Molecular testing confirmed two GAA variants, NM_000152.5: c.842G>C, p.(Arg281Pro) and NM_000152.5: c.2560C>T, p.(Arg854*) in trans, and homozygosity for the HBB variant causative of SCA, consistent with his diagnosis. This evidence concerns the gene HBB and autosomal dominant cerebellar ataxia.