It is not a secret that some people cannot have cats because of an allergy to them. What causes this allergy? Can anything be done so that allergic people could have cats in spite of the problem? It is thought that the cat fur is the allergen. Actually, it is not so. The allergy is caused by a protein (FEL D1) contained in the cat saliva. While grooming, a cat puts this protein upon the fur, and thus it may further be spread to...