Absence of Mutation Enrichment for Genes Phylogenetically Conserved in the Olivocerebellar Motor Circuitry in a Cohort of Canadian Essential Tremor Cases
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Essential Tremor is a prevalent neurological disorder of unknown etiology. Studies suggest that genetic factors contribute to this pathology. To date, no causative mutations in a gene have been reproducibly reported. All three structures of the olivocerebellar motor circuitry have been linked to Essential Tremor. We postulated that genes enriched for their expression in the olivocerebellar circuitry would be more susceptible to harbor mutations in Essential Tremor patients. A list of 11 candidate genes, enriched for their expression in the olivocerebellar circuitry, was assessed for their variation spectrum and frequency in a cohort of Canadian Essential Tremor cases. Our results from this list of 11 candidate genes do not support an association for Essential Tremor in our cohort of Canadian cases. The heterogenic nature of ET and modest size of the cohort used in this study are two confounding factors that could explain these results.
KeywordsEssential Tremor Movement disorder Genetics Inferior olive Cerebellum
G.A.R. is supported by the Canadian Institutes of Health Research Foundation Scheme grants (#332971) and holds a Canada Research Chair in Genetics of the Nervous System and the Wilder Penfield Chair in Neurosciences.
J.F.S. had a fellowship from the Canadian Institute of Health Research.
G.H. is the recipient from a Gerard Bouchard scholarship from the Réseau de Médecine Génétique Appliqué (RMGA).
C.S.L was the recipient of a Tim E. Noël fellowship from ALS Canada.
Compliance with Ethical Standards
Ethics approval for the recruitment and genetic analysis of ET-affected individuals and their families has been granted at the following institutes: MUHC (McGill University Health Centre) (Roubank protocol no.: 14051), CRCHUM (Centre de recherche du Centre hospitalier de l’Université de Montréal) (project no.: ND043076).
Conflict of Interest
The authors declare that they have no conflict of interest.
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