FGF14 and peripheral neuropathy: In a study of 45 patients with a combination of cerebellar ataxia and either peripheral neuropathy or bilateral vestibular failure or both (and negative for the RFC1 repeat expansion), screening for the FGF14 GAA repeat expansion was positive in 43% of patients with ataxia and vestibular failure, 38% with ataxia and neuropathy and 27% with ataxia, neuropathy and vestibular areflexia [19▪].