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Sample records for ancient mitochondrial dna

  1. Ancient DNA

    DEFF Research Database (Denmark)

    Willerslev, Eske; Cooper, Alan

    2004-01-01

    ancient DNA, palaeontology, palaeoecology, archaeology, population genetics, DNA damage and repair......ancient DNA, palaeontology, palaeoecology, archaeology, population genetics, DNA damage and repair...

  2. Founding Amerindian mitochondrial DNA lineages in ancient Maya from Xcaret, Quintana Roo.

    Science.gov (United States)

    González-Oliver, A; Márquez-Morfín, L; Jiménez, J C; Torre-Blanco, A

    2001-11-01

    Ancient DNA from the bone remains of 25 out of 28 pre-Columbian individuals from the Late Classic-Postclassic Maya site of Xcaret, Quintana Roo, was recovered, and mitochondrial DNA (mtDNA) was amplified by using the polymerase chain reaction. The presence of the four founding Amerindian mtDNA lineages was investigated by restriction analysis and by direct sequencing in selected individuals. The mtDNA lineages A, B, and C were found in this population. Eighty-four percent of the individuals were lineage A, whereas lineages B and C were present at low frequencies, 4% and 8%, respectively. Lineage D was absent from our sample. One individual did not possess any of the four lineages. Six skeletons out of 7 dated from the Late Classic period were haplotype A, whereas 11 skeletons out of 16 dated from the Postclassic period were also haplotype A. The distribution of mtDNA lineages in the Xcaret population contrasts sharply with that found in ancient Maya from Copán, which lack lineages A and B. On the other hand, our results resemble more closely the frequencies of mtDNA lineages found in contemporary Maya from the Yucatán Peninsula and in other Native American contemporary populations of Mesoamerican origin. Copyright 2001 Wiley-Liss, Inc.

  3. Increased mitochondrial DNA diversity in ancient Columbia River basin Chinook salmon Oncorhynchus tshawytscha.

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    Bobbi M Johnson

    Full Text Available The Columbia River and its tributaries provide essential spawning and rearing habitat for many salmonid species, including Chinook salmon (Oncorhynchus tshawytscha. Chinook salmon were historically abundant throughout the basin and Native Americans in the region relied heavily on these fish for thousands of years. Following the arrival of Europeans in the 1800s, salmon in the basin experienced broad declines linked to overfishing, water diversion projects, habitat destruction, connectivity reduction, introgression with hatchery-origin fish, and hydropower development. Despite historical abundance, many native salmonids are now at risk of extinction. Research and management related to Chinook salmon is usually explored under what are termed "the four H's": habitat, harvest, hatcheries, and hydropower; here we explore a fifth H, history. Patterns of prehistoric and contemporary mitochondrial DNA variation from Chinook salmon were analyzed to characterize and compare population genetic diversity prior to recent alterations and, thus, elucidate a deeper history for this species. A total of 346 ancient and 366 contemporary samples were processed during this study. Species was determined for 130 of the ancient samples and control region haplotypes of 84 of these were sequenced. Diversity estimates from these 84 ancient Chinook salmon were compared to 379 contemporary samples. Our analysis provides the first direct measure of reduced genetic diversity for Chinook salmon from the ancient to the contemporary period, as measured both in direct loss of mitochondrial haplotypes and reductions in haplotype and nucleotide diversity. However, these losses do not appear equal across the basin, with higher losses of diversity in the mid-Columbia than in the Snake subbasin. The results are unexpected, as the two groups were predicted to share a common history as parts of the larger Columbia River Basin, and instead indicate that Chinook salmon in these subbasins

  4. Prehistoric introduction of domestic pigs onto the Okinawa Islands: ancient mitochondrial DNA evidence.

    Science.gov (United States)

    Watanobe, Takuma; Ishiguro, Naotaka; Nakano, Masuo; Takamiya, Hiroto; Matsui, Akira; Hongo, Hitomi

    2002-08-01

    Ancient DNAs of Sus scrofa specimens excavated from archaeological sites on the Okinawa islands were examined to clarify the genetic relationships among prehistoric Sus scrofa, modern wild boars and domestic pigs inhabiting the Ryukyu archipelago, the Japanese islands, and the Asian continent. We extracted remain DNA from 161 bone specimens excavated from 12 archaeological sites on the Okinawa islands and successfully amplified mitochondrial DNA control region fragments from 33 of 161 specimens. Pairwise difference between prehistoric and modern S. scrofa nucleotide sequences showed that haplotypes of the East Asian domestic pig lineage were found from archaeological specimens together with Ryukyu wild boars native to the Ryukyu archipelago. Phylogenetic analysis of 14 ancient sequences (11 haplotypes; 574 bp) indicated that S. scrofa specimens from two Yayoi-Heian sites (Kitahara and Ara shellmiddens) and two Recent Times sites (Wakuta Kiln and Kiyuna sites) are grouped with modern East Asian domestic pigs. Sus scrofa specimens from Shimizu shellmidden (Yayoi-Heian Period) were very closely related to modern Sus scrofa riukiuanus but had a unique nucleotide insertion, indicating that the population is genetically distinct from the lineage of modern Ryukyu wild boars. This genetic evidence suggests that domestic pigs from the Asian continent were introduced to the Okinawa islands in the early Yayoi-Heian period (1700-2000 BP), or earlier.

  5. Nuclear counterparts of the cytoplasmic mitochondrial 12S rRNA gene: a problem of ancient DNA and molecular phylogenies.

    Science.gov (United States)

    van der Kuyl, A C; Kuiken, C L; Dekker, J T; Perizonius, W R; Goudsmit, J

    1995-06-01

    Monkey mummy bones and teeth originating from the North Saqqara Baboon Galleries (Egypt), soft tissue from a mummified baboon in a museum collection, and nineteenth/twentieth-century skin fragments from mangabeys were used for DNA extraction and PCR amplification of part of the mitochondrial 12S rRNA gene. Sequences aligning with the 12S rRNA gene were recovered but were only distantly related to contemporary monkey mitochondrial 12S rRNA sequences. However, many of these sequences were identical or closely related to human nuclear DNA sequences resembling mitochondrial 12S rRNA (isolated from a cell line depleted in mitochondria) and therefore have to be considered contamination. Subsequently in a separate study we were able to recover genuine mitochondrial 12S rRNA sequences from many extant species of nonhuman Old World primates and sequences closely resembling the human nuclear integrations. Analysis of all sequences by the neighbor-joining (NJ) method indicated that mitochondrial DNA sequences and their nuclear counterparts can be divided into two distinct clusters. One cluster contained all temporary cytoplasmic mitochondrial DNA sequences and approximately half of the monkey nuclear mitochondriallike sequences. A second cluster contained most human nuclear sequences and the other half of monkey nuclear sequences with a separate branch leading to human and gorilla mitochondrial and nuclear sequences. Sequences recovered from ancient materials were equally divided between the two clusters. These results constitute a warning for when working with ancient DNA or performing phylogenetic analysis using mitochondrial DNA as a target sequence: Nuclear counterparts of mitochondrial genes may lead to faulty interpretation of results.

  6. Mitochondrial DNA variation, but not nuclear DNA, sharply divides morphologically identical chameleons along an ancient geographic barrier.

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    Dan Bar Yaacov

    Full Text Available The Levant is an important migration bridge, harboring border-zones between Afrotropical and palearctic species. Accordingly, Chameleo chameleon, a common species throughout the Mediterranean basin, is morphologically divided in the southern Levant (Israel into two subspecies, Chamaeleo chamaeleon recticrista (CCR and C. c. musae (CCM. CCR mostly inhabits the Mediterranean climate (northern Israel, while CCM inhabits the sands of the north-western Negev Desert (southern Israel. AFLP analysis of 94 geographically well dispersed specimens indicated moderate genetic differentiation (PhiPT = 0.097, consistent with the classical division into the two subspecies, CCR and CCM. In contrast, sequence analysis of a 637 bp coding mitochondrial DNA (mtDNA fragment revealed two distinct phylogenetic clusters which were not consistent with the morphological division: one mtDNA cluster consisted of CCR specimens collected in regions northern of the Jezreel Valley and another mtDNA cluster harboring specimens pertaining to both the CCR and CCM subspecies but collected southern of the Jezreel Valley. AMOVA indicated clear mtDNA differentiation between specimens collected northern and southern to the Jezreel Valley (PhiPT = 0.79, which was further supported by a very low coalescent-based estimate of effective migration rates. Whole chameleon mtDNA sequencing (∼17,400 bp generated from 11 well dispersed geographic locations revealed 325 mutations sharply differentiating the two mtDNA clusters, suggesting a long allopatric history further supported by BEAST. This separation correlated temporally with the existence of an at least 1 million year old marine barrier at the Jezreel Valley exactly where the mtDNA clusters meet. We discuss possible involvement of gender-dependent life history differences in maintaining such mtDNA genetic differentiation and suggest that it reflects (ancient local adaptation to mitochondrial-related traits.

  7. Ancient mitochondrial DNA and the genetic history of Eurasian beaver (Castor fiber) in Europe.

    Science.gov (United States)

    Horn, Susanne; Prost, Stefan; Stiller, Mathias; Makowiecki, Daniel; Kuznetsova, Tatiana; Benecke, Norbert; Pucher, Erich; Hufthammer, Anne K; Schouwenburg, Charles; Shapiro, Beth; Hofreiter, Michael

    2014-04-01

    After centuries of human hunting, the Eurasian beaver Castor fiber had disappeared from most of its original range by the end of the 19th century. The surviving relict populations are characterized by both low genetic diversity and strong phylogeographical structure. However, it remains unclear whether these attributes are the result of a human-induced, late Holocene bottleneck or already existed prior to this reduction in range. To investigate genetic diversity in Eurasian beaver populations during the Holocene, we obtained mitochondrial control region DNA sequences from 48 ancient beaver samples and added 152 modern sequences from GenBank. Phylogeographical analyses of the data indicate a differentiation of European beaver populations into three mitochondrial clades. The two main clades occur in western and eastern Europe, respectively, with an early Holocene contact zone in eastern Europe near a present-day contact zone. A divergent and previously unknown clade of beavers from the Danube Basin survived until at least 6000 years ago, but went extinct during the transition to modern times. Finally, we identify a recent decline in effective population size of Eurasian beavers, with a stronger bottleneck signal in the western than in the eastern clade. Our results suggest that the low genetic diversity and the strong phylogeographical structure in recent beavers are artefacts of human hunting-associated population reductions. While beaver populations have been growing rapidly since the late 19th century, genetic diversity within modern beaver populations remains considerably reduced compared to what was present prior to the period of human hunting and habitat reduction.

  8. Heteroplasmy and ancient translocation of mitochondrial DNA to the nucleus in the Chinese Horseshoe Bat (Rhinolophus sinicus complex.

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    Xiuguang Mao

    Full Text Available The utility and reliability of mitochondrial DNA sequences in phylogenetic and phylogeographic studies may be compromised by widespread and undetected nuclear mitochondrial copies (numts as well as heteroplasmy within individuals. Both numts and heteroplasmy are likely to be common across diverse taxa yet few studies have characterised their frequencies and variation at the intra-specific level. Here we report the presence of both numts and heteroplasmy in the mitochondrial control region of the Chinese horseshoe bat Rhinolophus sinicus. In total we generated 123 sequences from 18 bats, which contained two different numt clades (i.e. Numt-1 and Numt-2 and one mtDNA clade. The sequence divergence between Numt-1 and Numt-2 was 16.8% and each numt type was found in all four R. sinicus taxa, suggesting either two ancient translocations of mitochondrial DNA into the nucleus from the same source taxon, or a single translocation from different source taxa that occurred before the split of R. sinicus into different lineages. Within the mtDNA clade, phylogenetic relationships among the four taxa of R. sinicus were similar to those seen in previous results. Based on PCR comparisons, heteroplasmy was inferred between almost all individuals of R. sinicus with respect to sequence variation. Consistent with introgression of mtDNA between Central sinicus and septentrionalis, individuals from these two taxa exhibited similar signatures of repeated sequences in the control region. Our study highlights the importance of testing for the presence of numts and heteroplasmy when applying mtDNA markers to phylogenetic studies.

  9. Investigating the global dispersal of chickens in prehistory using ancient mitochondrial DNA signatures.

    Science.gov (United States)

    Storey, Alice A; Athens, J Stephen; Bryant, David; Carson, Mike; Emery, Kitty; deFrance, Susan; Higham, Charles; Huynen, Leon; Intoh, Michiko; Jones, Sharyn; Kirch, Patrick V; Ladefoged, Thegn; McCoy, Patrick; Morales-Muñiz, Arturo; Quiroz, Daniel; Reitz, Elizabeth; Robins, Judith; Walter, Richard; Matisoo-Smith, Elizabeth

    2012-01-01

    Data from morphology, linguistics, history, and archaeology have all been used to trace the dispersal of chickens from Asian domestication centers to their current global distribution. Each provides a unique perspective which can aid in the reconstruction of prehistory. This study expands on previous investigations by adding a temporal component from ancient DNA and, in some cases, direct dating of bones of individual chickens from a variety of sites in Europe, the Pacific, and the Americas. The results from the ancient DNA analyses of forty-eight archaeologically derived chicken bones provide support for archaeological hypotheses about the prehistoric human transport of chickens. Haplogroup E mtDNA signatures have been amplified from directly dated samples originating in Europe at 1000 B.P. and in the Pacific at 3000 B.P. indicating multiple prehistoric dispersals from a single Asian centre. These two dispersal pathways converged in the Americas where chickens were introduced both by Polynesians and later by Europeans. The results of this study also highlight the inappropriate application of the small stretch of D-loop, traditionally amplified for use in phylogenetic studies, to understanding discrete episodes of chicken translocation in the past. The results of this study lead to the proposal of four hypotheses which will require further scrutiny and rigorous future testing.

  10. Differential Nuclear and Mitochondrial DNA Preservation in Post-Mortem Teeth with Implications for Forensic and Ancient DNA Studies

    Science.gov (United States)

    Higgins, Denice; Rohrlach, Adam B.; Kaidonis, John; Townsend, Grant; Austin, Jeremy J.

    2015-01-01

    Major advances in genetic analysis of skeletal remains have been made over the last decade, primarily due to improvements in post-DNA-extraction techniques. Despite this, a key challenge for DNA analysis of skeletal remains is the limited yield of DNA recovered from these poorly preserved samples. Enhanced DNA recovery by improved sampling and extraction techniques would allow further advancements. However, little is known about the post-mortem kinetics of DNA degradation and whether the rate of degradation varies between nuclear and mitochondrial DNA or across different skeletal tissues. This knowledge, along with information regarding ante-mortem DNA distribution within skeletal elements, would inform sampling protocols facilitating development of improved extraction processes. Here we present a combined genetic and histological examination of DNA content and rates of DNA degradation in the different tooth tissues of 150 human molars over short-medium post-mortem intervals. DNA was extracted from coronal dentine, root dentine, cementum and pulp of 114 teeth via a silica column method and the remaining 36 teeth were examined histologically. Real time quantification assays based on two nuclear DNA fragments (67 bp and 156 bp) and one mitochondrial DNA fragment (77 bp) showed nuclear and mitochondrial DNA degraded exponentially, but at different rates, depending on post-mortem interval and soil temperature. In contrast to previous studies, we identified differential survival of nuclear and mtDNA in different tooth tissues. Futhermore histological examination showed pulp and dentine were rapidly affected by loss of structural integrity, and pulp was completely destroyed in a relatively short time period. Conversely, cementum showed little structural change over the same time period. Finally, we confirm that targeted sampling of cementum from teeth buried for up to 16 months can provide a reliable source of nuclear DNA for STR-based genotyping using standard

  11. Low Mitochondrial DNA Diversity in an Ancient Population from China: Insight into Social Organization at the Fujia Site.

