ATXN1 and cerebellar disorder: Therefore, the ataxin-1 construct of Lys772 cannot be sumoylated because of Ser776Ala amino acid variation causing the reduction of phosphorylation at serine776 and further result in spinocerebellar ataxia autosomal recessive 1 (DOID:1441)48, which is a clinically and genetically heterogeneous group of cerebellar disorders.