Mitochondrial DNA in patients with essential tremor.

Essential tremor (ET) is one of the most common of the movement disorders. However, there has been little agreement in the neurological literature regarding diagnostic criteria for ET. It is not clear to what extent ET is associated with defects of mitochondrial DNA. In this study, we analyzed mitochondrial DNA (mtDNA) from the blood cells of the normal and ET patients using the long and accurate polymerase chain reaction (LA-PCR) and PCR. The large deletions were detected within several regions of mtDNA, but were not detected in the D-loop or CO I regions in ET patients. From our study, it is suggested that ET is a disorder showing a deficiency of mtDNA multicomplexes, and it also appears that mitochondrial dysfunction could be one of the causative factors of ET.