Can you be allergic to only one cat?

It is possible to be allergic to only one cat. Cat allergies are caused by allergens found in the cat's dander, saliva, and urine. The amount of allergens produced by a cat can vary from cat to cat, and some people may be more allergic to certain cats than others. Additionally, some people may develop a sensitivity to only one of the three major allergens produced by cats, which could result in an allergy to only one specific cat.