Spasticity and CA were a common combination in 10 patients with variants in FBXO7, PLEKHG2, TPP1, ITPR1, KIF1A, and SPG7 genes; ataxia was also present in those with ITPR1, KIF1A, and SPG7 mutations; two probands with mutations in EXOSC3 suffered from early severe encephalopathy and CA, with progressive motor neuron signs after the first years of life. This evidence concerns the gene EXOSC3 and Ataxia.