Junctional epidermolysis bullosa (JEB) is an inherited disorder affecting foals of Belgium Draft Horses, American Saddlebreds and their relatives. The condition is caused by a mutation that inhibits the body's ability to produce certain proteins responsible for holding the skin onto the body. The foal starts to lose their hoof wall which often causes detachment of the hoof from its body. Oral ulcers may also appear. As the condition worsens, the foal will suffer increasing pain and discomfort and severe infections from the lesions.