Joubert syndrome is an inherited disorder that affects the area of the brain that controls balance and coordination; it is characterized by symptoms such as loss of muscle tone, developmental delay, and mental retardation.

An international study by researchers at Seattle Children's Hospital Research Institute, the University of Washington School of Medicine, and Radboud University in Nijmegen, Netherlands has identified a new genetic cause for Joubert syndrome (JS). Joubert syndrome is an inherited condition that affects development of the cerebellum and brainstem, the structures in the brain that coordinate movements and regulate basic functions such as breathing, swallowing, heart rate and consciousness.