A rare, autosomal recessive inherited disorder caused by mutation in the TYMP gene. It affects several parts of the body, particularly the gastrointestinal tract and nervous system. Signs and symptoms can appear in infancy, but they often begin by age twenty. The gastrointestinal signs and symptoms result from gastrointestinal dysmotility and include fullness after eating small amounts of food, dysphagia, nausea and vomiting after eating, abdominal pain, diarrhea, and intestinal blockage. The nervous system abnormalities include leukoencephalopathy, tingling, numbness, peripheral neuropathy, ptosis, ophthalmoplegia, and hearing loss. [ ]