Hereditary equine regional dermal asthenia

Hereditary equine regional dermal asthenia (HERDA) aka hyperelastosis cutis (HC), is an inherited autosomal recessive connective tissue disorder. It develops from a homozygous recessive mutation that weakens collagen fibers that allow the skin of the animal to stay connected to the rest of the animal. Affected horses have extremely fragile skin that tears easily and exhibits impaired healing. In horses with HC, the skin separates between the deep and superficial dermis. There is no cure. Most affected individuals receive an injury they cannot heal, and are euthanized. Managed breeding strategy is currently the only option for reducing the incidence of the disease.