OCULAR APRAXIA, defined as the limitation of ocular movements on command dissociated from movements of pursuit, is a major clinical feature in 2 well-defined hereditary ataxias, spinocerebellar ataxia type 2 and ataxia-telangiectasia (A-T). In 1941, Louis-Barr1 described A-T as an autosomal recessive cerebellar ataxia beginning in early childhood, associated with ocular apraxia, choreoathetosis, oculocutaneous telangiectasia, immune dysfunction, chromosomal instability, and hypersensitivity to x-rays, with a high incidence of respiratory infections and neoplasias; it was associated with chromosomal instability and DNA repair defects2 and mapped to chromosome 11.3 Spinocerebellar ataxia type 2 is an adult-onset, autosomal dominant, cerebellar ataxia, first reported in India by Wadia and Swami,4 that has a large cluster in the Cuban province of Holguin.5 The mutation, a CAG repeat expansion in the short arm of chromosome 12, was identified in 1996.6