Scientists find dingoes are genetically different from domestic dogs after decoding the genome | Wildlife

Dingoes are genetically distinct from domestic dogs and their evolution has been shaped by the Australian environment, say scientists who have fully decoded the dingo’s genome.

An international team of researchers analyzed the genetic make-up of a pure desert dingo called Sandy Maliki, and discovered that dingoes are an intermediate between wolves and domestic dog breeds.

Sandy, along with her sister and brother, were discovered when she was three weeks old in the central desert of Australia. In 2017, she won the “world’s most interesting genome” competition which funded DNA sequencing.

The researchers compared Sandy’s genome to that of five domestic dog breeds – a basenji, boxer, Labrador retriever, German shepherd and Great Dane – as well as a Greenland wolf.

Using five types of DNA sequencing technology, along with epigenetic analysis, the researchers found distinctions between the dingo’s genome and that of domestic dogs.

One was a difference in the number of copies of a gene coding for amylase, an enzyme that helps digest starches. Dingoes, like wolves, have only one copy of the amylase gene.

“Dogs, which have only emerged in the last 200 years, have between two and 20 copies of this gene,” said Matt Field, associate professor at James Cook University and first author of the study. “It is one of the telltale signs of domestication and [in dingoes] That is not here.”

The study’s lead author, Professor Bill Ballard, of La Trobe University, said that when humans first started domesticating dogs, they fed the animals rice products, which are high in starch. , creating selective pressure for dogs with multiple copies of the amylase gene. “Those dogs that did better with rice were… more likely to be associated with humans over time,” he said.

Ballard said some scientists had previously thought “the dingoes had lost the ancestral duplications of amylase.”

Sandy at three weeks old. Sandy is a pure desert dingo rescued as an abandoned pup by Barry Eggleton. Photography: Barry Eggleton

” That was not true. We could look at the genome signature and say, no, there was only ever one copy of amylase in the dingo, just like the wolf.

The difference could have important implications for conservation, Ballard said. “If a pure dingo eats very different things from a wild dog, then it’s going to have a different position in the ecosystem and…be differently attracted to different foods.”

The decoded dingo genome could also have veterinary applications for domestic dogs, Ballard said. He thinks it could be a genetic benchmark for canine diseases because “rather than another inbred dog you compare it to, you compare it to a healthy inbred animal.”

The team also analyzed dingo and German Shepherd droppings, finding differences in their microbiomes, including that the domestic dog had higher concentrations of three bacterial families involved in starch breakdown.

Dr Kylie Cairns from the University of New South Wales, who was not involved in the study, said microbiome differences could “explain why we don’t see feral dogs in Australia”. His previous research has suggested that most feral dogs killed across the country are pure dingoes or dog-dingo hybrids.

“[Dingoes] are older than the oldest domestic dog breed, which is the basenji. Their results clearly demonstrated that,” she said. “Dingoes are a wild canine that has been shaped by Australia’s climate and ecology over thousands of years.”

“The implications of this are that they should be treated like wild animals,” Cairns said. The dingo is “the only native animal that is baited and killed in national parks and conservation reserves” in Australia, she added.

“We have to respect their place as the apex predator in Australia because they have an important ecological role,” Cairns said. “We need to find a better way to co-exist with them so that we can have livestock farming – especially sheep – but still have dingoes in the environment.”

Scientists now plan to find out if the dingo has ever been domesticated, and also to sequence the genome of the Alpine dingo and the Fraser Island dingo. This will help them better understand interbreeding with dogs and what effect it might have on the animals’ behavior and role in the ecosystem, Field said.

The research was published in the journal Scientists progress.

Bette C. Alvarado