Studies in model mice have underscored the importance of ataxin-7 in neural function, as expression of polyQ-expanded ataxin-7 yields phenotypes representative of SCA7 neurodegeneration, including cone-rod dystrophy retinal degeneration, cerebellar degeneration, brainstem pathology, and cortical dysfunction (La Spada et al., 2001; Yoo et al., 2003; Yvert et al., 2001). This evidence concerns the gene ATXN7 and Cone rod dystrophy.