    Science.gov (United States)

    Dong, Yu; Li, Chunxiang; Luan, Fengshi; Li, Zhenguang; Li, Hongjie; Cui, Yinqiu; Zhou, Hui; Malhi, Ripan S

    2015-01-01

    To gain insight into the social organization of a population associated with the Dawenkou period, we performed ancient DNA analysis of 18 individuals from human remains from the Fujia site in Shandong Province, China. Directly radiocarbon dated to 4800-4500 cal BP, the Fujia site is assumed to be associated with a transitional phase from matrilineal clans to patrilineal monogamous families. Our results reveal a low mitochondrial DNA diversity from the site and population. Combined with Y chromosome data, the pattern observed at the Fujia site is most consistent with a matrilineal community. The patterns also suggest that the bond of marriage was de-emphasized compared with the bonds of descent at Fujia.

  12. Mitogenomic analyses from ancient DNA

    DEFF Research Database (Denmark)

    Paijmans, Johanna L. A.; Gilbert, Tom; Hofreiter, Michael

    2013-01-01

    The analysis of ancient DNA is playing an increasingly important role in conservation genetic, phylogenetic and population genetic analyses, as it allows incorporating extinct species into DNA sequence trees and adds time depth to population genetics studies. For many years, these types of DNA...... analyses (whether using modern or ancient DNA) were largely restricted to the analysis of short fragments of the mitochondrial genome. However, due to many technological advances during the past decade, a growing number of studies have explored the power of complete mitochondrial genome sequences...... yielded major progress with regard to both the phylogenetic positions of extinct species, as well as resolving population genetics questions in both extinct and extant species....

  13. What Is Mitochondrial DNA?

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    ... DNA What is mitochondrial DNA? What is mitochondrial DNA? Although most DNA is packaged in chromosomes within ... proteins. For more information about mitochondria and mitochondrial DNA: Molecular Expressions, a web site from the Florida ...

  14. Quantification and presence of human ancient DNA in burial place ...

    African Journals Online (AJOL)

    Quantification and presence of human ancient DNA in burial place remains of Turkey using real time polymerase chain reaction. ... A published real-time PCR assay, which allows for the combined analysis of nuclear or ancient DNA and mitochondrial DNA, was modified. This approach can be used for recovering DNA from ...

  15. Mitochondrial phylogenomics of modern and ancient equids.

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    Vilstrup, Julia T; Seguin-Orlando, Andaine; Stiller, Mathias; Ginolhac, Aurelien; Raghavan, Maanasa; Nielsen, Sandra C A; Weinstock, Jacobo; Froese, Duane; Vasiliev, Sergei K; Ovodov, Nikolai D; Clary, Joel; Helgen, Kristofer M; Fleischer, Robert C; Cooper, Alan; Shapiro, Beth; Orlando, Ludovic

    2013-01-01

    The genus Equus is richly represented in the fossil record, yet our understanding of taxonomic relationships within this genus remains limited. To estimate the phylogenetic relationships among modern horses, zebras, asses and donkeys, we generated the first data set including complete mitochondrial sequences from all seven extant lineages within the genus Equus. Bayesian and Maximum Likelihood phylogenetic inference confirms that zebras are monophyletic within the genus, and the Plains and Grevy's zebras form a well-supported monophyletic group. Using ancient DNA techniques, we further characterize the complete mitochondrial genomes of three extinct equid lineages (the New World stilt-legged horses, NWSLH; the subgenus Sussemionus; and the Quagga, Equus quagga quagga). Comparisons with extant taxa confirm the NWSLH as being part of the caballines, and the Quagga and Plains zebras as being conspecific. However, the evolutionary relationships among the non-caballine lineages, including the now-extinct subgenus Sussemionus, remain unresolved, most likely due to extremely rapid radiation within this group. The closest living outgroups (rhinos and tapirs) were found to be too phylogenetically distant to calibrate reliable molecular clocks. Additional mitochondrial genome sequence data, including radiocarbon dated ancient equids, will be required before revisiting the exact timing of the lineage radiation leading up to modern equids, which for now were found to have possibly shared a common ancestor as far as up to 4 Million years ago (Mya).

  16. Mitochondrial Phylogenomics of Modern and Ancient Equids

    Science.gov (United States)

    Vilstrup, Julia T.; Seguin-Orlando, Andaine; Stiller, Mathias; Ginolhac, Aurelien; Raghavan, Maanasa; Nielsen, Sandra C. A.; Weinstock, Jacobo; Froese, Duane; Vasiliev, Sergei K.; Ovodov, Nikolai D.; Clary, Joel; Helgen, Kristofer M.; Fleischer, Robert C.; Cooper, Alan; Shapiro, Beth; Orlando, Ludovic

    2013-01-01

    The genus Equus is richly represented in the fossil record, yet our understanding of taxonomic relationships within this genus remains limited. To estimate the phylogenetic relationships among modern horses, zebras, asses and donkeys, we generated the first data set including complete mitochondrial sequences from all seven extant lineages within the genus Equus. Bayesian and Maximum Likelihood phylogenetic inference confirms that zebras are monophyletic within the genus, and the Plains and Grevy’s zebras form a well-supported monophyletic group. Using ancient DNA techniques, we further characterize the complete mitochondrial genomes of three extinct equid lineages (the New World stilt-legged horses, NWSLH; the subgenus Sussemionus; and the Quagga, Equus quagga quagga). Comparisons with extant taxa confirm the NWSLH as being part of the caballines, and the Quagga and Plains zebras as being conspecific. However, the evolutionary relationships among the non-caballine lineages, including the now-extinct subgenus Sussemionus, remain unresolved, most likely due to extremely rapid radiation within this group. The closest living outgroups (rhinos and tapirs) were found to be too phylogenetically distant to calibrate reliable molecular clocks. Additional mitochondrial genome sequence data, including radiocarbon dated ancient equids, will be required before revisiting the exact timing of the lineage radiation leading up to modern equids, which for now were found to have possibly shared a common ancestor as far as up to 4 Million years ago (Mya). PMID:23437078

  17. Mitochondrial phylogenomics of modern and ancient equids.

    Directory of Open Access Journals (Sweden)

    Julia T Vilstrup

    Full Text Available The genus Equus is richly represented in the fossil record, yet our understanding of taxonomic relationships within this genus remains limited. To estimate the phylogenetic relationships among modern horses, zebras, asses and donkeys, we generated the first data set including complete mitochondrial sequences from all seven extant lineages within the genus Equus. Bayesian and Maximum Likelihood phylogenetic inference confirms that zebras are monophyletic within the genus, and the Plains and Grevy's zebras form a well-supported monophyletic group. Using ancient DNA techniques, we further characterize the complete mitochondrial genomes of three extinct equid lineages (the New World stilt-legged horses, NWSLH; the subgenus Sussemionus; and the Quagga, Equus quagga quagga. Comparisons with extant taxa confirm the NWSLH as being part of the caballines, and the Quagga and Plains zebras as being conspecific. However, the evolutionary relationships among the non-caballine lineages, including the now-extinct subgenus Sussemionus, remain unresolved, most likely due to extremely rapid radiation within this group. The closest living outgroups (rhinos and tapirs were found to be too phylogenetically distant to calibrate reliable molecular clocks. Additional mitochondrial genome sequence data, including radiocarbon dated ancient equids, will be required before revisiting the exact timing of the lineage radiation leading up to modern equids, which for now were found to have possibly shared a common ancestor as far as up to 4 Million years ago (Mya.

  18. Nuclear counterparts of the cytoplasmic mitochondrial 12S rRNA gene: a problem of ancient DNA and molecular phylogenies

    NARCIS (Netherlands)

    van der Kuyl, A. C.; Kuiken, C. L.; Dekker, J. T.; Perizonius, W. R.; Goudsmit, J.

    1995-01-01

    Monkey mummy bones and teeth originating from the North Saqqara Baboon Galleries (Egypt), soft tissue from a mummified baboon in a museum collection, and nineteenth/twentieth-century skin fragments from mangabeys were used for DNA extraction and PCR amplification of part of the mitochondrial 12S

  19. Authenticity in ancient DNA studies

    DEFF Research Database (Denmark)

    Gilbert, M Thomas P; Willerslev, Eske

    2006-01-01

    Ancient DNA studies represent a powerful tool that can be used to obtain genetic insights into the past. However, despite the publication of large numbers of apparently successful ancient DNA studies, a number of problems exist with the field that are often ignored. Therefore, questions exist as ...

  20. Ancient human mitochondrial DNA and radiocarbon analysis of archived quids from the Mule Spring Rockshelter, Nevada, USA.

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    Scott D Hamilton-Brehm

    Full Text Available Chewed and expectorated quids, indigestible stringy fibers from the roasted inner pulp of agave or yucca root, have proven resilient over long periods of time in dry cave environments and correspondingly, although little studied, are common in archaeological archives. In the late 1960s, thousands of quids were recovered from Mule Spring Rockshelter (Nevada, USA deposits and stored without consideration to DNA preservation in a museum collection, remaining unstudied for over fifty years. To assess the utility of these materials as repositories for genetic information about past inhabitants of the region and their movements, twenty-one quids were selected from arbitrary excavation depths for detailed analysis. Human mitochondrial DNA sequences from the quids were amplified by PCR and screened for diagnostic single nucleotide polymorphisms. Most detected single nucleotide polymorphisms were consistent with recognized Native American haplogroup subclades B2a5, B2i1, C1, C1c, C1c2, and D1; with the majority of the sample set consistent with subclades C1, C1c, and C1c2. In parallel with the DNA analysis, each quid was radiocarbon dated, revealing a time-resolved pattern of occupancy from 347 to 977 calibrated years before present. In particular, this dataset reveals strong evidence for the presence of haplogroup C1/C1c at the Southwestern edge of the US Great Basin from ~670 to 980 cal YBP, which may temporally correspond with the beginnings of the so-called Numic Spread into the region. The research described here demonstrates an approach which combines targeted DNA analysis with radiocarbon age dating; thus enabling the genetic analysis of archaeological materials of uncertain stratigraphic context. Here we present a survey of the maternal genetic profiles from people who used the Mule Spring Rockshelter and the historic timing of their utilization of a key natural resource.

  1. Analysis of ancient human mitochondrial DNA from the Xiaohe cemetery: insights into prehistoric population movements in the Tarim Basin, China.

    Science.gov (United States)

    Li, Chunxiang; Ning, Chao; Hagelberg, Erika; Li, Hongjie; Zhao, Yongbin; Li, Wenying; Abuduresule, Idelisi; Zhu, Hong; Zhou, Hui

    2015-07-08

    The Tarim Basin in western China, known for its amazingly well-preserved mummies, has been for thousands of years an important crossroad between the eastern and western parts of Eurasia. Despite its key position in communications and migration, and highly diverse peoples, languages and cultures, its prehistory is poorly understood. To shed light on the origin of the populations of the Tarim Basin, we analysed mitochondrial DNA polymorphisms in human skeletal remains excavated from the Xiaohe cemetery, used by the local community between 4000 and 3500 years before present, and possibly representing some of the earliest settlers. Xiaohe people carried a wide variety of maternal lineages, including West Eurasian lineages H, K, U5, U7, U2e, T, R*, East Eurasian lineages B, C4, C5, D, G2a and Indian lineage M5. Our results indicate that the people of the Tarim Basin had a diverse maternal ancestry, with origins in Europe, central/eastern Siberia and southern/western Asia. These findings, together with information on the cultural context of the Xiaohe cemetery, can be used to test contrasting hypotheses of route of settlement into the Tarim Basin.

  2. Fossil avian eggshell preserves ancient DNA

    DEFF Research Database (Denmark)

    Oskam, Charlotte L; Haile, James Seymour; McLay, Emma

    2010-01-01

    Owing to exceptional biomolecule preservation, fossil avian eggshell has been used extensively in geochronology and palaeodietary studies. Here, we show, to our knowledge, for the first time that fossil eggshell is a previously unrecognized source of ancient DNA (aDNA). We describe the successful...... isolation and amplification of DNA from fossil eggshell up to 19 ka old. aDNA was successfully characterized from eggshell obtained from New Zealand (extinct moa and ducks), Madagascar (extinct elephant birds) and Australia (emu and owl). Our data demonstrate excellent preservation of the nucleic acids......, evidenced by retrieval of both mitochondrial and nuclear DNA from many of the samples. Using confocal microscopy and quantitative PCR, this study critically evaluates approaches to maximize DNA recovery from powdered eggshell. Our quantitative PCR experiments also demonstrate that moa eggshell has...

  3. Replicating animal mitochondrial DNA

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    Emily A. McKinney

    2013-01-01

    Full Text Available The field of mitochondrial DNA (mtDNA replication has been experiencing incredible progress in recent years, and yet little is certain about the mechanism(s used by animal cells to replicate this plasmid-like genome. The long-standing strand-displacement model of mammalian mtDNA replication (for which single-stranded DNA intermediates are a hallmark has been intensively challenged by a new set of data, which suggests that replication proceeds via coupled leading-and lagging-strand synthesis (resembling bacterial genome replication and/or via long stretches of RNA intermediates laid on the mtDNA lagging-strand (the so called RITOLS. The set of proteins required for mtDNA replication is small and includes the catalytic and accessory subunits of DNA polymerase y, the mtDNA helicase Twinkle, the mitochondrial single-stranded DNA-binding protein, and the mitochondrial RNA polymerase (which most likely functions as the mtDNA primase. Mutations in the genes coding for the first three proteins are associated with human diseases and premature aging, justifying the research interest in the genetic, biochemical and structural properties of the mtDNA replication machinery. Here we summarize these properties and discuss the current models of mtDNA replication in animal cells.

  4. Ancient DNA from marine mammals

    DEFF Research Database (Denmark)

    Foote, Andrew David; Hofreiter, Michael; Morin, Philip A.

    2012-01-01

    such as bone, tooth, baleen, skin, fur, whiskers and scrimshaw using ancient DNA (aDNA) approaches provide an oppor- tunity for investigating such changes over evolutionary and ecological timescales. Here, we review the application of aDNA techniques to the study of marine mammals. Most of the studies have...... focused on detecting changes in genetic diversity following periods of exploitation and environmental change. To date, these studies have shown that even small sample sizes can provide useful information on historical genetic diversity. Ancient DNA has also been used in investigations of changes...... in distribution and range of marine mammal species; we review these studies and discuss the limitations of such ‘presence only’ studies. Combining aDNA data with stable isotopes can provide further insights into changes in ecology and we review past studies and suggest future potential applications. We also...

