In many patients with cerebellar ataxia, the etiology is unknown. Sensitivity to gluten (wheat protein) has been suggested as a cause for cerebellar ataxia even in the absence of malabsorption symptoms or intestinal pathology. However, the prevalence of gluten sensitivity in patients presenting with cerebellar ataxia is unknown and the effect of gluten-free diet on gluten sensitivity-associated cerebellar ataxia has not been systematically studied. The aim of this project is: 1) To identify gluten sensitive cerebellar ataxia patients attending the Human Motor Control Clinic at the NIH using tests for celiac disease antibodies as a screening method. 2) To conduct open-label controlled clinical trial to assess the efficacy of gluten-free diet in the patients identified using a detailed cerebellar ataxia scale as an objective clinical measure.