Yet another amazing similarity between humans and cats: the genome

Rats, the animals most used in laboratories, have a structurally chaotic genome. At some point in their evolution, mice shuffled their ancestors’ genomes like a deck of cards, upsetting the genetic makeup most mammals possess. Geneticist Bill Murphy from Texas A&M University shared: “I always consider them the greatest exception. They’re so different from any other mammal genome you can find, it’s like they’re from the Moon, and the others are from Earth.”

The mouse genome is still extremely useful. Thanks to years of careful research, detailed mapping and breeding of large populations, the researchers have decoded the mouse genome so thoroughly that they can make them young or old, or interfere on their carcinogenicity – findings that have important implications for humans. However, the different genomes of the mice make them less suitable for studies looking at how the human genetic code is packaged and stored. This is why some researchers have turned to other subjects, and surprisingly this “subject” is one level above the mouse in the food chain.

As it turns out, cats possess genomes that are surprisingly similar in both morphology and behavior to ours. According to feline geneticist at the University of Missouri, Leslie Lyons: “Apart from primates, cats and humans are among the most genetically similar.”, on genomic organization.

Lyons and Murphy, two of the world’s leading experts in feline genetics, have long been on a mission to build hierarchy in their somewhat small field of research. In addition to their genetic makeup, cats also live in the same house as us, as well as diet, have behavioral interactions, share many small insects, and several chronic diseases – including both problems and diabetes and heart. “If we could start to determine why those things happen to some cats, but not others.”, says Ms. Lyons, it is possible that both humans and cats could derive significant health benefits.

The cat’s gene sequence has now been solved from cover to book, with “a near perfect chain”, according to Ms. Lyons, something researchers have recently done with humans. Genome maps can become a valuable reference source for researchers. Investment in feline sequencing could pave the way for more precise treatment, as veterinarians can determine risk levels for a variety of diseases based on genetics and intervene at the earliest. maybe, “a diagnostic leap”, genetics expert Elinor Karlsson at the Broad Institute shared.

Since humans and cats share a number of diseases in common, it would be good for us to identify patterns of influence due to their genetic makeup. For example, cats can be affected by a neurological disorder such as Tay-Sachs disease in humans. A number of genetic therapies have proven effective in cats, and a research team is looking to apply these therapies to young children.

According to Lyons, the cat genetic code can also help us with basic science, because every cell in the body contains the same genome, only the developmental path is different. For decades, researchers have sought to untangle the mechanism of this process, where cells “force” certain genes into hibernation, and cause others to become active more frequently. One of the classic examples of this is the silencing of 1 of the 2 X chromosomes in female cells. New York University geneticist, Sud Pinglay, shared: “We still don’t fully understand why these genes can be ‘turned on and off’. This is a whole chromosome.”

The inactivation of the X chromosome is what gives the calico cat’s coat. These cats are nearly all female, with one of their X chromosomes containing the gene for orange fur, and the other black. With any given cell, only one of these two chromosomes is active. Deciding which chromosomes to work takes place very early in a cat’s development, and the new cells that separate, retain the selection of the “parent” cell, thereby creating large patches of color.

This property is so stable that, when the genome is transferred to other cells, their choice of which X chromosome to “turn on” remains the same. The first cloned cat, Carbon Copy, was genetically identical to its mother – a calico cat named Rainbow. But Carbon Copy has only brown and white feathers: apparently it was created from a dormant X-chromosome cell, and refuses to reverse the selection process. .

Many people will probably disagree with the study of cats in the laboratory. But according to Mr. Murphy, most manipulations in genetic research can be done fairly lightly. His team, for example, has become adept at extracting DNA from cat cheek cells, using only a stringed stick and then gently rotating it into the animal’s mouth.

Furthermore, there are significant benefits to working with popular pets: many often contribute directly or through veterinarians. When cats get sick, researchers can take samples, and in many cases make them healthy again. But Mr. Murphy said: “I think about 90% of the research on cats is done from cat diseases.”As for the cats that used to be in Mrs. Lyons’ lab, they will be adopted after they “retire” from scientific research.

Rats are easy to breed and inexpensive to keep in the lab, and of course they’re also top animals for scientific research. Cats will probably have a hard time surpassing mice in this area, when cats are still losing to dogs – animals that always cooperate with humans even in the laboratory. Cats are often more withdrawn and sadder than dogs in volunteering research. However, many experts still insist that cats have their own place with scientific research thanks to the undeniable benefits that studying them brings.