A KMT2B Frameshift Variant Causing Focal Dystonia Restricted to the Oromandibular Region After Long-Term Follow-up

Author: Alfand Marl F. Dy CLOSAS ¹ ; Katja LOHMANN ; Ai Huey TAN ; Norlinah Mohamed IBRAHIM ; Jia Lun LIM ; Yi Wen TAY ; Kalai Arasu MUTHUSAMY ; Azlina Binti AHMAD-ANNUAR ; Christine KLEIN ; Shen-Yang LIM
Author Information

1. Division of Neurology, Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
Publication Type:3
From:Journal of Movement Disorders 2023;16(1):91-94
CountryRepublic of Korea
Language:English
Abstract: KMT2B-linked dystonia (DYT-KMT2B) is a childhood-onset dystonia syndrome typically beginning in the lower limbs and progressing caudocranially to affect the upper limbs with eventual prominent craniocervical involvement. Despite its recent recognition, it now appears to be one of the more common monogenic causes of dystonia syndromes. Here, we present an atypical case of DYT-KMT2B with oromandibular dystonia as the presenting feature, which remained restricted to this region three decades after symptom onset. This appears to be the first reported case of DYT-KMT2B from Southeast Asia and provides further supporting evidence for the pathogenic impact of the KMT2B c.6210_6213delTGAG variant.