Apart from a few studies including oculographic recordings of a single ataxia5,10,15,16, specific oculomotor abnormalities of AOA1, AOA2 and AT have never been systematically compared and whether they may be distinguished through oculomotor findings is presently unknown just as whether video-oculography (VO) and biomarkers such as AFP and albumin serum level can assist diagnosis of AOA1, AOA2 and AT in clinical practice. This evidence concerns the gene AFP and ataxia telangiectasia.