Miryam Carecchio1, Celeste Panteghini2, Chiara Reale2, Chiara Barzaghi2, Valentina Monti2, Luigi Romito3, Francesco Sasanelli4, Barbara Garavaglia5. 1. Molecular Neurogenetics Unit, IRCCS Neurological Institute C. Besta, Via L. Temolo 4, 20126 Milan, Italy; Department of Pediatric Neurology, IRCCS Neurological Institute C. Besta, Via Celoria 11, 20133 Milan, Italy. 2. Molecular Neurogenetics Unit, IRCCS Neurological Institute C. Besta, Via L. Temolo 4, 20126 Milan, Italy. 3. Department of Neurology, IRCCS Neurological Institute C. Besta, Via Celoria 11, 20133 Milan, Italy. 4. Department of Neurology, AO Ospedale di Circolo di Melegnano, Strada Pandina 1, 20070 Vizzolo Predabissi (MI), Italy. 5. Molecular Neurogenetics Unit, IRCCS Neurological Institute C. Besta, Via L. Temolo 4, 20126 Milan, Italy. Electronic address: garavaglia@istituto-besta.it.
Abstract
INTRODUCTION: Mutations in GNAL have been associated with adult-onset cranio-cervical dystonia, but a limited number of cases have been reported so far and the clinical spectrum associated with this gene still needs to be fully characterized. METHODS: We identified an Italian family with adult-onset, dominantly-inherited dystonia whose members presented with different combinations of dystonia affecting the cervical, oro-mandibular and laryngeal regions associated with prominent tremor in some cases. Pure asymmetric upper limb dystonic tremor was present in one of the members and jerky cervical dystonia was also observed. A dedicate dystonia gene panel (Illumina) was used to screen for dystonia-associated genes and Sanger sequencing was performed to confirm results obtained and to perform segregation analysis. RESULTS: A novel single-base mutation in GNAL exon 9 (c.628G>A; p.Asp210Asn) leading to an aminoacidic substitution was identified and confirmed by Sanger sequencing. In silico prediction programmes as well as segregation analysis confirmed its pathogenicity. Clinically, no generalization of dystonia was observed after onset and DBS lead to an excellent motor outcome in two cases. CONCLUSION: We report a novel GNAL mutation and expand the clinical spectrum associated with mutations in this gene to comprise pure asymmetric dystonic tremor and a jerky cervical phenotype partially mimicking DYT11 positive cases.
INTRODUCTION: Mutations in GNAL have been associated with adult-onset cranio-cervical dystonia, but a limited number of cases have been reported so far and the clinical spectrum associated with this gene still needs to be fully characterized. METHODS: We identified an Italian family with adult-onset, dominantly-inherited dystonia whose members presented with different combinations of dystonia affecting the cervical, oro-mandibular and laryngeal regions associated with prominent tremor in some cases. Pure asymmetric upper limb dystonic tremor was present in one of the members and jerky cervical dystonia was also observed. A dedicate dystonia gene panel (Illumina) was used to screen for dystonia-associated genes and Sanger sequencing was performed to confirm results obtained and to perform segregation analysis. RESULTS: A novel single-base mutation in GNAL exon 9 (c.628G>A; p.Asp210Asn) leading to an aminoacidic substitution was identified and confirmed by Sanger sequencing. In silico prediction programmes as well as segregation analysis confirmed its pathogenicity. Clinically, no generalization of dystonia was observed after onset and DBS lead to an excellent motor outcome in two cases. CONCLUSION: We report a novel GNAL mutation and expand the clinical spectrum associated with mutations in this gene to comprise pure asymmetric dystonic tremor and a jerky cervical phenotype partially mimicking DYT11 positive cases.
Authors: Hind Baba Aïssa; Romain W Sala; Elena Laura Georgescu Margarint; Clément Léna; Daniela Popa; Jimena Laura Frontera; Andrés Pablo Varani; Fabien Menardy; Assunta Pelosi; Denis Hervé Journal: Elife Date: 2022-06-14 Impact factor: 8.713