Background: Tremor is a symptom of many diseases and can constitute a disease of its own: essential tremor.
Objective: The genetics of essential tremor and differential diagnosis of monogenic diseases with the symptom tremor.
Material and methods: Literature search and search of clinical genetics databases, e.g. OMIM, GeneReviews, MDSGene and the German Neurological Society (DGN) guidelines.
Results: The genetics of essential tremor remain unresolved in spite of large, adequately powered studies. Tremor is a symptom of differential diagnostic value in many movement disorders. A slight tremor might have been missed or not reported in many descriptions of movement disorders.
Conclusion: Progress in the genetics of essential tremor probably requires a more detailed phenotyping allowing stratification into phenotypically defined subgroups. Tremor should always be included in the examination and description of movement disorders even if tremor is not a cardinal symptom. Tremor might be helpful in the differential diagnosis of hereditary dystonia, hereditary ataxia, spastic paraplegia and other movement disorders.
Keywords: Essential tremor; Hereditary ataxia; Hereditary dystonia; Monogenic tremor; Spastic spinal paralysis.