A case of ataxia with isolated vitamin E deficiency, in conjunction with supportive genetic studies, is reported. This is a neurodegenerative condition that involves a mutation in the tocopherol (alpha) transfer protein gene (TTPA). Measurement of serum vitamin E concentration should be included as part of the investigations in children with progressive ataxia, even in the absence of fat malabsorption. Early treatment with vitamin E may protect such patients against further neurological damage.