Feline genetics helps identify the very first domestication of cats

Principal component analyzes (PCA) of genetic variation in random and wild felines. a PCA plot of SNP data (NOT = 983). b PCA plot of STR data (NOT=1861). A single dot represents an individual, the shape represents a geographical region, the color represents a geographical sub-region. The two feral cat populations are denoted by different colored squares. Middle Eastern, South Asian and Western European cats form the peripheral subpopulations of random breed cats. Wildcat hybrids and the island population of San Marcos, Baja California are additional peripheral populations for a and b, respectively. Credit: Heredity(2022). DOI: 10.1038/s41437-022-00568-4

Nearly 10,000 years ago, humans settling in the Fertile Crescent, the regions of the Middle East surrounding the Tigris and Euphrates rivers, first transitioned from hunter-gatherers to farmers. They have developed close ties to rodent-eating cats that conveniently served as ancient pest control in early civilizations of society.

A new study from the University of Missouri has found that this lifestyle transition for humans was the catalyst that sparked the world’s first domestication of cats, and as humans began to roam the world, they brought their new feline friends with them.

Leslie A. Lyons, feline geneticist and Gilbreath-McLorn Professor of Comparative Medicine at MU’s College of Veterinary Medicine, has collected and analyzed DNA from cats in and around the Fertile Crescent region, as well as throughout Europe , Asia and Africa, by comparing nearly 200 different genetic markers.

“One of the main DNA markers we studied was microsatellites, which mutate very rapidly and give us clues about recent cat populations and how breeds have changed over the past hundred years,” Lyons said. .

“Another key DNA marker we looked at was single nucleotide polymorphisms, which are single-base changes throughout the genome that give us clues to their ancient history many thousands of years ago. By studying and comparing the two markers, we can begin to piece together the evolutionary history of cats.”

Lyons added that while horses and cattle have witnessed various domestication events caused by humans in different parts of the world at various times, his analysis of feline genetics in the study strongly supports the theory that cats have probably first domesticated only in the Fertile Crescent before migrating. with humans all over the world. After feline genes were passed down to kittens from generation to generation, the genetic makeup of Western European cats, for example, is now very different from that of Southeast Asian cats, a process known as of “isolation by distance”.

“We can actually call cats semi-domesticated because if we let them loose in the wild, they would probably still hunt vermin and be able to survive and mate on their own due to their natural behaviors. “Lyons said. “Unlike dogs and other domesticated animals, we didn’t really change the behaviors of cats during the domestication process, so cats once again turn out to be a special animal.”

Lyons, who has studied feline genetics for more than 30 years, said studies like this also support his larger research goal of using cats as a biomedical model to study genetic diseases that affect both cats and humans, such as polycystic kidney disease, blindness and dwarfism. .

“Comparative genetics and precision medicine play a key role in the ‘One Health’ concept, which means that anything we can do to study the causes of genetic diseases in cats or how to treat their ailments can be useful for treat humans with the same diseases one day,” Lyon said.

“I’m building genetic tools, genetic resources that ultimately help improve the health of cats. When building these tools, it’s important to get a representative sample and understand the genetic diversity of cats around the world so that our genetic toolbox can be useful in helping cats all over the globe, not just in a specific region.”

Throughout his career, Lyons has worked with cat breeders and research collaborators to develop comprehensive feline DNA databases that the scientific community can benefit from, including feline genome sequencing of felines around the world. . In a 2021 study published in Trends in GeneticsLyons and his colleagues found that the cat’s genomic structure more closely resembles that of humans than that of almost any other non-primate mammal.

“Our efforts have helped stop the migration and transmission of inherited genetic diseases around the world, and an example is polycystic kidney disease, as 38% of Persian cats had this disease when we first ran our genetic test in 2004,” Lyon said. “Now that percentage has dropped significantly thanks to our efforts, and our overall goal is to eradicate genetic diseases from cats down the road.”

Currently, the only viable treatment for polycystic kidney disease has unhealthy side effects, including liver failure. Lyons is currently working with researchers at the University of California, Santa Barbara to develop a diet-based treatment trial for people with the disease.

“If these trials are successful, we may be able to get humans to try it as a more natural, healthier alternative to taking a drug that can cause liver failure or other health problems,” Lyons said. “Our efforts will continue to help, and it feels good to be a part of that.”

The new research was recently published in Heredity.