Autosomal Recessive Spastic Ataxia of Charlevoix-Saguenay (ARSACS) is an inherited disorder that affects muscle movement. The first symptom of ARSACS is an unsteady gait that usually appears between the age of 12 months and 18 months, as toddlers are learning to walk. The signs and symptoms worsen over the years, with increased abnormal tensing of the muscles, difficulty coordinating movements, muscle wasting, involuntary eye movements, and speech difficulties. Other problems may include deformities of the fingers and feet, pain in the hands and feet, abnormal foot reflexes, loss of the sensation of touch, yellow streaks of fatty tissue in the light-sensitive tissue at the back of the eye, and possible heart defect. Muscles continue to deteriorate to the point that most affected individuals require a wheelchair by the time they are adults. Affected individuals have a mental capacity that is at the lower end of the expected range for their age and are able to perform daily tasks throughout their lifetime. There is no cure for ARSACS; however medical surveillance and care may help to improve some symptoms and overall condition of life. ARSACS is caused by pathogenic variants in the SACS gene.