Musladin-Lueke syndrome (MLS) is an inherited disorder affecting dogs. Dogs with this disorder have increased amounts of Connective Tissue in the skin and joints. Clinical signs are usually noted at birth and include stiff, sometimes contracted joints that cause dogs to walk upright and often on their tip-toes, giving them a “ballerina walk”. Affected dogs are smaller than littermates with creased ears and thick, tight skin. Other features of this disorder include short outer toes, broad flat foreheads with wide-set slanted eyes and high-set ears. Dogs may also exhibit a failure to thrive, have seizures or experience “phantom pains”. Symptoms continue to progress until dogs are about 1 year of age at which time they appear to stabilize. Dogs with this disorder typically have a normal life span, but commonly develop arthritis.