EP202: A new pathologic KMT2B variant associated with childhood onset dystonia presenting as variable phenotypes among family members

Abstract

KMT2B-related dystonia (DYT-KMT2B) is an autosomal dominant disease resulting in a complex movement disorder. KMT2B is expressed ubiquitously throughout human tissues, with the greatest expression within the cerebellum. Additionally, KMT2B-dystonia patients have reduced KMT2B expression. To date, less than eighty affected individuals of varying genotypes have been identified. DYT-KMT2B typically presents in early childhood with lower extremity dystonia in the first decade. DYT-KMT2B is known to progress into generalized dystonia with associated dysphagia, spasticity, dysarthria, and dysphonia, generally two to eleven years after symptom onset.