TG and Friedreich ataxia: To determine the etiology of ataxia, extensive workup was carried out including somatosensory evoked potential recording, blood and urine chemistry tests, assay of serum levels of vitamin B12 and thyroid hormones, venereal disease research laboratory (VDRL) test, anti-human immunodeficiency virus (HIV) antibody test and genetic studies for spinocerebellar ataxia (types 1, 2, 3, 6, 7 and 8), Friedreich ataxia and dentato-rubro-pallido-luysian atrophy.