Maternally Inherited Deafness and Unusual Phenotypic Manifestations Associated with A3243G Mitochondrial DNA Mutation

Katalin KOMLÓSI1, Richárd KELLERMAYER1, Anita MAÁSZ1, Viktória HAVASI1, Katalin HOLLÓDY2, Olga VINCZE3, Hajnalka MERKLI4, Endre PÁL4, Béla MELEGH1

1Department of Medical Genetics and Child Development, University of Pécs, Pécs, Hungary
2Department of Neurology, Pediatric Clinic, University of Pécs, Pécs, Hungary
3Kerpel-Frónius Ödön Children’s Hospital, County Hospital of Baranya, Pécs, Hungary
4Department of Neurology, University of Pécs, Pécs, Hungary


The mitochondrial DNA A3243G transition is a fairly common mutation which often associates with a MELAS (mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes) phenotype, however, a broad variety in the associated clinical picture has also been described. The patient reported here developed a generalized seizure at age 12, which was followed by bilateral hearing loss and occasional fatigue. The maternal inheritance pattern of hearing loss pointed to a possible mitochondrial origin, which was confirmed by molecular analysis of the mitochondrial DNA, revealing a heteroplasmic A3243G transition. Interestingly, muscle biopsy showed ragged-red fibers in the proband, which is unusual in the deafness-associated forms of this mitochondrial disorder. In addition to hearing impairment in four generations of the family, fatal cerebral embolization in the mother and fatal heart attack in the maternal grandmother (both at age 33) also occurred. On the contrary, diabetes, which usually accompanies the hearing loss variant, was specifically absent in all generations. The unusual manifestations associated with this mutation somewhat differentiate this family from the already known variants. Pathology & Oncology Research, Vol 11, Nr 2, 82-86, 2005

Key words: mtDNA A3243G; tRNALeu(UUR); mitochondrial disease; MELAS; deafness

Received: Apr 5, 2005; accepted: May 15, 2005
Correspondence: Béla MELEGH, Department of Medical Genetics and Child Development, University of Pécs, Pécs H-7624, Hungary; Tel: +36-72-536-427, Fax: +36-72-536-427; E-mail:

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