  5. Using Ancient DNA to Understand Evolutionary and Ecological Processes

    DEFF Research Database (Denmark)

    Orlando, Ludovic Antoine Alexandre; Cooper, Alan

    2014-01-01

    Ancient DNA provides a unique means to record genetic change through time and directly observe evolutionary and ecological processes. Although mostly based on mitochondrial DNA, the increasing availability of genomic sequences is leading to unprecedented levels of resolution. Temporal studies of ...

  6. Ancient mitochondrial DNA reveals convergent evolution of giant short-faced bears (Tremarctinae) in North and South America.

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    Mitchell, Kieren J; Bray, Sarah C; Bover, Pere; Soibelzon, Leopoldo; Schubert, Blaine W; Prevosti, Francisco; Prieto, Alfredo; Martin, Fabiana; Austin, Jeremy J; Cooper, Alan

    2016-04-01

    The Tremarctinae are a subfamily of bears endemic to the New World, including two of the largest terrestrial mammalian carnivores that have ever lived: the giant, short-faced bears Arctodus simus from North America and Arctotherium angustidens from South America (greater than or equal to 1000 kg). Arctotherium angustidens became extinct during the Early Pleistocene, whereas Arctodus simus went extinct at the very end of the Pleistocene. The only living tremarctine is the spectacled bear (Tremarctos ornatus), a largely herbivorous bear that is today only found in South America. The relationships among the spectacled bears (Tremarctos), South American short-faced bears (Arctotherium) and North American short-faced bears (Arctodus) remain uncertain. In this study, we sequenced a mitochondrial genome from an Arctotherium femur preserved in a Chilean cave. Our molecular phylogenetic analyses revealed that the South American short-faced bears were more closely related to the extant South American spectacled bear than to the North American short-faced bears. This result suggests striking convergent evolution of giant forms in the two groups of short-faced bears (Arctodus and Arctotherium), potentially as an adaptation to dominate competition for megafaunal carcasses. © 2016 The Author(s).

  7. Comparing ancient DNA preservation in petrous bone and tooth cementum

    DEFF Research Database (Denmark)

    Hansen, Henrik B.; Damgaard, Peter de Barros; Margaryan, Ashot

    2017-01-01

    Large-scale genomic analyses of ancient human populations have become feasible partly due to refined sampling methods. The inner part of petrous bones and the cementum layer in teeth roots are currently recognized as the best substrates for such research. We present a comparative analysis of DNA...... to thymine deamination damage and lower proportions of mitochondrial/nuclear DNA in petrous bone compared to tooth cementum. Lastly, we show that petrous bones from ancient cremated individuals contain no measurable levels of authentic human DNA. Based on these findings we discuss the pros and cons...

  8. Ancient DNA sequences point to a large loss of mitochondrial genetic diversity in the saiga antelope (Saiga tatarica) since the Pleistocene

    DEFF Research Database (Denmark)

    Campos, Paula; Kristensen, Tommy; Orlando, Ludovic Antoine Alexandre

    2010-01-01

    of the Soviet Union, after which its populations were reduced by over 95%. We have analysed the mitochondrial control region sequence variation of 27 ancient and 38 modern specimens, to assay how the species' genetic diversity has changed since the Pleistocene. Phylogenetic analyses reveal the existence of two...... well-supported, and clearly distinct, clades of saiga. The first, spanning a time range from >49,500 (14) C ybp to the present, comprises all the modern specimens and ancient samples from the Northern Urals, Middle Urals and Northeast Yakutia. The second clade is exclusive to the Northern Urals...... and includes samples dating from between 40,400 to 10,250 (14) C ybp. Current genetic diversity is much lower than that present during the Pleistocene, an observation that data modelling using serial coalescent indicates cannot be explained by genetic drift in a population of constant size. Approximate...

  9. Ancient and modern environmental DNA

    Science.gov (United States)

    Pedersen, Mikkel Winther; Overballe-Petersen, Søren; Ermini, Luca; Sarkissian, Clio Der; Haile, James; Hellstrom, Micaela; Spens, Johan; Thomsen, Philip Francis; Bohmann, Kristine; Cappellini, Enrico; Schnell, Ida Bærholm; Wales, Nathan A.; Carøe, Christian; Campos, Paula F.; Schmidt, Astrid M. Z.; Gilbert, M. Thomas P.; Hansen, Anders J.; Orlando, Ludovic; Willerslev, Eske

    2015-01-01

    DNA obtained from environmental samples such as sediments, ice or water (environmental DNA, eDNA), represents an important source of information on past and present biodiversity. It has revealed an ancient forest in Greenland, extended by several thousand years the survival dates for mainland woolly mammoth in Alaska, and pushed back the dates for spruce survival in Scandinavian ice-free refugia during the last glaciation. More recently, eDNA was used to uncover the past 50 000 years of vegetation history in the Arctic, revealing massive vegetation turnover at the Pleistocene/Holocene transition, with implications for the extinction of megafauna. Furthermore, eDNA can reflect the biodiversity of extant flora and fauna, both qualitatively and quantitatively, allowing detection of rare species. As such, trace studies of plant and vertebrate DNA in the environment have revolutionized our knowledge of biogeography. However, the approach remains marred by biases related to DNA behaviour in environmental settings, incomplete reference databases and false positive results due to contamination. We provide a review of the field. PMID:25487334

  10. Statistical guidelines for detecting past population shifts using ancient DNA

    DEFF Research Database (Denmark)

    Mourier, Tobias; Ho, Simon Y. W.; Gilbert, Tom

    2012-01-01

    Populations carry a genetic signal of their demographic past, providing an opportunity for investigating the processes that shaped their evolution. Our ability to infer population histories can be enhanced by including ancient DNA data. Using serial-coalescent simulations and a range of both...... quantitative and temporal sampling schemes, we test the power of ancient mitochondrial sequences and nuclear single-nucleotide polymorphisms (SNPs) to detect past population bottlenecks. Within our simulated framework, mitochondrial sequences have only limited power to detect subtle bottlenecks and/or fast...... results provide useful guidelines for scaling sampling schemes and for optimizing our ability to infer past population dynamics. In addition, our results suggest that many ancient DNA studies may face power issues in detecting moderate demographic collapses and/or highly dynamic demographic shifts when...

  11. Mitochondrial DNA repair and aging

    International Nuclear Information System (INIS)

    Mandavilli, Bhaskar S.; Santos, Janine H.; Van Houten, Bennett

    2002-01-01

    The mitochondrial electron transport chain plays an important role in energy production in aerobic organisms and is also a significant source of reactive oxygen species that damage DNA, RNA and proteins in the cell. Oxidative damage to the mitochondrial DNA is implicated in various degenerative diseases, cancer and aging. The importance of mitochondrial ROS in age-related degenerative diseases is further strengthened by studies using animal models, Caenorhabditis elegans, Drosophila and yeast. Research in the last several years shows that mitochondrial DNA is more susceptible to various carcinogens and ROS when compared to nuclear DNA. DNA damage in mammalian mitochondria is repaired by base excision repair (BER). Studies have shown that mitochondria contain all the enzymes required for BER. Mitochondrial DNA damage, if not repaired, leads to disruption of electron transport chain and production of more ROS. This vicious cycle of ROS production and mtDNA damage ultimately leads to energy depletion in the cell and apoptosis

  12. Mitochondrial DNA repair and aging

    Energy Technology Data Exchange (ETDEWEB)

    Mandavilli, Bhaskar S.; Santos, Janine H.; Van Houten, Bennett

    2002-11-30

    The mitochondrial electron transport chain plays an important role in energy production in aerobic organisms and is also a significant source of reactive oxygen species that damage DNA, RNA and proteins in the cell. Oxidative damage to the mitochondrial DNA is implicated in various degenerative diseases, cancer and aging. The importance of mitochondrial ROS in age-related degenerative diseases is further strengthened by studies using animal models, Caenorhabditis elegans, Drosophila and yeast. Research in the last several years shows that mitochondrial DNA is more susceptible to various carcinogens and ROS when compared to nuclear DNA. DNA damage in mammalian mitochondria is repaired by base excision repair (BER). Studies have shown that mitochondria contain all the enzymes required for BER. Mitochondrial DNA damage, if not repaired, leads to disruption of electron transport chain and production of more ROS. This vicious cycle of ROS production and mtDNA damage ultimately leads to energy depletion in the cell and apoptosis.

  13. A Spatio-Temporal Analysis of Mitochondrial DNA Haplogroup I

    Directory of Open Access Journals (Sweden)

    Revesz Peter Z.

    2016-01-01

    Full Text Available The recent recovery of ancient DNA from a growing number of human samples shows that mitochondrial DNA haplogroup I was introduced to Europe after the end of the Last Glacial Maximum. This paper provides a spatio-temporal analysis of the various subhaplogroups of mitochondrial DNA I. The study suggests that haplogroup I diversified into haplogroups I1, I2’3, I4 and I5 at specific regions in Eurasia and then spread southward to Crete and Egypt.

  14. Geologically ancient DNA: fact or artefact?

    DEFF Research Database (Denmark)

    Hebsgaard, Martin Bay; Phillips, Matthew J.; Willerslev, Eske

    2005-01-01

    Studies continue to report ancient DNA sequences and viable microbial cells that are many millions of years old. In this paper we evaluate some of the most extravagant claims of geologically ancient DNA. We conclude that although exciting, the reports suffer from inadequate experimental setup and...

  15. Cheek tooth morphology and ancient mitochondrial DNA of late Pleistocene horses from the western interior of North America: Implications for the taxonomy of North American Late Pleistocene Equus.

    Directory of Open Access Journals (Sweden)

    Christina I Barrón-Ortiz

    Full Text Available Horses were a dominant component of North American Pleistocene land mammal communities and their remains are well represented in the fossil record. Despite the abundant material available for study, there is still considerable disagreement over the number of species of Equus that inhabited the different regions of the continent and on their taxonomic nomenclature. In this study, we investigated cheek tooth morphology and ancient mtDNA of late Pleistocene Equus specimens from the Western Interior of North America, with the objective of clarifying the species that lived in this region prior to the end-Pleistocene extinction. Based on the morphological and molecular data analyzed, a caballine (Equus ferus and a non-caballine (E. conversidens species were identified from different localities across most of the Western Interior. A second non-caballine species (E. cedralensis was recognized from southern localities based exclusively on the morphological analyses of the cheek teeth. Notably the separation into caballine and non-caballine species was observed in the Bayesian phylogenetic analysis of ancient mtDNA as well as in the geometric morphometric analyses of the upper and lower premolars. Teeth morphologically identified as E. conversidens that yielded ancient mtDNA fall within the New World stilt-legged clade recognized in previous studies and this is the name we apply to this group. Geographic variation in morphology in the caballine species is indicated by statistically different occlusal enamel patterns in the specimens from Bluefish Caves, Yukon Territory, relative to the specimens from the other geographic regions. Whether this represents ecomorphological variation and/or a certain degree of geographic and genetic isolation of these Arctic populations requires further study.

  16. Genetic continuity after the collapse of the Wari empire: mitochondrial DNA profiles from Wari and post-Wari populations in the ancient Andes.

    Science.gov (United States)

    Kemp, Brian M; Tung, Tiffiny A; Summar, Marshall L

    2009-09-01

    The Wari empire flourished in the central, highland Peruvian Andes from AD 600-1000, and although the events that led to its demise are unknown, archaeological evidence indicates that Wari control waned at the end of the first millennium. Here, we test the hypothesis that, despite the major shift in social and political organization at the fall of the Wari empire, the mitochondrial DNA (mtDNA) composition of populations from the Ayacucho Basin, the former imperial heartland of the empire, remained essentially unchanged. Results show that mtDNA haplogroup frequencies among the Wari and post-Wari groups differ, but the difference is not statistically significant (chi2 = 5.886, df = 3, P = 0.1172). This is the first study in the Andes to use haplotypic data to evaluate the observed genetic distance between two temporally distinct prehispanic populations (F(ST) = 0.029) against modeled expectations of four possible evolutionary scenarios. None of these simulations allowed the rejection of continuity. In total, at both the haplogroup and haplotype levels these data do not allow us to reject the hypothesis that post-Wari individuals sampled in this study are the maternal descendants of those sampled from the Wari era site of Conchopata. However, genetic homogeneity in the mitochondrial gene pool, as seen in the late prehispanic southern Andes, may also characterize our study region. But, prior to this research, this was unknown. If our new data show mtDNA homogeneity, then this could limit the detection of female migration if, in fact, it occurred. Nonetheless, the novel mtDNA data presented here currently do not support the hypothesis that there was an influx of genetically distinct females into the former Wari heartland after the Wari collapse. Copyright 2009 Wiley-Liss, Inc.

  17. Assessing the fidelity of ancient DNA sequences amplified from nuclear genes

    DEFF Research Database (Denmark)

    Binladen, Jonas; Wiuf, Carsten Henrik; Gilbert, M. Thomas P.

    2006-01-01

    To date, the field of ancient DNA has relied almost exclusively on mitochondrial DNA (mtDNA) sequences. However, a number of recent studies have reported the successful recovery of ancient nuclear DNA (nuDNA) sequences, thereby allowing the characterization of genetic loci directly involved...... in phenotypic traits of extinct taxa. It is well documented that postmortem damage in ancient mtDNA can lead to the generation of artifactual sequences. However, as yet no one has thoroughly investigated the damage spectrum in ancient nuDNA. By comparing clone sequences from 23 fossil specimens, recovered from...... adenine), respectively. Type 2 transitions are by far the most dominant and increase relative to those of type 1 with damage load. The results suggest that the deamination of cytosine (and 5-methyl cytosine) to uracil (and thymine) is the main cause of miscoding lesions in both ancient mtDNA and nu...

  18. Paleo-Environmental Reconstruction Using Ancient DNA

    DEFF Research Database (Denmark)

    Pedersen, Mikkel Winther

    The aim of this thesis has been to investigate and expand the methodology and applicability for using ancient DNA deposited in lake sediments to detect and determine its genetic sources for paleo-environmental reconstruction. The aim was furthermore to put this tool into an applicable context...... solving other scientifically interesting questions. Still in its childhood, ancient environmental DNA research has a large potential for still developing, improving and discovering its possibilities and limitations in different environments and for identifying various organisms, both in terms...... research on ancient and modern environmental DNA (Paper 1), secondly by setting up a comparative study (Paper 2) to investigate how an ancient plant DNA (mini)-barcode can reflect other traditional methods (e.g. pollen and macrofossils) for reconstructing floristic history. In prolongation of the results...

  19. Damage and repair of ancient DNA

    DEFF Research Database (Denmark)

    Mitchell, David; Willerslev, Eske; Hansen, Anders

    2005-01-01

    degradation, these studies are limited to species that lived within the past 10(4)-10(5) years (Late Pleistocene), although DNA sequences from 10(6) years have been reported. Ancient DNA (aDNA) has been used to study phylogenetic relationships of protists, fungi, algae, plants, and higher eukaryotes...... such as extinct horses, cave bears, the marsupial wolf, the moa, and Neanderthal. In the past few years, this technology has been extended to the study of infectious disease in ancient Egyptian and South American mummies, the dietary habits of ancient animals, and agricultural practices and population dynamics......, and extensive degradation. In the course of this review, we will discuss the current aDNA literature describing the importance of aDNA studies as they relate to important biological questions and the difficulties associated with extracting useful information from highly degraded and damaged substrates derived...

