No evidence of association between CAG expansions and essential tremor in a large cohort of Italian patients.

Essential tremor (ET) is one of the most common movement disorders. However the pathogenesis is as yet unknown, although a genetic cause has long been recognised. Clinical and molecular evidences suggested that the ET gene might contain a CAG expanded region. In a cohort of Italian ET patients Repeat Expansion Detection (RED) approach did not demonstrate large CAG expansions. We extended the study towards specific targets: the channel proteins hSKCa3 and CACNL1A4. Direct assessment of CAG stretches within these two genes did not demonstrate any CAG expansion in affected subjects. Also a case-control analysis failed to reveal any evidence of association, thus excluding these genes as a cause of ET.