In conclusion, the present report describes a child with infantile SCA2 with a massive expansion of CAG trinucleotides of the ATXN2 gene reported up to date in the literature, which resulted in a very early onset of clinical findings, since birth, and whose phenotype mainly corresponds to the severe affection of the central and peripheral nervous system. This evidence concerns the gene ATXN2 and spinocerebellar ataxia type 2.