Tag: gene editing

Why Creating ‘Hypoallergenic Cats’ With Gene Editing Is A Bad Idea

On paper, the promise of “hypoallergenic cats” sounds great.

For the first time, people who love cats but are allergic to the furry little guys would be able to open up their homes to them. More cat lovers and more homes for cats is always a good thing, right?

Maybe not in this case.

The quest to create cats who do not trigger allergies depends on CRISPR gene editing, a method that allows scientists to edit, delete and replace sections of the genome. In this case, Virginia-based biotech company InBio wants to edit the genome of domestic felines to block Fel d 1 (Felis domesticus allergen I), a protein produced in cat saliva and in tiny subdermal exocrine glands, which secrete the protein via the same ducts that allow a cat’s fur to grow out from its skin.

Since cats are fastidious neat freaks and groom themselves constantly, the Fel d 1-carrying saliva is applied to their coats several times a day. When it dries, it contaminates a cat’s living space by flaking off the fur as dander or by shedding.

That’s why people who are allergic to cats can suffer symptoms like sneezing, itching and watery eyes not only from petting them, but also from spending time in homes where cats live.

What does Fel d 1 do, and why do cats need it?

The problem is that no one knows why cats produce Fel d 1 and what purpose it serves. Other proteins, like Fel d 4 found in pheromones and Fel d 2, help cats communicate by scent and prevent certain fluids from leaving the bloodstream, respectively.

Take a look at this quote from Nicole Brackett, a geneticist at InBio: (The emphasis on certain words is ours)

“The gene sequences don’t appear to be that well conserved over the course of evolution, which suggest things about whether or not the gene is essential,” Brackett told BioSpace, a life sciences publication. “An essential gene, one that would be required for survival or viability, generally doesn’t change much over evolution, and we’re seeing change between the exotic and domestic cat that suggests that maybe those sequences are not conserved, and maybe the protein is not essential.”

While we understand scientists have to be circumspect, especially regarding research that breaks new ground, that’s a lot of hedging and a lot of uncertainty. (It’s also not clear if Brackett is comparing domestic feline Fel d 1 levels to wild cats — felis sylvestris and lybica — wild felids in general, or hybrids like Bengals and Savannah cats, which are more commonly called exotics.)

cute cat lying on pillow
Credit: cottonbro/Pexels

The team members developing the allergen gene edit assume Fel d 1 doesn’t have a critical function because individual domestic cats and other species of felids may produce different quantities of the protein.

But that’s a huge assumption, and it’s also presumptuous to assume we humans would know whether the gene edits have a major impact on felines. After all, we still don’t always know when cats are in pain or the reasons for many of their behaviors, and we don’t know what sort of cascade effect can be triggered by shutting down the production of a protein.

The race to make cats hypoallergenic

Companies see a huge opportunity for profit in the cat allergy alleviation market. Last year, Purina announced to much fanfare the availability of a new kind of cat food the company claimed would drastically reduce allergens after about three weeks of putting kitties on the new grub.

The claims haven’t been independently verified, and most press coverage is either credulous or consists of marketing masquerading as news coverage, like this advertisement from Purina that is presented like a news story in USA Today.

Back when a company called HypoCat announced it had conducted successful trials of a “vaccine” that would “neutralize’ Fel d 1, we spoke with immunologist Kamal Tirumalai, who pointed out that humans making such profound changes to companion animals for the sake of human convenience “passes neither the scientific nor the moral smell test.”

Like others, Tirumalai said she worried about unintended consequences.

“A vaccine given to cats to reduce their allergenicity for humans burdens them unnecessarily when human allergy to cats is primarily a human problem and should have a human solution in the form of reducing people’s cat allergies,” Tirumalai told PITB at the time. “Cats are perfect as they are. Why should they be the ones forced to change in order to be accommodated by a human whose immune system happens to have a problem with one of their proteins? This solution just doesn’t pass the moral smell test.”

HypoCat uses an injection to “induce anti-Fel d 1 antibodies in the cat,” while the CRISPR technique would snip the relevant DNA out entirely.

Buddy
“Come now, let us not be absurd. Do you really think a designer kitten could be as handsome as I am?” Credit: Big Buddy

So far, Brackett and her colleagues have deleted one of two cat cells that produce Fel d 1 in samples in a petri dish, and have not made any changes to live animals. The experiments yielded a “55 percent knockout rate” for the Fel d 1 allergen, Brackett said, “which we were really happy with.”

Designer kittens: Gattaca for cats

If subsequent attempts are successful and the company sees commercial promise in editing feline genes, the process could be used to create “designer kittens” or to alter the genomes of existing cats. Brackett told Smithsonian magazine that the goal is to accomplish the latter.

But if it turns out the edits don’t work for existing cats, or the designer kitten trend becomes a thing, there’s another major moral concern similar to the objections to cat cloning. If people buy designer kittens, they’re not opening their homes to the millions of cats who need them.

Manipulating feline DNA isn’t a novel idea. A decade ago, a research team spliced genes from jellyfish using a different method to create cats who glow in UV light as part of a study into feline immunodeficiency virus (FIV).

