Cat allergies could soon be a thing of the past as Virginia company develops new gene-editing injection
Cat allergies are estimated to occur in about 10% of the population worldwide. Treatment options for sufferers include antihistamines, decongestants and nasal steroids. But now, a company based in Virginia, United States, could have figured out a way to make all cats allergen-free through gene-editing.
Ten cat allergens have been identified as causing reactions in humans. However, the main culprit is a protein called Fel d 1, which is produced by salivary, sebaceous (in the skin), perianal (in the anal sacs) and lacrimal (in the eye) glands.
Fel d 1 probably has a role in keeping cats' skin healthy and may also interact with their hormonal systems. Male cats make the most Fel d 1; neutered toms make slightly less, and female cats lesser than that.
Cats spread the Fel d 1 protein on to their hair and skin during grooming. When dry skin cells and hair are shed with invisible dander, Fel d 1 can float in the air for long periods and readily stick to surfaces such as sweaters, blankets and carpeting.
Indoor Biotechnologies (InBio), in Charlottesville, Virginia, conducted studies on how to use gene-editing to remove the two genes that code for Fel d 1 with the ultimate goal of having an allergen-free cat. In February, the company published a paper detailing the results of the study. The company successfully used the gene-editing tool, CRISPR, to delete those genes.
No animals were harmed during the studies, which were conducted on feline cells. To conduct the CRISPR experiments, Indoor Biotechnologies worked with a local arm of the Society for the Prevention of Cruelty to Animals to obtain tissue samples from 50 cats.
"We've been hypothesizing about what would happen if you could delete the gene from cats," Martin Chapman, CEO of Indoor Biotechnologies and a former professor of medicine and microbiology at the University of Virginia, told OneZero Magazine. "What we hope will ultimately come out of this is a cat that is genetically modified so that it doesn’t produce Fel d 1."
The company is not interested in breeding new, genetically modified cats. Instead, it aims to develop a CRISPR-based drug to edit the DNA of cats that people already have. If the drug proves to be safe, cat-owners can go down to their local vets for the injection and go back home with cats that now, won't cause allergies.
The current research is the first step in the company's plan for the same. Next, Indoor Biotechnologies is planning to edit out the gene in cat salivary tissues in the lab to observe whether it stops producing the allergy-causing protein.
Whether removing the genes responsible for Fel d 1 is harmful to cats is still unknown to scientists. One method to understand the consequences would be to delete the protein-producing gene in cat embryos and transfer the embryos to the womb of a female cat. The resulting kittens will then have to be studied for any medical problems. Suffice to say, the study involves many ethical conundrums and could invite the ire of animal rights groups.
There are other less invasive methods available. Nestlé's researchers at Purina PetCare have developed a cat food that uses the antigen-antibody interaction to deactivate some of the Fel d 1 by binding it to antibodies derived from chicken eggs. The approach does not stop the cat from producing Fel d 1. Instead, it transforms the Fel d 1 in saliva into a compound the human immune system doesn't react to.