Global epidemiological data show that SCA2 has a wide geographical distribution across the world, being the second most common subtype of autosomal dominant cerebellar ataxia at worldwide, after only to SCA3 (Machado–Joseph disease); nevertheless in some parts of the world, it represents the most common subtype and, in other regions, it is a less frequent disorder as compared to other SCAs (1). The gene discussed is ATXN2; the disease is autosomal dominant cerebellar ataxia.