Moebius syndrome

Moebius syndrome is a rare congenital neurological disorder caused by underdevelopment of the sixth and seventh cranial nerves, which control eye movement and facial expression. Most people born with the condition cannot move their eyes from side to side, cannot close their eyelids fully, and have a fixed, expressionless face because the muscles that would normally smile, frown, or blink do not receive proper nerve signals. Intelligence is unaffected, though speech and feeding can be difficult in infancy because the same nerves also govern swallowing and lip movement. The German neurologist Paul Julius Möbius gave the first clinical description of the syndrome in 1888. Its exact cause is still not fully understood, but the leading explanation is a temporary interruption of blood flow to the brainstem during early pregnancy. Recognized contributing factors include exposure to the drug misoprostol, which raises the risk roughly thirtyfold, as well as thalidomide and cocaine exposure and certain chromosomal abnormalities. Advocacy and support work expanded after the Moebius Syndrome Foundation held its first conference in Los Angeles in 1994.