  20. Mitochondrial DNA variation in the Viking age population of Norway

    OpenAIRE

    Krzewińska, Maja; Bjørnstad, Gro; Skoglund, Pontus; Olason, Pall Isolfur; Bill, Jan; Götherström, Anders; Hagelberg, Erika

    2015-01-01

    The medieval Norsemen or Vikings had an important biological and cultural impact on many parts of Europe through raids, colonization and trade, from about AD 793 to 1066. To help understand the genetic affinities of the ancient Norsemen, and their genetic contribution to the gene pool of other Europeans, we analysed DNA markers in Late Iron Age skeletal remains from Norway. DNA was extracted from 80 individuals, and mitochondrial DNA polymorphisms were detected by next-generation sequencing. ...

  1. Maintaining ancient organelles: mitochondrial biogenesis and maturation.

    Science.gov (United States)

    Vega, Rick B; Horton, Julie L; Kelly, Daniel P

    2015-05-22

    The ultrastructure of the cardiac myocyte is remarkable for the high density of mitochondria tightly packed between sarcomeres. This structural organization is designed to provide energy in the form of ATP to fuel normal pump function of the heart. A complex system comprised of regulatory factors and energy metabolic machinery, encoded by both mitochondrial and nuclear genomes, is required for the coordinate control of cardiac mitochondrial biogenesis, maturation, and high-capacity function. This process involves the action of a transcriptional regulatory network that builds and maintains the mitochondrial genome and drives the expression of the energy transduction machinery. This finely tuned system is responsive to developmental and physiological cues, as well as changes in fuel substrate availability. Deficiency of components critical for mitochondrial energy production frequently manifests as a cardiomyopathic phenotype, underscoring the requirement to maintain high respiration rates in the heart. Although a precise causative role is not clear, there is increasing evidence that perturbations in this regulatory system occur in the hypertrophied and failing heart. This review summarizes current knowledge and highlights recent advances in our understanding of the transcriptional regulatory factors and signaling networks that serve to regulate mitochondrial biogenesis and function in the mammalian heart. © 2015 American Heart Association, Inc.

  2. Comparing Ancient DNA Preservation in Petrous Bone and Tooth Cementum.

    Directory of Open Access Journals (Sweden)

    Henrik B Hansen

    Full Text Available Large-scale genomic analyses of ancient human populations have become feasible partly due to refined sampling methods. The inner part of petrous bones and the cementum layer in teeth roots are currently recognized as the best substrates for such research. We present a comparative analysis of DNA preservation in these two substrates obtained from the same human skulls, across a range of different ages and preservation environments. Both substrates display significantly higher endogenous DNA content (average of 16.4% and 40.0% for teeth and petrous bones, respectively than parietal skull bone (average of 2.2%. Despite sample-to-sample variation, petrous bone overall performs better than tooth cementum (p = 0.001. This difference, however, is driven largely by a cluster of viking skeletons from one particular locality, showing relatively poor molecular tooth preservation (<10% endogenous DNA. In the remaining skeletons there is no systematic difference between the two substrates. A crude preservation (good/bad applied to each sample prior to DNA-extraction predicted the above/below 10% endogenous DNA threshold in 80% of the cases. Interestingly, we observe signficantly higher levels of cytosine to thymine deamination damage and lower proportions of mitochondrial/nuclear DNA in petrous bone compared to tooth cementum. Lastly, we show that petrous bones from ancient cremated individuals contain no measurable levels of authentic human DNA. Based on these findings we discuss the pros and cons of sampling the different elements.

  3. Mitochondrial DNA and Cancer Epidemiology Workshop

    Science.gov (United States)

    A workshop to review the state-of-the science in the mitochondrial DNA field and its use in cancer epidemiology, and to develop a concept for a research initiative on mitochondrial DNA and cancer epidemiology.

  4. Mitochondrial phylogenomics of modern and ancient equids

    DEFF Research Database (Denmark)

    Mouatt, Julia Thidamarth Vilstrup; Seguin-Orlando, Andaine; Stiller, Mathias

    2013-01-01

    The genus Equus is richly represented in the fossil record, yet our understanding of taxonomic relationships within this genus remains limited. To estimate the phylogenetic relationships among modern horses, zebras, asses and donkeys, we generated the first data set including complete mitochondrial...

  5. Ancient DNA analysis of dental calculus.

    Science.gov (United States)

    Weyrich, Laura S; Dobney, Keith; Cooper, Alan

    2015-02-01

    Dental calculus (calcified tartar or plaque) is today widespread on modern human teeth around the world. A combination of soft starchy foods, changing acidity of the oral environment, genetic pre-disposition, and the absence of dental hygiene all lead to the build-up of microorganisms and food debris on the tooth crown, which eventually calcifies through a complex process of mineralisation. Millions of oral microbes are trapped and preserved within this mineralised matrix, including pathogens associated with the oral cavity and airways, masticated food debris, and other types of extraneous particles that enter the mouth. As a result, archaeologists and anthropologists are increasingly using ancient human dental calculus to explore broad aspects of past human diet and health. Most recently, high-throughput DNA sequencing of ancient dental calculus has provided valuable insights into the evolution of the oral microbiome and shed new light on the impacts of some of the major biocultural transitions on human health throughout history and prehistory. Here, we provide a brief historical overview of archaeological dental calculus research, and discuss the current approaches to ancient DNA sampling and sequencing. Novel applications of ancient DNA from dental calculus are discussed, highlighting the considerable scope of this new research field for evolutionary biology and modern medicine. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Ancient and modern environmental DNA

    DEFF Research Database (Denmark)

    Pedersen, Mikkel Winther; Overballe-Petersen, Søren; Ermini, Luca

    2015-01-01

    woolly mammoth in Alaska, and pushed back the dates for spruce survival in Scandinavian ice-free refugia during the last glaciation. More recently, eDNA was used to uncover the past 50 000 years of vegetation history in the Arctic, revealing massive vegetation turnover at the Pleistocene...

  7. Ancient bacteria show evidence of DNA repair

    DEFF Research Database (Denmark)

    Johnson, Sarah Stewart; Hebsgaard, Martin B; Christensen, Torben R

    2007-01-01

    -term survival of bacteria sealed in frozen conditions for up to one million years. Our results show evidence of bacterial survival in samples up to half a million years in age, making this the oldest independently authenticated DNA to date obtained from viable cells. Additionally, we find strong evidence...... geological timescales. There has been no direct evidence in ancient microbes for the most likely mechanism, active DNA repair, or for the metabolic activity necessary to sustain it. In this paper, we couple PCR and enzymatic treatment of DNA with direct respiration measurements to investigate long...... that this long-term survival is closely tied to cellular metabolic activity and DNA repair that over time proves to be superior to dormancy as a mechanism in sustaining bacteria viability....

  8. Minisequencing mitochondrial DNA pathogenic mutations

    Directory of Open Access Journals (Sweden)

    Carracedo Ángel

    2008-04-01

    Full Text Available Abstract Background There are a number of well-known mutations responsible of common mitochondrial DNA (mtDNA diseases. In order to overcome technical problems related to the analysis of complete mtDNA genomes, a variety of different techniques have been proposed that allow the screening of coding region pathogenic mutations. Methods We here propose a minisequencing assay for the analysis of mtDNA mutations. In a single reaction, we interrogate a total of 25 pathogenic mutations distributed all around the whole mtDNA genome in a sample of patients suspected for mtDNA disease. Results We have detected 11 causal homoplasmic mutations in patients suspected for Leber disease, which were further confirmed by standard automatic sequencing. Mutations m.11778G>A and m.14484T>C occur at higher frequency than expected by change in the Galician (northwest Spain patients carrying haplogroup J lineages (Fisher's Exact test, P-value Conclusion We here developed a minisequencing genotyping method for the screening of the most common pathogenic mtDNA mutations which is simple, fast, and low-cost. The technique is robust and reproducible and can easily be implemented in standard clinical laboratories.

  9. Mitochondrial DNA variation in the Viking age population of Norway.

    Science.gov (United States)

    Krzewińska, Maja; Bjørnstad, Gro; Skoglund, Pontus; Olason, Pall Isolfur; Bill, Jan; Götherström, Anders; Hagelberg, Erika

    2015-01-19

    The medieval Norsemen or Vikings had an important biological and cultural impact on many parts of Europe through raids, colonization and trade, from about AD 793 to 1066. To help understand the genetic affinities of the ancient Norsemen, and their genetic contribution to the gene pool of other Europeans, we analysed DNA markers in Late Iron Age skeletal remains from Norway. DNA was extracted from 80 individuals, and mitochondrial DNA polymorphisms were detected by next-generation sequencing. The sequences of 45 ancient Norwegians were verified as genuine through the identification of damage patterns characteristic of ancient DNA. The ancient Norwegians were genetically similar to previously analysed ancient Icelanders, and to present-day Shetland and Orkney Islanders, Norwegians, Swedes, Scots, English, German and French. The Viking Age population had higher frequencies of K*, U*, V* and I* haplogroups than their modern counterparts, but a lower proportion of T* and H* haplogroups. Three individuals carried haplotypes that are rare in Norway today (U5b1b1, Hg A* and an uncommon variant of H*). Our combined analyses indicate that Norse women were important agents in the overseas expansion and settlement of the Vikings, and that women from the Orkneys and Western Isles contributed to the colonization of Iceland. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  10. Successful enrichment and recovery of whole mitochondrial genomes from ancient human dental calculus.

    Science.gov (United States)

    Ozga, Andrew T; Nieves-Colón, Maria A; Honap, Tanvi P; Sankaranarayanan, Krithivasan; Hofman, Courtney A; Milner, George R; Lewis, Cecil M; Stone, Anne C; Warinner, Christina

    2016-06-01

    Archaeological dental calculus is a rich source of host-associated biomolecules. Importantly, however, dental calculus is more accurately described as a calcified microbial biofilm than a host tissue. As such, concerns regarding destructive analysis of human remains may not apply as strongly to dental calculus, opening the possibility of obtaining human health and ancestry information from dental calculus in cases where destructive analysis of conventional skeletal remains is not permitted. Here we investigate the preservation of human mitochondrial DNA (mtDNA) in archaeological dental calculus and its potential for full mitochondrial genome (mitogenome) reconstruction in maternal lineage ancestry analysis. Extracted DNA from six individuals at the 700-year-old Norris Farms #36 cemetery in Illinois was enriched for mtDNA using in-solution capture techniques, followed by Illumina high-throughput sequencing. Full mitogenomes (7-34×) were successfully reconstructed from dental calculus for all six individuals, including three individuals who had previously tested negative for DNA preservation in bone using conventional PCR techniques. Mitochondrial haplogroup assignments were consistent with previously published findings, and additional comparative analysis of paired dental calculus and dentine from two individuals yielded equivalent haplotype results. All dental calculus samples exhibited damage patterns consistent with ancient DNA, and mitochondrial sequences were estimated to be 92-100% endogenous. DNA polymerase choice was found to impact error rates in downstream sequence analysis, but these effects can be mitigated by greater sequencing depth. Dental calculus is a viable alternative source of human DNA that can be used to reconstruct full mitogenomes from archaeological remains. Am J Phys Anthropol 160:220-228, 2016. © 2016 The Authors American Journal of Physical Anthropology Published by Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  11. Mitochondrial DNA: A Blind Spot in Neuroepigenetics.

    Science.gov (United States)

    Manev, Hari; Dzitoyeva, Svetlana; Chen, Hu

    2012-04-01

    Neuroepigenetics, which includes nuclear DNA modifications such as 5-methylcytosine and 5-hydoxymethylcytosine and modifications of nuclear proteins such as histones, is emerging as the leading field in molecular neuroscience. Historically, a functional role for epigenetic mechanisms, including in neuroepigenetics, has been sought in the area of the regulation of nuclear transcription. However, one important compartment of mammalian cell DNA, different from nuclear but equally important for physiological and pathological processes (including in the brain), mitochondrial DNA has for the most part not had a systematic epigenetic characterization. The importance of mitochondria and mitochondrial DNA (particularly its mutations) in central nervous system physiology and pathology has long been recognized. Only recently have mechanisms of mitochondrial DNA methylation and hydroxymethylation, including the discovery of mitochondrial DNA-methyltransferases and the presence and the functionality of 5-methylcytosine and 5-hydroxymethylcytosine in mitochondrial DNA (e.g., in modifying the transcription of mitochondrial genome), been unequivocally recognized as a part of mammalian mitochondrial physiology. Here we summarize for the first time evidence supporting the existence of these mechanisms and we propose the term "mitochondrial epigenetics" to be used when referring to them. Currently, neuroepigenetics does not include mitochondrial epigenetics - a gap that we expect to close in the near future.

  12. Mitochondrial DNA mutations in human tumor cells

    OpenAIRE

    LI, HUI; HONG, ZE-HUI

    2012-01-01

    Mitochondria play significant roles in cellular energy metabolism, free radical generation and apoptosis. The dysfunction of mitochondria is correlated with the origin and progression of tumors; thus, mutations in the mitochondrial genome that affect mitochondrial function may be one of the causal factors of tumorigenesis. Although the role of mitochondrial DNA (mtDNA) mutations in carcinogenesis has been investigated extensively by various approaches, the conclusions remain controversial to ...

  13. Early history of European domestic cattle as revealed by ancient DNA.

    Science.gov (United States)

    Bollongino, R; Edwards, C J; Alt, K W; Burger, J; Bradley, D G

    2006-03-22

    We present an extensive ancient DNA analysis of mainly Neolithic cattle bones sampled from archaeological sites along the route of Neolithic expansion, from Turkey to North-Central Europe and Britain. We place this first reasonable population sample of Neolithic cattle mitochondrial DNA sequence diversity in context to illustrate the continuity of haplotype variation patterns from the first European domestic cattle to the present. Interestingly, the dominant Central European pattern, a starburst phylogeny around the modal sequence, T3, has a Neolithic origin, and the reduced diversity within this cluster in the ancient samples accords with their shorter history of post-domestic accumulation of mutation.

  14. Nucleotide sequence preservation of human mitochondrial DNA

    International Nuclear Information System (INIS)

    Monnat, R.J. Jr.; Loeb, L.A.

