We initially focused on the RBP Fused in sarcoma (FUS/TLS), found to be mutated in familial amyotrophic lateral sclerosis (ALS) [19], since it was shown to be a major component of nuclear aggregates in several polyQ disorders, such as HD, SCA1 and SCA3 [20, 21]. This evidence concerns the gene ATXN3 and amyotrophic lateral sclerosis.