Spongiform LeucoEncephaloMyelopathy (SLEM), sometimes referred to as Shaking puppy syndrome, affects the puppies from the time they begin to support weight and attempt to walk. Border Terriers affected by SLEM show severe tremors predominately in the hind limbs, this creates a side to side shaking. Collaborating scientists at the University of Missouri, the Animal Health Trust and at Wisdom Health, have identified a mutation responsible for this disease in the Border Terrier.