This latter aspect is also confirmed by the heterozygous mutations of NPC1 and NPC2 genes that could contribute to dementia plus, at least in a subset of Calabrian patients [14], and by the novel TBP mutations that we found associated with an atypical clinical picture of SCA17 in a large autosomal dominant Calabrian family [9]. This evidence concerns the gene NPC1 and spinocerebellar ataxia type 17.