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

Czech version

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

Overview

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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