Schematic representation of the ATXN3 gene structure. Exons are numbered from 1 to 11 and are presented as boxes. Filled blue boxes indicate the coding regions, hatched horizontal boxes represent the 5'-untranslated region (UTR), and hatched diagonal boxes correspond to the 3'-UTR. The location of the polymorphic (CAG)n tract is indicated. Polyadenylation consensus sequences are marked from A1 to A8.