ATXN1 and cerebellar ataxia: Substitution of Ser776 with a non-phosphorylatable alanine (S776A) markedly attenuates the toxicity of the long-polyQ variant: mice carrying ATXN1[82Q]-S776A do not develop overt ataxia at the same repeat length, exhibit only mild Purkinje cell abnormalities, and show minimal motor impairment (no frank ataxic gait and only subtle deficits on the accelerating rotarod) [106].