related living surrogate species, he added.
Limitations to cloning other animals like the recent wolf clone
Although considerable success was witnessed in previous cloning attempts, one of the main issues is that not all animals can be successfully cloned yet.
Scientists have noted that to date, only mammals, fish, amphibians, and a single insect species have been cloned using SCNT, Novak said. For birds, reptiles, and egg-laying mammals, such as platypuses and echidnas, SCNT does not work because the eggs do not properly develop, he added.
According to Novak, compared with artificial insemination or in-vitro fertilization, cloning also has a very low success rate.
As with Maya the wolf pup, researchers often have to create hundreds of embryos and successfully implant them in multiple surrogates for just one animal to be born. This makes cloning an expensive process.
Due to these high costs, the emergence of private entities such as Sinogene and Revive & Restore will likely play a key role in the future of conservation cloning. Historically, most cloning research has been done by universities that are underfunded, Novak said.
Therefore, “the partnership of for-profit companies with conservation programs is key to turning cloning from a seldom-researched technique into a valuable conservation tool.”
“It’s great to see more wildlife cloning work being done, [and] I hope all these recent achievements in cloning show the world that cloning is ready to use as a beneficial tool for wildlife conservation,” Novak said.
Cloning advocates recognized that the birth of Maya is another step in the right direction for this area of research.