Ultimately it comes down to what we’re willing to do for the sake of our own convenience. At a time when declawing has finally been outlawed in two states and dozens of cities, and people are more conscientious than ever with regard to their pets, do we want to risk their health so we don’t have to pop a few Benadryl?

The Mixed Legacy of CC the Cloned Cat

Like Dolly the sheep, CC the cat’s arrival into this world was accompanied by apocalyptic pronouncements, grave concerns about man’s hubris at playing God and warnings that human clones wouldn’t be far behind.

At the time cloning was revolutionary, something that was only supposed to exist in science fiction movies. Most people were uneasy with it, and much of the public debate centered around ethical concerns.

It was 2001: The world had just gotten over the Y2K scare, the Sept. 11 attacks and an abundance of turn-of-the-century, end-of-the-world prophesies. When people thought of cloning, they pictured tyrannosauruses rampaging through Jurassic Park and Jeff Goldblum’s scientist character lecturing the park’s proprietors on playing with the awesome power of nature.

CC passed away on March 4, 2020 at 18 years old — a full life by feline standards. The real consequences of her existence were less dramatic than predicted, but ultimately disappointing.

CC the Cat
CC with her surrogate mother, Annie. Credit: Texas A&M

Copy Cat’s birth didn’t herald an age of human cloning, but it did open the door to widespread animal cloning — including, as of last year, non-human primates — and eventually, to pet cloning.

A Mixed Legacy

Mark Westhusin, a scientist who was part of the team that successfully cloned CC, sees it as progress.

“CC’s passing makes me reflect on my own life as much as hers,” Westhusin said Wednesday. “Cloning now is becoming so common, but it was incredible when it was beginning. Our work with CC was an important seed to plant to keep the science and the ideas and imagination moving forward.”

CC lived as any typical house cat would, according to Shirley and Duane Kraemer, who adopted the famous feline. Duane Kraemer was also part of the research team involved in CC’s cloning.

cckraemer
Kraemer with CC. Credit: The Eagle (Bryan, Texas)

When Barbra Streisand admitted she had her dog cloned in 2017, she responded to the backlash by writing an editorial in the New York Times, defending cloning as a way to get over the heartbreak of losing a pet.

There are now several genetics companies that offer pet-cloning services for people who want to bring their dear dogs and cats back to life.

“The human–animal bond is a pretty strong thing,” said Kerry Ryan, a veterinarian who works for pet cloning firm Viagen. “Our pets truly are a part of the family, and people want to have a piece of their pets around forever.”

Clones, But Not Your Real Pets

Except, of course, they really aren’t bringing cats and dogs back to life, and the animals won’t be around forever. Viagen’s customers get a genetic copy, but that doesn’t mean the clone will look or even act the same.

“It can be a genetically identical animal that can come out looking differently than the animal that you had,” veterinarian Katy Nelson told WTOP in 2018.

To the people who can afford dropping between $25,000 and $50,000 to clone their cats and dogs, it doesn’t seem to matter that both nature and nurture will ensure differences.

Pet cloning has also drawn the ire of animal welfare activists and major organizations like the Humane Society and SPCA, who point out that every cloned cat or dog means one less home for strays in shelters.

The Humane Society “opposes cloning of any animals for commercial purposes due to major animal welfare concerns,” HSUS’s Vicki Katrinak told National Geographic. “Companies that offer to clone pets profit off of distraught pet lovers by falsely promising a replica of a beloved pet. With millions of deserving dogs and cats in need of a home, pet cloning is completely unnecessary.”

False Starts, Gene Splicing and Clone Experimentation

Then there’s the truly dark side of cloning.

Each cloning attempt involves implanting eggs into several surrogate cat (or dog) moms, and no one wants to know what happens to the other clones, whether or not they make it to term. There’s no law requiring the companies to disclose the fate of those animals, so for now it remains a mystery.

Not all clones end up in loving homes, either. The lucky handful do, but others are birthed into the world to be experimented on, like a quintet of monkeys cloned by scientists in China.

Cloned Monkeys from China
Scientists edited the DNA of these monkeys to remove a gene that regulates sleep, resulting in depression and anxiety, among other problems. Three of the five monkeys pictured here are sucking their thumbs, which is a sign of stress when primate infants are taken from their mothers. Credit: Institute of Neuroscience, Shanghai

The scientists who brought the monkeys to life also edited their genes, “cutting out a gene involved in regulating the sleep/wake cycle.” A 2019 story on Phys.org explained the consequences:

“The gene removal created multiple effects in edited monkeys, such as reduced sleep time, increased movement during the night, changed blood hormone levels, increased anxiety and depression, and some schizophrenia-like behaviors.”

Which was precisely the point: The research team wanted to study the unintended consequences of gene-editing on animals to learn more about how it could impact humans.

To be sure, none of this is Copy Cat’s fault.

The famous cat, who was delivered by a surrogate mother, lived for 18 years, a year or two more than the average house cat. She spent the remainder of her days as a typical house cat, albeit one whose vet visits and blood work were carefully pored over as geneticists confirmed she was as healthy as any other kitty.

But as science barrels forward and labs — many of them in countries with no regulations — are bringing cloned animals into this world, we should think about the consequences for animals and the human race.