ATXN7 and spinocerebellar ataxia 7: Spinocerebellar ataxia 7 (SCA7) is an Autosomal Dominant Cerebellar Ataxia (ADCAs) caused by the expansion of the cytosine-adenine-guanine (CAG) trinucleotide in the codon region of the chromosome 3p21 encoding the protein ataxin 7 [1].