A curly is a hypoallergenic horse.

The KRT25 and SP6 genes are responsible for the curly coat in horses.

Also the Smooth Coat Miniatures are also hypoallergenic for many. A Smooth Coat is a Curly Mini that did not inherit the curly coat gene, so is without the Curled Coat. Many of these Smooth Coats have what we call a "bunny fur coat", with a few swirls and fluffy hair.