Test Details: SCA6 is an autosomal dominant ataxia with vibratory & proprioceptive sensory loss. It manifests later in life and is associated with cerebellar degeneration. In SCA 6 there is a CAG trinucleotide repeat in chromosome 19p which results in abnormal CACNA1A protein. Missense mutations in the same gene cause Familial hemiplegic migraine while nonsense mutations result in Hereditary paroxysmal cerebellar ataxia or Episodic ataxia.