    1985-01-01

    Recombinant DNA techniques have been used to quantitate the amount of nucleotide sequence divergence in the mitochondrial DNA population of individual normal humans. Mitochondrial DNA was isolated from the peripheral blood lymphocytes of five normal humans and cloned in M13 mp11; 49 kilobases of nucleotide sequence information was obtained from 248 independently isolated clones from the five normal donors. Both between- and within-individual differences were identified. Between-individual differences were identified in approximately = to 1/200 nucleotides. In contrast, only one within-individual difference was identified in 49 kilobases of nucleotide sequence information. This high degree of mitochondrial nucleotide sequence homogeneity in human somatic cells is in marked contrast to the rapid evolutionary divergence of human mitochondrial DNA and suggests the existence of mechanisms for the concerted preservation of mammalian mitochondrial DNA sequences in single organisms

  15. Ancient DNA from nomads in 2500-year-old archeological sites of Pengyang, China.

    Science.gov (United States)

    Zhao, Yong-Bin; Li, Hong-Jie; Cai, Da-Wei; Li, Chun-Xiang; Zhang, Quan-Chao; Zhu, Hong; Zhou, Hui

    2010-04-01

    Six human remains (dating approximately 2500 years ago) were excavated from Pengyang, China, an area occupied by both ancient nomadic and farming people. The funerary objects found with these remains suggested they were nomads. To further confirm their ancestry, we analyzed both the maternal lineages and paternal lineages of the ancient DNA. From the mitochondrial DNA, six haplotypes were identified as three haplogroups: C, D4 and M10. The haplotype-sharing populations and phylogenetic analyses revealed that these individuals were closely associated with the ancient Xiongnu and modern northern Asians. Single-nucleotide polymorphism analysis of Y chromosomes from four male samples that were typed as haplogroup Q indicated that these people had originated in Siberia. These results show that these ancient people from Pengyang present a close genetic affinity to nomadic people, indicating that northern nomads had reached the Central Plain area of China nearly 2500 years ago.

  16. Ancient DNA and Forensics Mutual Benefits a Practical Sampling and Laboratory Guide Through a Virtual Ancient DNA Study

    Directory of Open Access Journals (Sweden)

    Jan Cemper-Kiesslich

    2014-09-01

    In this review the authors give a general overview on the field of ancient DNA analysis focussing of the potentials and limits, fields of application, requirements for samples, laboratory setup, reaction design and equipment as well as a brief outlook on current developments, future perspectives and potential cross links with associated scientific disciplines. Key words: Human DNA, Ancient DNA, Forensic DNA typing, Molecular archaeology, Application.

  17. Use of RAPD and PCR double amplification in the study of ancient DNA

    Directory of Open Access Journals (Sweden)

    F. Balzano

    2011-01-01

    Full Text Available This project analysed the DNA extracted from bones of ancient sheep which have been brought to light in Sardinian different archaeological sites. In order to better analyse this highly fragmented DNA, a double amplification technique was chosen. The first approach consisted of RAPD-PCR abd the second one in classic PCR. The RAPD-PCR amplified random fragments and allowed the production of numerous amplicons. The products of RAPD amplification have been amplified, more specifically, by the second PCR using primers for a sequence of 176 bp of mitochondrial D-loop region. These DNA fragments have been sequenced and the sequence analysis has confirmed that it belonged to Ovis aries. Consequently, this provedure can be considered a valid tool to perform amplification of degraded DNA, such as ancient DNA.

  18. Ancient pathogen DNA in human teeth and petrous bones

    DEFF Research Database (Denmark)

    Margaryan, Ashot; Hansen, Henrik B.; Rasmussen, Simon

    2018-01-01

    Recent ancient DNA (aDNA) studies of human pathogens have provided invaluable insights into their evolutionary history and prevalence in space and time. Most of these studies were based on DNA extracted from teeth or postcranial bones. In contrast, no pathogen DNA has been reported from the petro...

  19. Ancient DNA reveals traces of Iberian Neolithic and Bronze Age lineages in modern Iberian horses

    DEFF Research Database (Denmark)

    Lira, Jaime; Linderholm, Anna; Olaria, Carmen

    2010-01-01

    Iberian horses supports this suggestion. To test this hypothesis, we analysed mitochondrial DNA from 22 ancient Iberian horse remains belonging to the Neolithic, the Bronze Age and the Middle Ages, against previously published sequences. Only the medieval Iberian sequence appeared in the D1 group...... wild mares during an early Iberian domestication or restocking event, whereas the D1 group probably was introduced into Iberia in later historical times....

  20. Revising the recent evolutionary history of equids using ancient DNA.

    Science.gov (United States)

    Orlando, Ludovic; Metcalf, Jessica L; Alberdi, Maria T; Telles-Antunes, Miguel; Bonjean, Dominique; Otte, Marcel; Martin, Fabiana; Eisenmann, Véra; Mashkour, Marjan; Morello, Flavia; Prado, Jose L; Salas-Gismondi, Rodolfo; Shockey, Bruce J; Wrinn, Patrick J; Vasil'ev, Sergei K; Ovodov, Nikolai D; Cherry, Michael I; Hopwood, Blair; Male, Dean; Austin, Jeremy J; Hänni, Catherine; Cooper, Alan

    2009-12-22

    The rich fossil record of the family Equidae (Mammalia: Perissodactyla) over the past 55 MY has made it an icon for the patterns and processes of macroevolution. Despite this, many aspects of equid phylogenetic relationships and taxonomy remain unresolved. Recent genetic analyses of extinct equids have revealed unexpected evolutionary patterns and a need for major revisions at the generic, subgeneric, and species levels. To investigate this issue we examine 35 ancient equid specimens from four geographic regions (South America, Europe, Southwest Asia, and South Africa), of which 22 delivered 87-688 bp of reproducible aDNA mitochondrial sequence. Phylogenetic analyses support a major revision of the recent evolutionary history of equids and reveal two new species, a South American hippidion and a descendant of a basal lineage potentially related to Middle Pleistocene equids. Sequences from specimens assigned to the giant extinct Cape zebra, Equus capensis, formed a separate clade within the modern plain zebra species, a phenotypicically plastic group that also included the extinct quagga. In addition, we revise the currently recognized extinction times for two hemione-related equid groups. However, it is apparent that the current dataset cannot solve all of the taxonomic and phylogenetic questions relevant to the evolution of Equus. In light of these findings, we propose a rapid DNA barcoding approach to evaluate the taxonomic status of the many Late Pleistocene fossil Equidae species that have been described from purely morphological analyses.

  1. Next Generation Sequencing of Ancient DNA: Requirements, Strategies and Perspectives

    Directory of Open Access Journals (Sweden)

    Michael Knapp

    2010-07-01

    Full Text Available The invention of next-generation-sequencing has revolutionized almost all fields of genetics, but few have profited from it as much as the field of ancient DNA research. From its beginnings as an interesting but rather marginal discipline, ancient DNA research is now on its way into the centre of evolutionary biology. In less than a year from its invention next-generation-sequencing had increased the amount of DNA sequence data available from extinct organisms by several orders of magnitude. Ancient DNA  research is now not only adding a temporal aspect to evolutionary studies and allowing for the observation of evolution in real time, it also provides important data to help understand the origins of our own species. Here we review progress that has been made in next-generation-sequencing of ancient DNA over the past five years and evaluate sequencing strategies and future directions.

  2. Mitochondrial DNA sequence evolution in shorebird populations

    NARCIS (Netherlands)

    Wenink, P.W.

    1994-01-01

    This thesis describes the global molecular population structure of two shorebird species, in particular of the dunlin, Calidris alpina, by means of comparative sequence analysis of the most variable part of the mitochondrial DNA (mtDNA) genome. There are several reasons

  3. Non-destructive sampling of ancient insect DNA

    DEFF Research Database (Denmark)

    Thomsen, Philip Francis; Elias, Scott; Gilbert, Tom

    2009-01-01

    BACKGROUND: A major challenge for ancient DNA (aDNA) studies on insect remains is that sampling procedures involve at least partial destruction of the specimens. A recent extraction protocol reveals the possibility of obtaining DNA from past insect remains without causing visual morphological...... of 77-204 base pairs (-bp) in size using species-specific and general insect primers. CONCLUSION/SIGNIFICANCE: The applied non-destructive DNA extraction method shows promising potential on insect museum specimens of historical age as far back as AD 1820, but less so on the ancient permafrost......-preserved insect fossil remains tested, where DNA was obtained from samples up to ca. 26,000 years old. The non-frozen sediment DNA approach appears to have great potential for recording the former presence of insect taxa not normally preserved as macrofossils and opens new frontiers in research on ancient...

  4. Ancient mitogenomics

    DEFF Research Database (Denmark)

    Ho, Simon Y. W.; Gilbert, Tom

    2010-01-01

    the technical challenges that face researchers in the field. We catalogue the diverse sequencing methods and source materials used to obtain ancient mitogenomic sequences, summarise the associated genetic and phylogenetic studies that have been conducted, and evaluate the future prospects of the field.......The mitochondrial genome has been the traditional focus of most research into ancient DNA, owing to its high copy number and population-level variability. Despite this long-standing interest in mitochondrial DNA, it was only in 2001 that the first complete ancient mitogenomic sequences were...... obtained. As a result of various methodological developments, including the introduction of high-throughput sequencing techniques, the total number of ancient mitogenome sequences has increased rapidly over the past few years. In this review, we present a brief history of ancient mitogenomics and describe...

  5. Deoxyribonucleoside kinases in mitochondrial DNA depletion.

    Science.gov (United States)

    Saada-Reisch, Ann

    2004-10-01

    Mitochondrial DNA (mtDNA) depletion syndromes (MDS) are a heterogeneous group of mitochondrial disorders, manifested by a decreased mtDNA copy number and respiratory chain dysfunction. Primary MDS are inherited autosomally and may affect a single organ or multiple tissues. Mutated mitochondrial deoxyribonucleoside kinases; deoxyguanosine kinase (dGK) and thymidine kinase 2 (TK2), were associated with the hepatocerebral and myopathic forms of MDS respectively. dGK and TK2 are key enzymes in the mitochondrial nucleotide salvage pathway, providing the mitochondria with deoxyribonucleotides (dNP) essential for mtDNA synthesis. Although the mitochondrial dNP pool is physically separated from the cytosolic one, dNP's may still be imported through specific transport. Non-replicating tissues, where cytosolic dNP supply is down regulated, are thus particularly vulnerable to dGK and TK2 deficiency. The overlapping substrate specificity of deoxycytidine kinase (dCK) may explain the relative sparing of muscle in dGK deficiency, while low basal TK2 activity render this tissue susceptible to TK2 deficiency. The precise pathophysiological mechanisms of mtDNA depletion due to dGK and TK2 deficiencies remain to be determined, though recent findings confirm that it is attributed to imbalanced dNTP pools.

  6. Ancient DNA provides new insight into the maternal lineages and domestication of Chinese donkeys.

    Science.gov (United States)

    Han, Lu; Zhu, Songbiao; Ning, Chao; Cai, Dawei; Wang, Kai; Chen, Quanjia; Hu, Songmei; Yang, Junkai; Shao, Jing; Zhu, Hong; Zhou, Hui

    2014-11-30

    The donkey (Equus asinus) is an important domestic animal that provides a reliable source of protein and method of transportation for many human populations. However, the process of domestication and the dispersal routes of the Chinese donkey are still unclear, as donkey remains are sparse in the archaeological record and often confused with horse remains. To explore the maternal origins and dispersal route of Chinese donkeys, both mitochondrial DNA D-loop and cytochrome b gene fragments of 21 suspected donkey remains from four archaeological sites in China were amplified and sequenced. Molecular methods of species identification show that 17 specimens were donkeys and three samples had the maternal genetic signature of horses. One sample that dates to about 20,000 years before present failed to amplify. In this study, the phylogenetic analysis reveals that ancient Chinese donkeys have high mitochondrial DNA diversity and two distinct mitochondrial maternal lineages, known as the Somali and Nubian lineages. These results indicate that the maternal origin of Chinese domestic donkeys was probably related to the African wild ass, which includes the Nubian wild ass (Equus africanus africanus) and the Somali wild ass (Equus africanus somaliensis). Combined with historical records, the results of this study implied that domestic donkeys spread into west and north China before the emergence of the Han dynasty. The number of Chinese domestic donkeys had increased primarily to meet demand for the expansion of trade, and they were likely used as commodities or for shipping goods along the Silk Road during the Tang Dynasty, when the Silk Road reached its golden age. This study is the first to provide valuable ancient animal DNA evidence for early trade between African and Asian populations. The ancient DNA analysis of Chinese donkeys also sheds light on the dynamic process of the maternal origin, domestication, and dispersal route of ancient Chinese donkeys.

  7. DNA polymerase beta participates in mitochondrial DNA repair

    DEFF Research Database (Denmark)

    Sykora, P; Kanno, S; Akbari, M

    2017-01-01

    We have detected DNA polymerase beta (Polβ), known as a key nuclear base excision repair (BER) protein, in mitochondrial protein extracts derived from mammalian tissue and cells. Manipulation of the N-terminal sequence affected the amount of Polβ in the mitochondria. Using Polβ fragments, mitocho......We have detected DNA polymerase beta (Polβ), known as a key nuclear base excision repair (BER) protein, in mitochondrial protein extracts derived from mammalian tissue and cells. Manipulation of the N-terminal sequence affected the amount of Polβ in the mitochondria. Using Polβ fragments......, mitochondrial-specific protein partners were identified, with the interactors mainly functioning in DNA maintenance and mitochondrial import. Of particular interest was the identification of the proteins TWINKLE, SSBP1 and TFAM, all of which are mitochondria specific DNA effectors and are known to function...... in the nucleoid. Polβ directly interacted with, and influenced the activity of, the mitochondrial helicase TWINKLE. Human kidney cells with Polβ knock-out (KO) had higher endogenous mtDNA damage. Mitochondrial extracts derived from heterozygous Polβ mouse tissue and KO cells had lower nucleotide incorporation...

  8. Is the ancient permafrost bacteria able to keep DNA stable?

    Indian Academy of Sciences (India)

    Navya

    nucleotide substitutions per nucleotide site per year for mitochondrial DNA. DISCUSSION ... Despite the nature of mutations, we think the degree of variability in mutation rates is still an ..... Saccharomyces cerevisiae. Microbiology. 150 ...

  9. Targeted Transgenic Overexpression of Mitochondrial Thymidine Kinase (TK2) Alters Mitochondrial DNA (mtDNA) and Mitochondrial Polypeptide Abundance : Transgenic TK2, mtDNA, and Antiretrovirals

    OpenAIRE

    Hosseini, Seyed H.; Kohler, James J.; Haase, Chad P.; Tioleco, Nina; Stuart, Tami; Keebaugh, Erin; Ludaway, Tomika; Russ, Rodney; Green, Elgin; Long, Robert; Wang, Liya; Eriksson, Staffan; Lewis, William

    2007-01-01

    Mitochondrial toxicity limits nucleoside reverse transcriptase inhibitors (NRTIs) for acquired immune deficiency syndrome. NRTI triphosphates, the active moieties, inhibit human immunodeficiency virus reverse transcriptase and eukaryotic mitochondrial DNA polymerase pol-γ. NRTI phosphorylation seems to correlate with mitochondrial toxicity, but experimental evidence is lacking. Transgenic mice (TGs) with cardiac overexpression of thymidine kinase isoforms (mitochondrial TK2 and cytoplasmic TK...

