Dander is usually the simplistic explanation of the cause of animal allergies. Dander may be part of the cause of reactions to cats, but the real culprit and cause of the major reactions is from the secretion of the sebaceous glands. All skin, human or animal, contains these glands which produce an oily lubricant that keep the skin supple and the hair shiny. It is from this secretion that Fel d1, the cat allergen, surfaces. Lots of hair, little hair or no hair.
All cats produce oils from the sebaceous glands which cause problems.
The amount of hair that a cat has or does not have plays no significant part in its allergenicity. Cats, by the way, are probably responsible for two-thirds of all pet related allergies. Because dogs are not self-cleaners to the extent that cats are, dogs tend to have more dander, however, it is still the production of the sebaceous glands that greatly adds to the causal effect of allergic reactions to dogs. Like cats, the amount of hair a dog has or does not have, or whether the hair sheds or does not shed, plays no particular part in its ability to cause allergic reactions. Another common misconception is that the fur of some breeds is like human hair, and thus these breeds do not cause reactions.