Congenital cerebellar ataxias are a heterogeneous group of non-progressive disorders characterized by hypotonia and developmental delay followed by the appearance of ataxia, and often associated with dysarthria, mental retardation, and atrophy of the cerebellum. We report the mapping of a disease gene in a large inbred Lebanese Druze family, with five cases of a new form of non-progressive autosomal recessive congenital ataxia associated with optic atrophy, severe mental retardation, and structural skin abnormalities, to a 3.6-cM interval on chromosome 15q24-15q26.