  10. Targeted Transgenic Overexpression of Mitochondrial Thymidine Kinase (TK2) Alters Mitochondrial DNA (mtDNA) and Mitochondrial Polypeptide Abundance

    Science.gov (United States)

    Hosseini, Seyed H.; Kohler, James J.; Haase, Chad P.; Tioleco, Nina; Stuart, Tami; Keebaugh, Erin; Ludaway, Tomika; Russ, Rodney; Green, Elgin; Long, Robert; Wang, Liya; Eriksson, Staffan; Lewis, William

    2007-01-01

    Mitochondrial toxicity limits nucleoside reverse transcriptase inhibitors (NRTIs) for acquired immune deficiency syndrome. NRTI triphosphates, the active moieties, inhibit human immunodeficiency virus reverse transcriptase and eukaryotic mitochondrial DNA polymerase pol-γ. NRTI phosphorylation seems to correlate with mitochondrial toxicity, but experimental evidence is lacking. Transgenic mice (TGs) with cardiac overexpression of thymidine kinase isoforms (mitochondrial TK2 and cytoplasmic TK1) were used to study NRTI mitochondrial toxicity. Echocardiography and nuclear magnetic resonance imaging defined cardiac performance and structure. TK gene copy and enzyme activity, mitochondrial (mt) DNA and polypeptide abundance, succinate dehydrogenase and cytochrome oxidase histochemistry, and electron microscopy correlated with transgenesis, mitochondrial structure, and biogenesis. Antiretroviral combinations simulated therapy. Untreated hTK1 or TK2 TGs exhibited normal left ventricle mass. In TK2 TGs, cardiac TK2 gene copy doubled, activity increased 300-fold, and mtDNA abundance doubled. Abundance of the 17-kd subunit of complex I, succinate dehydrogenase histochemical activity, and cristae density increased. NRTIs increased left ventricle mass 20% in TK2 TGs. TK activity increased 3 logs in hTK1 TGs, but no cardiac phenotype resulted. NRTIs abrogated functional effects of transgenically increased TK2 activity but had no effect on TK2 mtDNA abundance. Thus, NRTI mitochondrial phosphorylation by TK2 is integral to clinical NRTI mitochondrial toxicity. PMID:17322372

  11. Mitochondrial DNA diagnosis for taeniasis and cysticercosis.

    Science.gov (United States)

    Yamasaki, Hiroshi; Nakao, Minoru; Sako, Yasuhito; Nakaya, Kazuhiro; Sato, Marcello Otake; Ito, Akira

    2006-01-01

    Molecular diagnosis for taeniasis and cysticercosis in humans on the basis of mitochondrial DNA analysis was reviewed. Development and application of three different methods, including restriction fragment length polymorphism analysis, base excision sequence scanning thymine-base analysis and multiplex PCR, were described. Moreover, molecular diagnosis of cysticerci found in specimens submitted for histopathology and the molecular detection of taeniasis using copro-DNA were discussed.

  12. Ancient DNA analysis identifies marine mollusc shells as new metagenomic archives of the past

    DEFF Research Database (Denmark)

    Der Sarkissian, Clio; Pichereau, Vianney; Dupont, Catherine

    2017-01-01

    Marine mollusc shells enclose a wealth of information on coastal organisms and their environment. Their life history traits as well as (palaeo-) environmental conditions, including temperature, food availability, salinity and pollution, can be traced through the analysis of their shell (micro...... extraction, high-throughput shotgun DNA sequencing and metagenomic analyses to marine mollusc shells spanning the last ~7,000 years. We report successful DNA extraction from shells, including a variety of ancient specimens, and find that DNA recovery is highly dependent on their biomineral structure......, carbonate layer preservation and disease state. We demonstrate positive taxonomic identification of mollusc species using a combination of mitochondrial DNA genomes, barcodes, genome-scale data and metagenomic approaches. We also find shell biominerals to contain a diversity of microbial DNA from the marine...

  13. Clinical case of Mitochondrial DNA Depletion

    Directory of Open Access Journals (Sweden)

    A. V. Degtyareva

    2017-01-01

    Full Text Available The article reports clinical case of early neonatal manifestation of a rare genetic disease – mitochondrial DNA depletion syndrome, confirmed in laboratory in Russia. Mutations of FBXL4, which encodes an orphan mitochondrial F-box protein, involved in the maintenance of mitochondrial DNA (mtDNA, ultimately leading to disruption of mtDNA replication and decreased activity of mitochondrial respiratory chain complexes. It’s a reason of abnormalities in clinically affected tissues, most of all the muscular system and the brain. In our case hydronephrosis on the right, subependimal cysts of the brain, partial intestinal obstruction accompanied by polyhydramnios were diagnosed antenatal. Baby’s condition at birth was satisfactory and worsened dramatically towards the end of the first day of life. Clinical presentation includes sepsis-like symptom complex, neonatal depression, muscular hypotonia, persistent decompensated lactic acidosis, increase in the concentration of mitochondrial markers in blood plasma and urine, and changes in the basal ganglia of the brain. Imaging of the brain by magnetic resonance imaging (MRI demonstrated global volume loss particularly the subcortical and periventricular white matter with significant abnormal signal in bilateral basal ganglia and brainstem with associated delayed myelination. Differential diagnosis was carried out with hereditary diseases that occur as a «sepsis-like» symptom complex, accompanied by lactic acidosis: a group of metabolic disorders of amino acids, organic acids, β-oxidation defects of fatty acids, respiratory mitochondrial chain disorders and glycogen storage disease. The diagnosis was confirmed after sequencing analysis of 62 mytochondrial genes by NGS (Next Generation Sequencing. Reported disease has an unfavorable prognosis, however, accurate diagnosis is very important for genetic counseling and helps prevent the re-birth of a sick child in the family.

  14. Ancient DNA analysis identifies marine mollusc shells as new metagenomic archives of the past.

    Science.gov (United States)

    Der Sarkissian, Clio; Pichereau, Vianney; Dupont, Catherine; Ilsøe, Peter C; Perrigault, Mickael; Butler, Paul; Chauvaud, Laurent; Eiríksson, Jón; Scourse, James; Paillard, Christine; Orlando, Ludovic

    2017-09-01

    Marine mollusc shells enclose a wealth of information on coastal organisms and their environment. Their life history traits as well as (palaeo-) environmental conditions, including temperature, food availability, salinity and pollution, can be traced through the analysis of their shell (micro-) structure and biogeochemical composition. Adding to this list, the DNA entrapped in shell carbonate biominerals potentially offers a novel and complementary proxy both for reconstructing palaeoenvironments and tracking mollusc evolutionary trajectories. Here, we assess this potential by applying DNA extraction, high-throughput shotgun DNA sequencing and metagenomic analyses to marine mollusc shells spanning the last ~7,000 years. We report successful DNA extraction from shells, including a variety of ancient specimens, and find that DNA recovery is highly dependent on their biomineral structure, carbonate layer preservation and disease state. We demonstrate positive taxonomic identification of mollusc species using a combination of mitochondrial DNA genomes, barcodes, genome-scale data and metagenomic approaches. We also find shell biominerals to contain a diversity of microbial DNA from the marine environment. Finally, we reconstruct genomic sequences of organisms closely related to the Vibrio tapetis bacteria from Manila clam shells previously diagnosed with Brown Ring Disease. Our results reveal marine mollusc shells as novel genetic archives of the past, which opens new perspectives in ancient DNA research, with the potential to reconstruct the evolutionary history of molluscs, microbial communities and pathogens in the face of environmental changes. Other future applications include conservation of endangered mollusc species and aquaculture management. © 2017 John Wiley & Sons Ltd.

  15. Ancient DNA reveals differences in behaviour and sociality between brown bears and extinct cave bears.

    Science.gov (United States)

    Fortes, Gloria G; Grandal-d'Anglade, Aurora; Kolbe, Ben; Fernandes, Daniel; Meleg, Ioana N; García-Vázquez, Ana; Pinto-Llona, Ana C; Constantin, Silviu; de Torres, Trino J; Ortiz, Jose E; Frischauf, Christine; Rabeder, Gernot; Hofreiter, Michael; Barlow, Axel

    2016-10-01

    Ancient DNA studies have revolutionized the study of extinct species and populations, providing insights on phylogeny, phylogeography, admixture and demographic history. However, inferences on behaviour and sociality have been far less frequent. Here, we investigate the complete mitochondrial genomes of extinct Late Pleistocene cave bears and middle Holocene brown bears that each inhabited multiple geographically proximate caves in northern Spain. In cave bears, we find that, although most caves were occupied simultaneously, each cave almost exclusively contains a unique lineage of closely related haplotypes. This remarkable pattern suggests extreme fidelity to their birth site in cave bears, best described as homing behaviour, and that cave bears formed stable maternal social groups at least for hibernation. In contrast, brown bears do not show any strong association of mitochondrial lineage and cave, suggesting that these two closely related species differed in aspects of their behaviour and sociality. This difference is likely to have contributed to cave bear extinction, which occurred at a time in which competition for caves between bears and humans was likely intense and the ability to rapidly colonize new hibernation sites would have been crucial for the survival of a species so dependent on caves for hibernation as cave bears. Our study demonstrates the potential of ancient DNA to uncover patterns of behaviour and sociality in ancient species and populations, even those that went extinct many tens of thousands of years ago. © 2016 John Wiley & Sons Ltd.

  16. High-resolution analysis of cytosine methylation in ancient DNA.

    Directory of Open Access Journals (Sweden)

    Bastien Llamas

    Full Text Available Epigenetic changes to gene expression can result in heritable phenotypic characteristics that are not encoded in the DNA itself, but rather by biochemical modifications to the DNA or associated chromatin proteins. Interposed between genes and environment, these epigenetic modifications can be influenced by environmental factors to affect phenotype for multiple generations. This raises the possibility that epigenetic states provide a substrate for natural selection, with the potential to participate in the rapid adaptation of species to changes in environment. Any direct test of this hypothesis would require the ability to measure epigenetic states over evolutionary timescales. Here we describe the first single-base resolution of cytosine methylation patterns in an ancient mammalian genome, by bisulphite allelic sequencing of loci from late Pleistocene Bison priscus remains. Retrotransposons and the differentially methylated regions of imprinted loci displayed methylation patterns identical to those derived from fresh bovine tissue, indicating that methylation patterns are preserved in the ancient DNA. Our findings establish the biochemical stability of methylated cytosines over extensive time frames, and provide the first direct evidence that cytosine methylation patterns are retained in DNA from ancient specimens. The ability to resolve cytosine methylation in ancient DNA provides a powerful means to study the role of epigenetics in evolution.

  17. Evidence of ancient DNA reveals the first European lineage in Iron Age Central China.

    Science.gov (United States)

    Xie, C Z; Li, C X; Cui, Y Q; Zhang, Q C; Fu, Y Q; Zhu, H; Zhou, H

    2007-07-07

    Various studies on ancient DNA have attempted to reconstruct population movement in Asia, with much interest focused on determining the arrival of European lineages in ancient East Asia. Here, we discuss our analysis of the mitochondrial DNA of human remains excavated from the Yu Hong tomb in Taiyuan, China, dated 1400 years ago. The burial style of this tomb is characteristic of Central Asia at that time. Our analysis shows that Yu Hong belonged to the haplogroup U5, one of the oldest western Eurasian-specific haplogroups, while his wife can be classified as haplogroup G, the type prevalent in East Asia. Our findings show that this man with European lineage arrived in Taiyuan approximately 1400 years ago, and most probably married a local woman. Haplogroup U5 was the first west Eurasian-specific lineage to be found in the central part of ancient China, and Taiyuan may be the easternmost location of the discovered remains of European lineage in ancient China.

  18. The study of human Y chromosome variation through ancient DNA.

    Science.gov (United States)

    Kivisild, Toomas

    2017-05-01

    High throughput sequencing methods have completely transformed the study of human Y chromosome variation by offering a genome-scale view on genetic variation retrieved from ancient human remains in context of a growing number of high coverage whole Y chromosome sequence data from living populations from across the world. The ancient Y chromosome sequences are providing us the first exciting glimpses into the past variation of male-specific compartment of the genome and the opportunity to evaluate models based on previously made inferences from patterns of genetic variation in living populations. Analyses of the ancient Y chromosome sequences are challenging not only because of issues generally related to ancient DNA work, such as DNA damage-induced mutations and low content of endogenous DNA in most human remains, but also because of specific properties of the Y chromosome, such as its highly repetitive nature and high homology with the X chromosome. Shotgun sequencing of uniquely mapping regions of the Y chromosomes to sufficiently high coverage is still challenging and costly in poorly preserved samples. To increase the coverage of specific target SNPs capture-based methods have been developed and used in recent years to generate Y chromosome sequence data from hundreds of prehistoric skeletal remains. Besides the prospects of testing directly as how much genetic change in a given time period has accompanied changes in material culture the sequencing of ancient Y chromosomes allows us also to better understand the rate at which mutations accumulate and get fixed over time. This review considers genome-scale evidence on ancient Y chromosome diversity that has recently started to accumulate in geographic areas favourable to DNA preservation. More specifically the review focuses on examples of regional continuity and change of the Y chromosome haplogroups in North Eurasia and in the New World.

  19. Developing a biological dosimeter based on mitochondrial DNA

    Energy Technology Data Exchange (ETDEWEB)

    Adams, S; Carlisle, S M; Unrau, P; Deugau, K V [Atomic Energy of Canada Ltd., Chalk River, ON (Canada)

    1996-12-31

    Direct measurement of deoxyribonucleic acid (DNA) damage from ionizing radiation may be advantageous in determining radiation radiation exposures and assessing their effects on atomic radiation workers. The mitochondrial DNA molecule is one potential cellular DNA target which is: fully defined and sequenced; present in many copies per cell; not vital to cellular survival; and less subject to DNA repair than nuclear DNA. A method is described to isolate and analyse normal mitochondrial DNA. We describe the developments needed to determine DNA damage in mitochondrial DNA. The target is to make a biological dosimeter. (author). 6 refs., 3 figs.

  20. Developing a biological dosimeter based on mitochondrial DNA

    International Nuclear Information System (INIS)

    Adams, S.; Carlisle, S.M.; Unrau, P.; Deugau, K.V.

    1995-01-01

    Direct measurement of deoxyribonucleic acid (DNA) damage from ionizing radiation may be advantageous in determining radiation radiation exposures and assessing their effects on atomic radiation workers. The mitochondrial DNA molecule is one potential cellular DNA target which is: fully defined and sequenced; present in many copies per cell; not vital to cellular survival; and less subject to DNA repair than nuclear DNA. A method is described to isolate and analyse normal mitochondrial DNA. We describe the developments needed to determine DNA damage in mitochondrial DNA. The target is to make a biological dosimeter. (author). 6 refs., 3 figs

  1. Characterising the potential of sheep wool for ancient DNA analyses

    DEFF Research Database (Denmark)

    Brandt, Luise Ørsted; Tranekjer, Lena D.; Mannering, Ulla

    2011-01-01

    can be PCR-amplified from wool derived from a variety of breeds, regardless of the body location or natural pigmentation. Furthermore, although DNA can be PCR-amplified from wool dyed with one of four common plant dyes (tansy, woad, madder, weld), the use of mordants such as alum or iron leads...... and content of DNA in hair shafts are known to vary, and it is possible that common treatments of wool such as dyeing may negatively impact the DNA. Using quantitative real-time polymerase chain reaction (PCR), we demonstrate that in general, short fragments of both mitochondrial and single-copy nuclear DNA...

  2. Solar radiation and mitochondrial DNA damage

    International Nuclear Information System (INIS)

    Hill, H.Z.; Locitzer, J.; Nassrin, E.; Ogbonnaya, A.; Hubbard, K.

