Myoclonic Epilepsy and Deafness in Siblings with the 7512T>C Mutation in the Mitochondrial Encoded tRNASer(UCN) Gene – Case Reports

Authors: P. Ješina 1;  K. Vinšová 1;  O. Brantová 1;  M. Tesařová 1;  Z. Hájková 1;  H. Hansíková 1;  L. Wenchich 1;  T. Honzík 1;  M. Magner 1;  J. Zámečník 2;  P. Ryška 3;  J. Zeman 1
Authors‘ workplace: Klinika dětského a dorostového lékařství UK 1. LF a VFN v Praze 1;  Ústav patologie a molekulární medicíny UK 2. LF a FN v Motole, Praha 2;  Radiologická klinika LF UK a FN Hradec Králové 3
Published in: Cesk Slov Neurol N 2010; 73/106(1): 68-72
Category: Case Report


Mitochondrial diseases are a very heterogeneous group of disorders affecting the nervous system, heart and skeletal muscle. The mutations are situated in nuclear DNA with Mendelian heredity and in mitochondrial DNA with maternal-type heredity. We describe a natural clinical course, the results of biochemical and molecular genetic measurements from two siblings with mitochondrial disorders due to mutation 7512T>C in the gene for mitochondrial tRNA for serine. The mutation is associated with myoclonic epilepsy, deafness, ataxia, calcification in the basal ganglia and decreased cytochrome c oxidase activity. The data should prove helpful in the exact diagnosis of patients with this phenotype.

Key words:
mitochondrial disease – myoclonic epilepsy – deafness – calcification in basal ganglia – cytochrom c oxidase deficiency – transfer RNA


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Paediatric neurology Neurosurgery Neurology

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