Hypoallergenic cat? This may sound funny or silly for some.  However, this is a serious matter for others, those many people who suffer from allergy to cats.

Researchers have put their feet on the route to producing a hypoallergenic cat as appears from their article in The CRISPR journal, giving hope to the many cat-lovers who find trouble adopting a cat because of their hypersensitivity.

Researchers targeted the major cat allergen, a protein called Fel d 1 that is shed by all cats. Fel d 1 is a protein secreted by cat salivary, sebaceous, perianal, and lachrymal glands. Its precise biologic function is not yet known. The researchers tried to answer two questions: is it alright to inhibit the production of this protein in the cat? and is it possible?

Fel d 1 is formed of two types of chains. Researchers compared the protein genes CH1 and CH2 in the domestic cat and exotic cat species. The multisequence alignments suggested that the Fel d 1 gene sequences are not conserved, with relatively low sequence identities. This lack of evolutionary conservation implies that the Fel d 1 genes may be nonessential for cats and suggests that CH1 and CH2 are suitable targets for gene deletion.

Then the researchers performed CRISPR knockouts studies in cultured feline cells. The results indicated that Fel d 1 is amenable to gene editing using CRISPR and provide the first step in creating Fel d 1 knockout cats.

Future studies will aim to develop a means for deleting the Fel d 1 genes in adult cats and effectively rendering the cats hypoallergenic. This is expected to improve the health of cat allergic patients substantially by effectively removing the allergen at the source.

While these studies suggest that Fel d 1 may be nonessential, the definitive test of functionality must be experimental. Deleting Fel d 1 with gene editing technology remains the critical step for identifying the biologic function of the allergen and for determining whether that function is vital for the cats’ survival.

Reference: Nicole F. Brackett, Brian W. Davis, Mazhar Adli, Anna Pomés, and Martin D. Chapman. The CRISPR Journal. ahead of print http://doi.org/10.1089/crispr.2021.0101

Go to the News Board