    2003-01-01

    The 16.6 kB human mitochondrial DNA contains two homologous 13 base pair direct repeats separated by about 5 kB. During asynchronous mitochondrial DNA replication, the distant repeat sequences are thought to anneal, resulting in the looping out of a portion of the non-template strand which is subsequently deleted as a result of interaction with reactive oxygen species (ROS). A normal daughter and a deleted daughter mitochondrion result from such insults. This deletion has been termed the common deletion as it is the most frequent of the known mitochondrial DNA deletions. The common deletion is present in high frequency in several mitochondrial disorders, accumulates with age in slow turnover tissues and is increased in sun-exposed skin. Berneburg, et al. (Photochem. Photobiol. 66: 271, 1997) induced the common deletion in normal human fibroblasts after repeated exposures to UVA. In this study, the common deletion has been shown to be induced by repeated non-lethal exposures to FS20 sunlamp irradiation. Increases in the common deletion were demonstrated using nested PCR which produced a 303 bp product that was compared to a 324 bp product that required the presence of the undeleted 5 kB region. The cells were exposed to 10 repeated doses ranging from 0.5 (UVB) - 0.24 (UVA) J/sq m to 14.4 (UVB) - 5.8 J/sq m (UVA) measured using a UVX digital radiometer and UVB and UVA detectors respectively. Comparison with the earlier study by Berneberg, et al. suggests that this type of simulated solar damage is considerably more effective in fewer exposures than UVA radiation alone. The common deletion provides a cytoplasmic end-point for ROS damage produced by low dose chronic irradiations and other low level toxic exposures and should prove useful in evaluating cytoplasmic damage produced by ionizing radiation as well

  3. Natural transformation of bacteria by fragmented, damaged and ancient DNA

    DEFF Research Database (Denmark)

    Overballe-Petersen, Søren

    with fullgenome comparisons that the process has general relevance in extant bacteria. Our findings reveal that the large environmental reservoir of short and damaged DNA retains capacity for natural transformation, even after thousands of years. This describes for the first time a process by which cells can...... transfer playing an important role early in the evolution of life. The published article explains the chemical structure behind an observed degradation difference between the two purine-nucleotides guanosine and adenosine in ancient DNA. We also point at new uses for high-through-put DNA sequencing...

  4. Return of the mitochondrial DNA : Case study of mitochondrial genome evolution in the genus Fusarium

    NARCIS (Netherlands)

    Brankovics, Balázs

    2018-01-01

    Mitochondrial DNA played a prominent role in the fields of population genetics, systematics and evolutionary biology, due to its favorable characteristics, such as, uniparental inheritance, fast evolution and easy accessibility. However, the mitochondrial sequences have been mostly neglected in

  5. Ancient DNA from Nubian and Somali wild ass provides insights into donkey ancestry and domestication.

    Science.gov (United States)

    Kimura, Birgitta; Marshall, Fiona B; Chen, Shanyuan; Rosenbom, Sónia; Moehlman, Patricia D; Tuross, Noreen; Sabin, Richard C; Peters, Joris; Barich, Barbara; Yohannes, Hagos; Kebede, Fanuel; Teclai, Redae; Beja-Pereira, Albano; Mulligan, Connie J

    2011-01-07

    Genetic data from extant donkeys (Equus asinus) have revealed two distinct mitochondrial DNA haplogroups, suggestive of two separate domestication events in northeast Africa about 5000 years ago. Without distinct phylogeographic structure in domestic donkey haplogroups and with little information on the genetic makeup of the ancestral African wild ass, however, it has been difficult to identify wild ancestors and geographical origins for the domestic mitochondrial clades. Our analysis of ancient archaeological and historic museum samples provides the first genetic information on the historic Nubian wild ass (Equus africanus africanus), Somali wild ass (Equus africanus somaliensis) and ancient donkey. The results demonstrate that the Nubian wild ass was an ancestor of the first donkey haplogroup. In contrast, the Somali wild ass has considerable mitochondrial divergence from the Nubian wild ass and domestic donkeys. These findings resolve the long-standing issue of the role of the Nubian wild ass in the domestication of the donkey, but raise new questions regarding the second ancestor for the donkey. Our results illustrate the complexity of animal domestication, and have conservation implications for critically endangered Nubian and Somali wild ass.

  6. Plasmodium vivax populations revisited: mitochondrial genomes of temperate strains in Asia suggest ancient population expansion

    Directory of Open Access Journals (Sweden)

    Miao Miao

    2012-02-01

    Full Text Available Abstract Background Plasmodium vivax is the most widely distributed human malaria parasite outside of Africa, and its range extends well into the temperate zones. Previous studies provided evidence for vivax population differentiation, but temperate vivax parasites were not well represented in these analyses. Here we address this deficit by using complete mitochondrial (mt genome sequences to elucidate the broad genetic diversity and population structure of P. vivax from temperate regions in East and Southeast Asia. Results From the complete mtDNA sequences of 99 clinical samples collected in China, Myanmar and Korea, a total of 30 different haplotypes were identified from 26 polymorphic sites. Significant differentiation between different East and Southeast Asian parasite populations was observed except for the comparison between populations from Korea and southern China. Haplotype patterns and structure diversity analysis showed coexistence of two different groups in East Asia, which were genetically related to the Southeast Asian population and Myanmar population, respectively. The demographic history of P. vivax, examined using neutrality tests and mismatch distribution analyses, revealed population expansion events across the entire P. vivax range and the Myanmar population. Bayesian skyline analysis further supported the occurrence of ancient P. vivax population expansion. Conclusions This study provided further resolution of the population structure and evolution of P. vivax, especially in temperate/warm-temperate endemic areas of Asia. The results revealed divergence of the P. vivax populations in temperate regions of China and Korea from other populations. Multiple analyses confirmed ancient population expansion of this parasite. The extensive genetic diversity of the P. vivax populations is consistent with phenotypic plasticity of the parasites, which has implications for malaria control.

  7. Roles of Mitochondrial DNA Mutations in Stem Cell Ageing

    Directory of Open Access Journals (Sweden)

    Tianhong Su

    2018-03-01

    Full Text Available Mitochondrial DNA (mtDNA mutations accumulate in somatic stem cells during ageing and cause mitochondrial dysfunction. In this review, we summarize the studies that link mtDNA mutations to stem cell ageing. We discuss the age-related behaviours of the somatic mtDNA mutations in stem cell populations and how they potentially contribute to stem cell ageing by altering mitochondrial properties in humans and in mtDNA-mutator mice. We also draw attention to the diverse fates of the mtDNA mutations with different origins during ageing, with potential selective pressures on the germline inherited but not the somatic mtDNA mutations.

  8. Ancient DNA: Would the Real Neandertal Please Stand up?

    DEFF Research Database (Denmark)

    Cooper, Alan; Drummond, Alexei J.; Willerslev, Eske

    2004-01-01

    Mitochondrial DNA sequences recovered from eight Neandertal specimens cannot be detected in either early fossil Europeans or in modern populations. This indicates that, if Neandertals made any genetic contribution at all to modern humans, it must have been limited, though the extent of the contri...

  9. The efficiency of mitochondrial DNA markers in constructing genetic ...

    African Journals Online (AJOL)

    The efficiency of mitochondrial DNA markers in constructing genetic relationship among Oryx species. ... These data were used to provide the genetic kinship among different Oryx species. The complete cytochrome b gene ... Key words: Conservation, endangered species, Oryx, mitochondrial DNA (mtDNA) markers.

  10. Sequence analysis of mitochondrial DNA hypervariable region III of ...

    African Journals Online (AJOL)

    The aims of this research were to study mitochondrial DNA hypervariable region III and establish the degree of variation characteristic of a fragment. The mitochondrial DNA (mtDNA) is a small circular genome located within the mitochondria in the cytoplasm of the cell and a smaller 1.2 kb pair fragment, called the control ...

  11. Ancient and modern DNA reveal dynamics of domestication and cross-continental dispersal of the dromedary

    Science.gov (United States)

    Almathen, Faisal; Charruau, Pauline; Mohandesan, Elmira; Mwacharo, Joram M.; Orozco-terWengel, Pablo; Pitt, Daniel; Abdussamad, Abdussamad M.; Uerpmann, Margarethe; Uerpmann, Hans-Peter; De Cupere, Bea; Magee, Peter; Alnaqeeb, Majed A.; Salim, Bashir; Raziq, Abdul; Dessie, Tadelle; Abdelhadi, Omer M.; Banabazi, Mohammad H.; Al-Eknah, Marzook; Walzer, Chris; Faye, Bernard; Hofreiter, Michael; Peters, Joris; Hanotte, Olivier

    2016-01-01

    Dromedaries have been fundamental to the development of human societies in arid landscapes and for long-distance trade across hostile hot terrains for 3,000 y. Today they continue to be an important livestock resource in marginal agro-ecological zones. However, the history of dromedary domestication and the influence of ancient trading networks on their genetic structure have remained elusive. We combined ancient DNA sequences of wild and early-domesticated dromedary samples from arid regions with nuclear microsatellite and mitochondrial genotype information from 1,083 extant animals collected across the species’ range. We observe little phylogeographic signal in the modern population, indicative of extensive gene flow and virtually affecting all regions except East Africa, where dromedary populations have remained relatively isolated. In agreement with archaeological findings, we identify wild dromedaries from the southeast Arabian Peninsula among the founders of the domestic dromedary gene pool. Approximate Bayesian computations further support the “restocking from the wild” hypothesis, with an initial domestication followed by introgression from individuals from wild, now-extinct populations. Compared with other livestock, which show a long history of gene flow with their wild ancestors, we find a high initial diversity relative to the native distribution of the wild ancestor on the Arabian Peninsula and to the brief coexistence of early-domesticated and wild individuals. This study also demonstrates the potential to retrieve ancient DNA sequences from osseous remains excavated in hot and dry desert environments. PMID:27162355

  12. News from the west: ancient DNA from a French megalithic burial chamber.

    Science.gov (United States)

    Deguilloux, Marie-France; Soler, Ludovic; Pemonge, Marie-Hélène; Scarre, Chris; Joussaume, Roger; Laporte, Luc

    2011-01-01

    Recent paleogenetic studies have confirmed that the spread of the Neolithic across Europe was neither genetically nor geographically uniform. To extend existing knowledge of the mitochondrial European Neolithic gene pool, we examined six samples of human skeletal material from a French megalithic long mound (c.4200 cal BC). We retrieved HVR-I sequences from three individuals and demonstrated that in the Neolithic period the mtDNA haplogroup N1a, previously only known in central Europe, was as widely distributed as western France. Alternative scenarios are discussed in seeking to explain this result, including Mesolithic ancestry, Neolithic demic diffusion, and long-distance matrimonial exchanges. In light of the limited Neolithic ancient DNA (aDNA) data currently available, we observe that all three scenarios appear equally consistent with paleogenetic and archaeological data. In consequence, we advocate caution in interpreting aDNA in the context of the Neolithic transition in Europe. Nevertheless, our results strengthen conclusions demonstrating genetic discontinuity between modern and ancient Europeans whether through migration, demographic or selection processes, or social practices. Copyright © 2010 Wiley-Liss, Inc.

  13. Targeted transgenic overexpression of mitochondrial thymidine kinase (TK2) alters mitochondrial DNA (mtDNA) and mitochondrial polypeptide abundance: transgenic TK2, mtDNA, and antiretrovirals.

    Science.gov (United States)

    Hosseini, Seyed H; Kohler, James J; Haase, Chad P; Tioleco, Nina; Stuart, Tami; Keebaugh, Erin; Ludaway, Tomika; Russ, Rodney; Green, Elgin; Long, Robert; Wang, Liya; Eriksson, Staffan; Lewis, William

    2007-03-01

    Mitochondrial toxicity limits nucleoside reverse transcriptase inhibitors (NRTIs) for acquired immune deficiency syndrome. NRTI triphosphates, the active moieties, inhibit human immunodeficiency virus reverse transcriptase and eukaryotic mitochondrial DNA polymerase pol-gamma. NRTI phosphorylation seems to correlate with mitochondrial toxicity, but experimental evidence is lacking. Transgenic mice (TGs) with cardiac overexpression of thymidine kinase isoforms (mitochondrial TK2 and cytoplasmic TK1) were used to study NRTI mitochondrial toxicity. Echocardiography and nuclear magnetic resonance imaging defined cardiac performance and structure. TK gene copy and enzyme activity, mitochondrial (mt) DNA and polypeptide abundance, succinate dehydrogenase and cytochrome oxidase histochemistry, and electron microscopy correlated with transgenesis, mitochondrial structure, and biogenesis. Antiretroviral combinations simulated therapy. Untreated hTK1 or TK2 TGs exhibited normal left ventricle mass. In TK2 TGs, cardiac TK2 gene copy doubled, activity increased 300-fold, and mtDNA abundance doubled. Abundance of the 17-kd subunit of complex I, succinate dehydrogenase histochemical activity, and cristae density increased. NRTIs increased left ventricle mass 20% in TK2 TGs. TK activity increased 3 logs in hTK1 TGs, but no cardiac phenotype resulted. NRTIs abrogated functional effects of transgenically increased TK2 activity but had no effect on TK2 mtDNA abundance. Thus, NRTI mitochondrial phosphorylation by TK2 is integral to clinical NRTI mitochondrial toxicity.

  14. Disruption of mitochondrial DNA replication in Drosophila increases mitochondrial fast axonal transport in vivo.

    Directory of Open Access Journals (Sweden)

    Rehan M Baqri

    Full Text Available Mutations in mitochondrial DNA polymerase (pol gamma cause several progressive human diseases including Parkinson's disease, Alper's syndrome, and progressive external ophthalmoplegia. At the cellular level, disruption of pol gamma leads to depletion of mtDNA, disrupts the mitochondrial respiratory chain, and increases susceptibility to oxidative stress. Although recent studies have intensified focus on the role of mtDNA in neuronal diseases, the changes that take place in mitochondrial biogenesis and mitochondrial axonal transport when mtDNA replication is disrupted are unknown. Using high-speed confocal microscopy, electron microscopy and biochemical approaches, we report that mutations in pol gamma deplete mtDNA levels and lead to an increase in mitochondrial density in Drosophila proximal nerves and muscles, without a noticeable increase in mitochondrial fragmentation. Furthermore, there is a rise in flux of bidirectional mitochondrial axonal transport, albeit with slower kinesin-based anterograde transport. In contrast, flux of synaptic vesicle precursors was modestly decreased in pol gamma-alpha mutants. Our data indicate that disruption of mtDNA replication does not hinder mitochondrial biogenesis, increases mitochondrial axonal transport, and raises the question of whether high levels of circulating mtDNA-deficient mitochondria are beneficial or deleterious in mtDNA diseases.

