What are Hereditary Ataxias? Ataxia is a neurologic disorder in which there is loss of coordination of movement. It can result from dysfunction of the cerebellum and brain stem and their afferent or efferent pathways. The etiology of ataxia can be divided into 3 main categories: acquired, sporadic, and hereditary. Hereditary ataxias are one of the largest groups of hereditary progressive neurod...