A MERRF/MELAS overlap syndrome associated with a new point mutation in the mitochondrial DNA tRNA(Lys) gene.
Eur J Hum Genet
; 1(1): 80-7, 1993.
Article
in En
| MEDLINE
| ID: mdl-8069654
ABSTRACT
Several members of a three-generation kindred from Sardinia were affected by a maternally inherited syndrome characterized by features of both myoclonus epilepsy with ragged-red fibers (MERRF) and mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS). Clinically, symptoms such as myoclonus epilepsy, neural deafness and ataxia were variably associated with stroke-like episodes and/or migrainous attacks. Morphologically, numerous MELAS-associated SDH-stained vessels were observed in muscle biopsies, either alone or in combination with ragged-red fibers, the morphological hallmark of MERRF. Sequence analysis of the mtDNA tRNA genes revealed the presence of a single, heteroplasmic T-->C transition at nt 8356, in the region of the tRNA(Lys) gene corresponding to the T-psi-C stem. The T-->C(8356) transition was exclusively found in the maternal lineage of our family, and the relative amount of the mutant mtDNA species in muscle was correlated with the severity of the clinical presentation. Therefore, we propose that the T-->C(8356) transition is responsible for the mitochondrial encephalomyopathy found in our family, and must be added to the expanding list of the pathogenetically relevant mutations of human mtDNA.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
DNA, Mitochondrial
/
RNA, Transfer, Lys
/
Point Mutation
/
Mitochondrial Myopathies
/
MERRF Syndrome
/
MELAS Syndrome
Type of study:
Risk_factors_studies
Limits:
Adolescent
/
Adult
/
Child
/
Female
/
Humans
/
Male
/
Middle aged
Country/Region as subject:
Europa
Language:
En
Journal:
Eur J Hum Genet
Journal subject:
GENETICA MEDICA
Year:
1993
Type:
Article
Affiliation country:
Italy