Reviewing the Clinical Spectrum Related to Kmt2b Gene Mutations: Unusual Clinical Presentation and a Possible New Pathogenic Mutation

Introduction KMT2B related dystonia is a childhood onset generalized dystonia. Since its first description in 2016, different phenotypic spectrum have been reported. The aim of the case report is to provide data that may help to understand the spectrum of KMT2B-related disorders. We present two members of a family with a possible non-previously described pathogenic mutation and an unusual KMT2B related dystonia presentation: an adult onset and focal dystonia.Case Presentation The index patient is a 32 year-old woman with a generalized dystonia. Her maternal uncle presented a focal dystonia. Next-generation sequencing revealed a heterozygous missense mutation in KMT2B gene (19q13.12), described as a variant of uncertain significance (VUS). Although characteristic phenotype of KMT2B dystonia is a childhood onset generalized dystonia, different phenotypes have been related according to the kinds of mutations in this gene, also varying the age of symptom onset and the penetrance of the mutation. Asymptomatic or sub-clinical carriers and adult onset has been described. Due to the low prevalence of this variant in the general population and the low penetrance and high intrafamilial variability of this entity, we suggest that this mutation might be a pathogenic variant.ConclusionsKMT2B related dystonia is an emerging and prevalent monogenic dystonia whose incidence, genetic variability and clinical spectrum remain unknown. Despite the study of this gene is indicated in childhood onset dystonia, description of cases such as ours shows that its sequencing in patients with an adult-onset dystonia with family history can be useful for the diagnosis.

Occupational Injuries in Musicians: A Literature Review

ABSTRACT Introduction The U.S. Department of Defense employs more musicians than any other organization in the USA with over 6,000 musicians employed. Musculoskeletal pathologies, behavioral health disorders, hearing loss, and dystonias account for the majority of reasons a musician seek medical care. The aim of this study is to review recent medical literature documenting occupational hazards in musicians. Materials and Methods Authors performed a literature review of publications related to musician performance-related musculoskeletal disorders (PRMDs) and performance-related pain (PRP), behavioral health disorders, dystonias, and hearing loss, published from 2004 to 2019 PubMed. Results The search returned 174 possible articles which, after review and exclusion, yielded 88 articles. Conclusions Medical literature suggests several risk factors for multiple disease categories. Practice time and history of PRMD/PRP were both associated with development of PRMD/PRP and focal dystonia. A history of behavioral health disorder was associated with development of focal dystonia. Clinicians should counsel their musician patients on strategies to minimize risks, and additional research is needed to identify specific causes of illnesses in musician populations.

Modulation of sensorimotor cortical oscillations in athletes with yips

The yips, an involuntary movement impediment that affects performance in skilled athletes, is commonly described as a form of task-specific focal dystonia or as a disorder lying on a continuum with focal dystonia at one end (neurological) and chocking under pressure at the other (psychological). However, its etiology has been remained to be elucidated. In order to understand sensorimotor cortical activity associated with this movement disorder, we examined electroencephalographic oscillations over the bilateral sensorimotor areas during a precision force task in athletes with yips, and compared them with age-, sex-, and years of experience-matched controls. Alpha-band event-related desynchronization (ERD), that occurs during movement execution, was greater in athlete with yips as compared to controls when increasing force output to match a target but not when adjusting the force at around the target. Event-related synchronization that occurs after movement termination was also greater in athletes with yips. There was no significant difference in task performance between groups. The enhanced ERD is suggested to be attributed to dysfunction of inhibitory system or increased allocation of attention to the body part used during the task. Our findings indicate that sensorimotor cortical oscillatory response is increased during movement initiation in athletes with yips.