Autosomal Recessive Spastic Ataxia of the Charlevoix-Saguenay (ARSACS) is a hereditary progressive neurological disorder that primarily affects people from the Saguenay–Lac-Saint-Jean and Charlevoix regions of Quebec or descendants of native settlers in this region. This disorder has also been demonstrated in people from various other countries including India.[5] It is characterized by degeneration of the spinal cord and progressive damage of the peripheral nerves. The disorder is caused by a gene mutation on chromosome 13 (SACS) of the 22 chromosomes that determine characteristics that are not related to sex. This is an autosomal recessive disorder, meaning that both parents must be carriers of the gene in order to have a 25% chance of their child having the disorder at each pregnancy.[6] Mutations of the gene is usually a deletion or replacement of a nucleotide in the SACS gene. The mutation of the SACS gene causes the production of an unstable, poorly functioning SACSIN protein. It is unclear as to how this mutation affects the central nervous system (CNS) and skeletal muscles presenting in the signs and symptoms of ARSACS.[7]

ARSACS is usually diagnosed in early childhood, approximately 12–24 months of age when a child begins to take their first steps. It is a lack of coordination and balance during gait that is first noticed. Children with the disorder take frequent falls and appear to have an unsteady (Ataxic) gait. Some of the signs and symptoms include:[8] Stiffness of the legs, appendicular and trunk ataxia, hollow foot and hand deformities, ataxic dysarthria, distal muscle wasting, horizontal gaze nystagmus, and spasticity.[

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