ATXN3 and Spinocerebellar ataxia type 3: Spinocerebellar ataxia type 3 (SCA3), also known as Machado–Joseph disease, is a rare autosomal dominantly inherited neurodegenerative disease [1,2] caused by an abnormal polyglutamine expansion within the ataxin-3 (ATXN3) protein [3,4].