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A new study could reveal exactly what makes orange cats special – though it may not be because of you.
Ginger kittens are known among cat owners because they are particularly friendly and fierce. However, for geneticists, the uniqueness of these houses stems from an unusual way. Scientists now say they have clarified a long -term mystery by determining a specific DNA mutation responsible for that golden shade – and the variant was not found in any other animal.
The genetic variant is first described on May 15. Published in the present biology.
“It’s a really unusual type of mutation,” said Christopher Kaelin, the main author of his studies, and senior genetics scientist at Stanford University in California.
The vast majority of completely orange cats are male, so scientists have led to the genetic orange code of the X chromosome a few decades ago. Like other mammals, women cats have two x chromosomes, and men have one x and one Y. any swollen cat with orange feature in one X chromosome will be completely orange. The woman will need to inherit the trait in both X chromosomes (one of her parents at a time) to be completely orange, which does less likely. Instead, most cats with orange fur have thin models – Calico or Tortoiseshell – which may include black and white.
Any where the X chromosome mutation exists and how it causes orange is still a riddle. Usually mutations that cause yellow or orange fur for animals (and red hair for humans) occur in genes that control color. And those genes are not carried to the X chromosome. “It suggested to us that we can learn something new and interesting by determining the molecular cause, which has turned out,” said Greg Bars, a senior researcher, a professor of genetics and pediatrics of Stanford.
Not only did the conclusions reveal the peculiar origins of some cats charismatic, but they also revealed new insights into the familiar gene.
Genetic deficiencies for orange cats
Women cats with an orange genetic code in one X chromosome will not be ginger. They will be a turtle shell (left) or “Calico”. – Laurie Laporte/Moment RF/Getty Images
The scientist has long been aware of this gender -related mutation; But the mutation itself perplexed geneticists. – Ping Shu/Moment RF/Getty images
The first step was to determine the genetic mutations specific to orange cats and can cause their color. For a decade, Kaelin attended cat exhibitions, asking for ginger -colored cat owners, whether he could take animal DNA samples for a cheek swab. (He is also interested in models similar to those found in wild cats such as leopards and ocelotics, which are common in popular breeds such as Bengal cats and toys.)
Comparing his DNA collection with cat genomes that have been followed over the last five to 10 years, he and his research team have identified the genetic variations of 51 x chromosome by orange men. However, 48 were also found in non -orange cats, which left three likely candidates for a rude mutation.
One of them was small, 5,076 pairs of bases, which removed about 0.005% in the X chromosome region, which did not appear to encode a certain protein. Deletion was not found in the gene where mutations are usually found. However, the mutation was among the two places associated with a nearby gene, known as the ARHGAP36, which regulates an important hormone alarm path used by almost all mammalian cells and tissues. The connection to pigmentation was not known. The gene is not even activated in pigment -producing cells.
To find out how the gene affects the color, Kaelin has examined his actions in live tissues collected in Spay and neutral clinics that would otherwise have been rejected. Experiments have shown that somehow the deletion activates the ARHGAP36 pigment cells, where it blocks the production of black pigment, causing cells to produce orange.
The option is not found in other animals, including wild cats that caused homemade cats.
“This is a genetic exception that has been spotted more than a hundred years ago,” said Kaelin in a press release from Stanford University. “This is definitely the comparative genetic puzzle that motivated our interest in gender -related orange.”
This exclusivity indicates that the mutation probably occurred once during domestication and then selectively bred selectively, said Kaelin. “We see the same mutation in all orange cats that we looked at in a wide geographical area, so one mutation took place,” he said. “And we know that the mutation is quite old, because Chinese art is depicted in the Calician cats dating back to the 12th century.” He added that prehistoric DNA professionals could use new data to determine exactly when and where the mutation originally came up.
“The established options could be valuable genetic measures of the population to trace the history of the evolution of internal cats,” said Hannes Lohi, a professor of veterinary BIOS and genetics at Helsinki University in Finland. Lohi did not participate in the study.
Meanwhile, Kaelin and his collaborators want to find out how small deletions that are not inside the gene can change the activity of a nearby gene.
“The goal is for sure that we will learn about a mutation,” Barsh noted, “but we also want to learn more about mutation mechanisms in general: why is it so unusual and the same mechanism can occur that causes other phenotypes to other animals? “He pointed out that there are many people who are thought to be genetic, but there was no genetic mutation that has been identified. Perhaps he claims that the problem is not only that we have not found mutations, but that we do not understand all the ways that mutations can first cause disease traits.
Would it be unusual to explain their personalities by Orange Cats genetics? To date, Kaelin says he and his colleagues have no reason to think so, although other researchers have been able to use the findings of the new study to seek the relationship between behavior and coat color. “I think orange cats have really convinced their owners that they are different, but they still have to convince us,” he said.
Amanda Schupak is a science and health journalist in New York.
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