• Mitochondrial disorders
• neurogenetics
• Parkinson's disease

The diagnosis of adult-onset spinocerebellar ataxia syndromes is often problematic since aetiologies of chronic progressive ataxic syndromes are wide-ranging, including hereditary, degenerative and various other acquired disorders. Most of these disorders have generally no characteristic clinical appearances, or neuroimaging, to help in making a specific diagnosis. Although these patients are carefully investigated by using several advanced laboratory tests, a large proportion of them remain unclassified. However, genetic factors appear to be an important cause. It is not only familial forms, in which specific mutations of spinocerebellar ataxia (SCA) subtypes often account for 40%–70%, but also common SCA mutations are identified in up to 22% of sporadic cases.1

In this regard, Pfeffer, et al demonstrated that mutations of the mitochondrial ATP synthase six gene (MTATP6) may be relatively common in previous unclassified adult-onset spinocerebellar ataxic syndromes.2 All patients were familial forms, but although there …