friedreichs ataxia (frda) is an autosomal recessive neurodegenerative disorder caused by decreased expression of the protein frataxin. frataxin deficiency leads to excessive free radical production and dysfunction of chain complexes. mitochondrial dna (mtdna) could be considered a candidate modifier factor for frda disease, since mitochondrial oxidative stress is thought to be involved in the p...

It is generally accepted that mitochondria are able to proliferate even in postmitotic cells due to their natural turnover and also to satisfy increased cell energy requirements. However, no detailed studies are available, particularly with respect to specific cell types. Since [3H]-thymidine is incorporated not only into nuclear (n) DNA but also into the DNA of cytoplasmic mitochondria, an aut...

PURPOSE In the central nervous system (CNS), increased mitochondrial DNA (mtDNA) damage is associated with aging and may underlie, contribute to, or increase the susceptibility to neurodegenerative diseases. Because of the focus on the retinal pigment epithelium (RPE) and choroid as tissue relevant to age-related macular degeneration (AMD), we examined young and aged RPE and choroid, harvested ...

Delimiting the boundaries of species involved in radiations is critical to understanding the tempo and mode of lineage formation. Single locus gene trees may or may not reflect the underlying pattern of population divergence and lineage formation, yet they constitute the vast majority of the empirical data in species radiations. In this study we make use of an expressed sequence tag (EST) datab...

The effect of caloric restriction (CR) (40%) on the rates of mitochondrial H2O2 production and oxygen consumption and oxidative damage to nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) was studied for short-term (6-wk) and long-term (1-year) periods in the heart of young and old rats. Short-term CR did not change any of the parameters measured. However, long-term CR significantly decreased th...

BACKGROUND Diabetes mellitus (DM) is increasing in men of reproductive age. Despite this, the prevalence of diabetes in men attending fertility clinics is largely unknown. Furthermore, studies examining the effects of DM on sperm fertility potential have been limited to conventional semen analysis. METHODS Conventional semen analysis (semen volume, sperm count, motility and morphology) was pe...

objective(s): as mitochondrial oxidative stress is probably entailed in atp production, a candidate modifier factor for the long qt syndrome (lqts) could be mitochondrial dna (mtdna). it has been notified that ion channels' activities in cardiomyocytes are sensitive to the atp level. materials and methods: the sample of the research was an iranian family with lqts for mutations by pcr-sscp...

The D-loop region is a hot spot for mitochondrial DNA (mtDNA) alterations, containing two hypervariable segments, HVS-I and HVS-II. In order to identify polymorphic sites and potential genetic background accounting for Hypertrophic CardioMyopathy (HCM) disease, the complete non-coding region of mtDNA from 31 unrelated HCM patients and 45 normal controls were sequenced. The sequences were aligne...

Offspring produced by nuclear transfer (NT) have identical nuclear DNA (nDNA). However, mitochondrial DNA (mtDNA) inheritance could vary considerably. In sheep, homoplasmy is maintained since mtDNA is transmitted from the oocyte (recipient) only. In contrast, cattle are heteroplasmic, harboring a predominance of recipient mtDNA along with varying levels of donor mtDNA. We show that the two nonh...