If you’ve always dreamed of owning a cat but allergies have prevented you from taking the plunge, science may have a solution for you.
Roughly 15% of people have some kind of allergic reaction to cats, causing symptoms ranging from watery eyes to extreme itchiness and congestion. These reactions are caused mainly by a protein called Fel d1 that cats secrete through their skin, salivary, and perianal glands, which ends up on their fur and thus on their owner.
While some cat breeds produce less of this protein than others—and are often touted as “hypoallergenic breeds”—all cats produce this protein in some amount, and even hairless cats can cause allergic reactions in people.
This has prevented many would-be cat owners from getting a pet cat—until now.
Researchers using CRISPR technology are very close to creating a truly hypoallergenic cat, which will be a boon for cat lovers who suffer from allergies. A biotech company based in the US, InBio, has found a way to block the genes that cause allergic reactions in cat owners.
CRISPR technology can remove, replace, or add a specific part of DNA to a chromosome. In short, researchers are using this tech to remove the gene that causes allergic reactions in cats—Fel d1.
While the estimated timeline for the successful editing of this gene is still several years away, InBio has already made significant progress. Fel d1 is made up of two different subunits and two genes—CH1 and CH2—are responsible for encoding each subunit. The research team initially deleted either the CH1 or the CH2 gene from cultured cat cells using CRISPR genome editing. Next, the team will remove all copies of these two genes at the same time, to confirm whether this does indeed prevent cells from making the Fel d 1 protein. Once this is successful, only then will the team create a cat that lacks the genes.
However, as ExcitedCats.com veterinarian Dr. Paola Cuevas states, Fel d1 is not the only problem, an important consideration in this process. “To date, the World Health Organization has recognized eight potentially allergenic albumins and dandlers secreted by cats. While the rest are less common and therefore considered secondary allergens, any of these allergens can cause a reaction and some people are allergic to more than one of the cat’s allergens.”
CRISPR is not the only method being used to eliminate the Fel d1 protein in cats. A team at the University of California in Los Angeles has created a part cat, part human compound that helps to stop allergic reactions—a piece of Fel d1 attached to the human antibody IgG Fcg1. The allergen from the cat attaches itself to antibodies on the histamine-producing immune cells, and the human part stops it from even getting started.
The team named it GFD, or “gamma Feline domesticus” and found over 90% less histamine in the cultures containing GFD. This shows that GFD may have successfully stopped the reaction of the immune cells with the cat allergen and could potentially help people who suffer from other allergies too.
Other scientists are working on a potential solution by injecting the Fel d1 protein into people with allergies, which can help build up a tolerance to the protein over time. Unfortunately, the treatment is still very expensive, and may not be permanent or even 100% effective. Another team is in the process of creating a hypoallergenic cat by vaccinating them against their own Fel d1 to stop the protein before it even reaches humans.
Food is also being touted as a potential solution to allergies in cats. Nestlé Purina now produces an antibody-coated cat food that neutralizes the feline allergen. The food, Pro Plan LiveClear, is said to reduce the Fel d1 concentration in cat hair and dander by 41%. While this may not be sufficient to help very sensitive allergy sufferers, it could make a large difference for many cat lovers.
There are, of course, other ways allergy sufferers can enjoy owning a feline, and Dr. Paola Cuevas reminds would-be cat owners that “other important considerations are that there can be great variation in the allergen levels produced between individual cats of the same breed, as well as during the different life stages of the same cat.” While there are no truly hypoallergenic cats—yet—by choosing the right breeds and taking the correct precautions, it’s certainly possible for allergy sufferers to own a cat without any major side effects.
