Ophthalmological Disorders in Dominant Spinal-cerebellar Ataxias

Inclusion Criteria: * Age between 18 and 80, * Presence of pathological expansion in ATXN1 (\> or equal to 39 CAG), ATXN2 (\> or equal to 33 CAG) or ATXN3 (\> or equal to 45 CAG) genes, responsible respectively for SCA1, SCA2 or SCA3 or a pathological expansion (\>250 GAA) in the FGF14 gene responsible for SCA27B pathology, * Sujet symptomatic (SARA greater than or equal to 4) or presymptomatic (SARA \< 4). Exclusion Criteria: * Study-specific criteria: * Subjects with systemic or ophthalmological disease that could affect the retina, impair fundus examination (severe cataract, severe/decompensated diabetes), or cause visual acuity below 20/40, intraocular pressure \> 20 mmHg, "cup to disc" ratio \> 0. 5, or severe refractive errors * Subjects with extremely severe neurological impairment, with a significant impact on the ability to perform most ophthalmological examinations; for example in patients for whom sitting, even with back support and cannot be maintained. The possibility of including subjects with a severe form will be evaluated on a case-by-case basis, according to the opinion of the principal investigator and the ophthalmologist. * General exclusion criteria relating to regulations: * Failure to obtain consent (adults, non-emancipated minors, persons not in a position to give consent, research carried out in emergency situations, etc.), * Participants who have reached the maximum amount of compensation for their participation inresearch, * Non-affiliation with a social security scheme, * Persons placed under court protection, * Person taking part in research.