Disease-causing mutations in mitochondrial DNA (mtDNA) are typically heteroplasmic and therefore interpretation of genetic tests for mitochondrial disorders can be problematic. Detection of low level heteroplasmy is technically demanding and it is often difficult to discriminate between the absence of a mutation or the failure of a technique to detect the mutation in a particular tissue. The re...

Human mitochondrial tRNA (hmt-tRNA) mutations are associated with a variety of diseases including mitochondrial myopathies, diabetes, encephalopathies, and deafness. Because the current understanding of the precise molecular mechanisms of these mutations is limited, there is no efficient method to treat their associated mitochondrial diseases. Here, we use a variety of known mutations in hmt-tR...

OBJECTIVES Information about epilepsy in mitochondrial disorders is scarce although a number or syndromic and non-syndromic mitochondrial disorders frequently manifest with focal or generalized seizures. Aim of the review was to describe epilepsy in syndromic and non-syndromic mitochondrial disorders with epilepsy as a dominant or collateral feature of the phenotype. METHODS Literature search...

5-Taurinomethyluridine (τmU) and 5-taurinomethyl-2-thiouridine (τmsU) are located at the wobble position of human mitochondrial (hmt) tRNA and tRNA, respectively. Both hypermodified units restrict decoding of the third codon letter to A and G. Pathogenic mutations in the genes encoding hmt-tRNA and hmt-tRNA are responsible for the loss of the discussed modifications and, as a consequence, for t...

The peptide nucleic acid (PNA)-directed PCR clamping technique was modified and applied to the detection of mitochondrial DNA mutations with low heteroplasmy. This method is extremely specific, eliminating false positives in the absence of mutant molecules, and highly sensitive, being capable of detecting mutations at the level of 0.1% of total molecules. Moreover, the reaction can be multiplex...

Post-transcriptional modifications are characteristic features of tRNAs and have been shown in a number of cases to influence both their structural and functional properties, including structure stabilization, amino-acylation and codon recognition. We have developed an approach which allows the investigation of the post-transcriptional modification patterns of human mitochondrial wild-type and ...

The term "mitochondrial diseases" (MD) refers to a group of disorders related to respiratory chain dysfunction. Clinical features are usually extremely heterogeneous because MD may involve several tissues with different degrees of severity. Muscle and brain are mostly affected, probably because of their high dependence on oxidative metabolism. Muscle can be the only affected tissue or involved ...

BACKGROUND Mitochondrial DNA (mtDNA) genome mutations can lead to energy and respiratory-related disorders like myoclonic epilepsy with ragged red fiber disease (MERRF), mitochondrial myopathy, encephalopathy, lactic acidosis and stroke (MELAS) syndrome, and Leber's hereditary optic neuropathy (LHON). It is not well understood what effect the distribution of mutated mtDNA throughout the mitocho...

We report on an experimental study of the polarization properties of large mode-area photonic crystal fibers (PCFs). We find that such fibers may exhibit very low birefringence and polarization-mode dispersion (PMD) indicating a highly symmetrical hole structure over a long length. Moreover, the influence of temperature on the polarization-mode dispersion is investigated. The results show that ...