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The point mutation of mitochondrial DNA characteristic for MERRF disease is found also in healthy people of different ages
Author(s) -
Münscher C.,
Rieger T.,
Müller-Höcker J.,
Kadenbach B.
Publication year - 1993
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(93)81484-h
Subject(s) - mitochondrial dna , point mutation , mutation , biology , genetics , mitochondrial disease , myoclonic epilepsy , microbiology and biotechnology , polymerase chain reaction , non mendelian inheritance , heteroplasmy , gene , epilepsy , neuroscience
The A‐to‐G transition mutation in the tRNA Lys gene of mitochondrial DNA (mtDNA), characteristic for the maternally inherited MERRF syndrome (myoclonic epilepsy with ragged red fibers), has been identified by point mutation‐specific polymerase chain reaction in extraocular muscle from 11 of 16 healthy people of different ages. No mutation was found in navel‐string samples from 5 newborns, in HeLa cells, and in 2 individuals younger than 20 years. On the other hand, the mutation is present in all 5 tested 74–89‐year‐old individuals and in 6 of 9 20–70‐year‐old individuals. The amount of mutated from total mtDNA was estimated by ‘mispairing PCR’ in extraocular muscle of 2 individuals of 74 and 89 years to 2.0 and 2.4%, respectively. In most tissue samples the MERRF mutation occurs together with the ‘common deletion’ of mtDNA, which was previously shown to accumulate in healthy individuals with increasing age. It is proposed that during aging, deletions and point mutations of mtDNA accumulate, which could impair mitochondrial energetics.