Cornish have rows of hair. And their personalities are different too. Cornish are busy all the freaking time, like elves, always having to do something. The theory is that people with allergies can tolerate rexes. All cats have little proteins in their oils that makes allergic folks go nuts.
Nothing is non-allergenic.
Even those nasty, plastic bed-mite covers one can put on your mattress. They smell like beach balls, and people can be allergic to that too. You know, that plastic smell. I had a cover on my bed when I was little. Not so much for allergies as for the uncontrollable bladder.