  15. Ancient DNA in historical parchments - identifying a procedure for extraction and amplification of genetic material.

    Science.gov (United States)

    Lech, T

    2016-05-06

    Historical parchments in the form of documents, manuscripts, books, or letters, make up a large portion of cultural heritage collections. Their priceless historical value is associated with not only their content, but also the information hidden in the DNA deposited on them. Analyses of ancient DNA (aDNA) retrieved from parchments can be used in various investigations, including, but not limited to, studying their authentication, tracing the development of the culture, diplomacy, and technology, as well as obtaining information on the usage and domestication of animals. This article proposes and verifies a procedure for aDNA recovery from historical parchments and its appropriate preparation for further analyses. This study involved experimental selection of an aDNA extraction method with the highest efficiency and quality of extracted genetic material, from among the multi-stage phenol-chloroform extraction methods, and the modern, column-based techniques that use selective DNA-binding membranes. Moreover, current techniques to amplify entire genetic material were questioned, and the possibility of using mitochondrial DNA for species identification was analyzed. The usefulness of the proposed procedure was successfully confirmed in identification tests of historical parchments dating back to the 13-16th century AD.

  16. Establishing the validity of domestication genes using DNA from ancient chickens

    Science.gov (United States)

    Girdland Flink, Linus; Allen, Richard; Barnett, Ross; Malmström, Helena; Peters, Joris; Eriksson, Jonas; Andersson, Leif; Dobney, Keith

    2014-01-01

    Modern domestic plants and animals are subject to human-driven selection for desired phenotypic traits and behavior. Large-scale genetic studies of modern domestic populations and their wild relatives have revealed not only the genetic mechanisms underlying specific phenotypic traits, but also allowed for the identification of candidate domestication genes. Our understanding of the importance of these genes during the initial stages of the domestication process traditionally rests on the assumption that robust inferences about the past can be made on the basis of modern genetic datasets. A growing body of evidence from ancient DNA studies, however, has revealed that ancient and even historic populations often bear little resemblance to their modern counterparts. Here, we test the temporal context of selection on specific genetic loci known to differentiate modern domestic chickens from their extant wild ancestors. We extracted DNA from 80 ancient chickens excavated from 12 European archaeological sites, dated from ∼280 B.C. to the 18th century A.D. We targeted three unlinked genetic loci: the mitochondrial control region, a gene associated with yellow skin color (β-carotene dioxygenase 2), and a putative domestication gene thought to be linked to photoperiod and reproduction (thyroid-stimulating hormone receptor, TSHR). Our results reveal significant variability in both nuclear genes, suggesting that the commonality of yellow skin in Western breeds and the near fixation of TSHR in all modern chickens took place only in the past 500 y. In addition, mitochondrial variation has increased as a result of recent admixture with exotic breeds. We conclude by emphasizing the perils of inferring the past from modern genetic data alone. PMID:24753608

  17. Establishing the validity of domestication genes using DNA from ancient chickens.

    Science.gov (United States)

    Girdland Flink, Linus; Allen, Richard; Barnett, Ross; Malmström, Helena; Peters, Joris; Eriksson, Jonas; Andersson, Leif; Dobney, Keith; Larson, Greger

    2014-04-29

    Modern domestic plants and animals are subject to human-driven selection for desired phenotypic traits and behavior. Large-scale genetic studies of modern domestic populations and their wild relatives have revealed not only the genetic mechanisms underlying specific phenotypic traits, but also allowed for the identification of candidate domestication genes. Our understanding of the importance of these genes during the initial stages of the domestication process traditionally rests on the assumption that robust inferences about the past can be made on the basis of modern genetic datasets. A growing body of evidence from ancient DNA studies, however, has revealed that ancient and even historic populations often bear little resemblance to their modern counterparts. Here, we test the temporal context of selection on specific genetic loci known to differentiate modern domestic chickens from their extant wild ancestors. We extracted DNA from 80 ancient chickens excavated from 12 European archaeological sites, dated from ∼ 280 B.C. to the 18th century A.D. We targeted three unlinked genetic loci: the mitochondrial control region, a gene associated with yellow skin color (β-carotene dioxygenase 2), and a putative domestication gene thought to be linked to photoperiod and reproduction (thyroid-stimulating hormone receptor, TSHR). Our results reveal significant variability in both nuclear genes, suggesting that the commonality of yellow skin in Western breeds and the near fixation of TSHR in all modern chickens took place only in the past 500 y. In addition, mitochondrial variation has increased as a result of recent admixture with exotic breeds. We conclude by emphasizing the perils of inferring the past from modern genetic data alone.

  18. Ancient DNA (aDNA): What is it? Why is it important?- Fact Sheet

    OpenAIRE

    Alexa Walker; George Nicholas; Daryl Pullman; Alan Goodman; Bioarchaeology and Genetics Working Group

    2014-01-01

    As genetic research is increasingly applied to new areas of study, including in archaeological and heritage contexts, a range of questions arise concerning the social, ethical, legal, and political implications of ancient DNA. This fact sheet explains the nature and challenges of aDNA research, and why information from it is important and relevant to people today.  

  19. Retroviral DNA Sequences as a Means for Determining Ancient Diets.

    Directory of Open Access Journals (Sweden)

    Jessica I Rivera-Perez

    Full Text Available For ages, specialists from varying fields have studied the diets of the primeval inhabitants of our planet, detecting diet remains in archaeological specimens using a range of morphological and biochemical methods. As of recent, metagenomic ancient DNA studies have allowed for the comparison of the fecal and gut microbiomes associated to archaeological specimens from various regions of the world; however the complex dynamics represented in those microbial communities still remain unclear. Theoretically, similar to eukaryote DNA the presence of genes from key microbes or enzymes, as well as the presence of DNA from viruses specific to key organisms, may suggest the ingestion of specific diet components. In this study we demonstrate that ancient virus DNA obtained from coprolites also provides information reconstructing the host's diet, as inferred from sequences obtained from pre-Columbian coprolites. This depicts a novel and reliable approach to determine new components as well as validate the previously suggested diets of extinct cultures and animals. Furthermore, to our knowledge this represents the first description of the eukaryotic viral diversity found in paleofaeces belonging to pre-Columbian cultures.

  20. Pathogenic microbial ancient DNA: a problem or an opportunity?

    DEFF Research Database (Denmark)

    Willerslev, Eske; Cooper, Alan

    2006-01-01

    cloning. Yet these studies have used mobile insertion elements (e.g. IS 6110 in tuberculosis) or conserved loci (e.g. 16S) to detect the presence of pathogens, and very similar or identical sequences have been reported from environmental bacteria (Gilbert et al. 2004). For example, Rollo & Marota (1999......We agree with Donoghue & Spigelman (2005) that, although pathogen studies hold great potential, any discussion requires a critical assessment of the results to date. However, we did note, as did Pääbo et al. (2004), that the field of ancient pathogen DNA still lacks a series of well......-controlled and rigorous studies that address technical issues and reliability criteria. This is unfortunate, as the rapid evolutionary rate of many pathogens offers a unique means to establish the authenticity of ancient pathogen sequences-since they should clearly be ancestral to modern genetic diversity (e.g. Reid et...

  1. Complete mitochondrial genome sequence of a Middle Pleistocene cave bear reconstructed from ultrashort DNA fragments.

    Science.gov (United States)

    Dabney, Jesse; Knapp, Michael; Glocke, Isabelle; Gansauge, Marie-Theres; Weihmann, Antje; Nickel, Birgit; Valdiosera, Cristina; García, Nuria; Pääbo, Svante; Arsuaga, Juan-Luis; Meyer, Matthias

    2013-09-24

    Although an inverse relationship is expected in ancient DNA samples between the number of surviving DNA fragments and their length, ancient DNA sequencing libraries are strikingly deficient in molecules shorter than 40 bp. We find that a loss of short molecules can occur during DNA extraction and present an improved silica-based extraction protocol that enables their efficient retrieval. In combination with single-stranded DNA library preparation, this method enabled us to reconstruct the mitochondrial genome sequence from a Middle Pleistocene cave bear (Ursus deningeri) bone excavated at Sima de los Huesos in the Sierra de Atapuerca, Spain. Phylogenetic reconstructions indicate that the U. deningeri sequence forms an early diverging sister lineage to all Western European Late Pleistocene cave bears. Our results prove that authentic ancient DNA can be preserved for hundreds of thousand years outside of permafrost. Moreover, the techniques presented enable the retrieval of phylogenetically informative sequences from samples in which virtually all DNA is diminished to fragments shorter than 50 bp.

  2. High-Throughput DNA sequencing of ancient wood.

    Science.gov (United States)

    Wagner, Stefanie; Lagane, Frédéric; Seguin-Orlando, Andaine; Schubert, Mikkel; Leroy, Thibault; Guichoux, Erwan; Chancerel, Emilie; Bech-Hebelstrup, Inger; Bernard, Vincent; Billard, Cyrille; Billaud, Yves; Bolliger, Matthias; Croutsch, Christophe; Čufar, Katarina; Eynaud, Frédérique; Heussner, Karl Uwe; Köninger, Joachim; Langenegger, Fabien; Leroy, Frédéric; Lima, Christine; Martinelli, Nicoletta; Momber, Garry; Billamboz, André; Nelle, Oliver; Palomo, Antoni; Piqué, Raquel; Ramstein, Marianne; Schweichel, Roswitha; Stäuble, Harald; Tegel, Willy; Terradas, Xavier; Verdin, Florence; Plomion, Christophe; Kremer, Antoine; Orlando, Ludovic

    2018-03-01

    Reconstructing the colonization and demographic dynamics that gave rise to extant forests is essential to forecasts of forest responses to environmental changes. Classical approaches to map how population of trees changed through space and time largely rely on pollen distribution patterns, with only a limited number of studies exploiting DNA molecules preserved in wooden tree archaeological and subfossil remains. Here, we advance such analyses by applying high-throughput (HTS) DNA sequencing to wood archaeological and subfossil material for the first time, using a comprehensive sample of 167 European white oak waterlogged remains spanning a large temporal (from 550 to 9,800 years) and geographical range across Europe. The successful characterization of the endogenous DNA and exogenous microbial DNA of 140 (~83%) samples helped the identification of environmental conditions favouring long-term DNA preservation in wood remains, and started to unveil the first trends in the DNA decay process in wood material. Additionally, the maternally inherited chloroplast haplotypes of 21 samples from three periods of forest human-induced use (Neolithic, Bronze Age and Middle Ages) were found to be consistent with those of modern populations growing in the same geographic areas. Our work paves the way for further studies aiming at using ancient DNA preserved in wood to reconstruct the micro-evolutionary response of trees to climate change and human forest management. © 2018 John Wiley & Sons Ltd.

  3. Absence of ancient DNA in sub-fossil insect inclusions preserved in 'Anthropocene' Colombian copal.

    Directory of Open Access Journals (Sweden)

    David Penney

    Full Text Available Insects preserved in copal, the sub-fossilized resin precursor of amber, have potential value in molecular ecological studies of recently-extinct species and of extant species that have never been collected as living specimens. The objective of the work reported in this paper was therefore to determine if ancient DNA is present in insects preserved in copal. We prepared DNA libraries from two stingless bees (Apidae: Meliponini: Trigonisca ameliae preserved in 'Anthropocene' Colombian copal, dated to 'post-Bomb' and 10,612±62 cal yr BP, respectively, and obtained sequence reads using the GS Junior 454 System. Read numbers were low, but were significantly higher for DNA extracts prepared from crushed insects compared with extracts obtained by a non-destructive method. The younger specimen yielded sequence reads up to 535 nucleotides in length, but searches of these sequences against the nucleotide database revealed very few significant matches. None of these hits was to stingless bees though one read of 97 nucleotides aligned with two non-contiguous segments of the mitochondrial cytochrome oxidase subunit I gene of the East Asia bumblebee Bombus hypocrita. The most significant hit was for 452 nucleotides of a 470-nucleotide read that aligned with part of the genome of the root-nodulating bacterium Bradyrhizobium japonicum. The other significant hits were to proteobacteria and an actinomycete. Searches directed specifically at Apidae nucleotide sequences only gave short and insignificant alignments. All of the reads from the older specimen appeared to be artefacts. We were therefore unable to obtain any convincing evidence for the preservation of ancient DNA in either of the two copal inclusions that we studied, and conclude that DNA is not preserved in this type of material. Our results raise further doubts about claims of DNA extraction from fossil insects in amber, many millions of years older than copal.

  4. Sequence analysis of mitochondrial DNA hypervariable region III of ...

    African Journals Online (AJOL)

    Aghomotsegin

    2015-07-01

    Jul 1, 2015 ... population genetics research, studies based on mitochondrial DNA (mtDNA) and Y-chromosome DNA are an excellent way of illustrating population structure .... avoid landing investigators into serious situations of medical genetic privacy and ethnics, especially for. mtDNA coding area whose mutation often ...

  5. Application and comparison of large-scale solution-based DNA capture-enrichment methods on ancient DNA

    DEFF Research Database (Denmark)

    Avila Arcos, Maria del Carmen; Cappellini, Enrico; Romero-Navarro, J. Alberto

    2011-01-01

    The development of second-generation sequencing technologies has greatly benefitted the field of ancient DNA (aDNA). Its application can be further exploited by the use of targeted capture-enrichment methods to overcome restrictions posed by low endogenous and contaminating DNA in ancient samples...

  6. Mitochondrial DNA evolution in the genus Equus.

    Science.gov (United States)

    George, M; Ryder, O A

    1986-11-01

    Employing mitochondrial DNA (mtDNA) restriction-endonuclease maps as the basis of comparison, we have investigated the evolutionary affinities of the seven species generally recognized as the genus Equus. Individual species' cleavage maps contained an average of 60 cleavage sites for 16 enzymes, of which 29 were invariant for all species. Based on an average divergence rate of 2%/Myr, the variation between species supports a divergence of extant lineages from a common ancestor approximately 3.9 Myr before the present. Comparisons of cleavage maps between Equus przewalskii (Mongolian wild horse) and E. caballus (domestic horse) yielded estimates of nucleotide sequence divergence ranging from 0.27% to 0.41%. This range was due to intraspecific variation, which was noted only for E. caballus. For pairwise comparisons within this family, estimates of sequence divergence ranged from 0% (E. hemionus onager vs. E. h. kulan) to 7.8% (E. przewalskii vs. E. h. onager). Trees constructed according to the parsimony principle, on the basis of 31 phylogenetically informative restriction sites, indicate that the three extant zebra species represent a monophyletic group with E. grevyi and E. burchelli antiquorum diverging most recently. The phylogenetic relationships of E. africanus and E. hemionus remain enigmatic on the basis of the mtDNA analysis, although a recent divergence is unsupported.

  7. Application of Ancient DNA Methods to the Study of the Transatlantic Slave Trade

    DEFF Research Database (Denmark)

    Sandoval Velasco, Marcela

    As one of a limited number of biomolecules recording evolutionary events, DNA provides an unparalleled means of investigating genetic processes. Over three decades, ancient DNA research has matured in many ways, growing alongside technological and methodological advancements. However, due to DNA...... means of investigating genetic processes. Over three decades, ancient DNA research has matured in many ways, growing alongside technological and methodological advancements. However, due to DNA preservation, degradation and contamination, ancient DNA research presents significant limitations...... preservation, degradation and contamination, ancient DNA research presents significant limitations and challenges. Until recently, it was thought that DNA did not survive more than few hundred thousand years, and that it was impossible to retrieve whole genome data from ancient samples preserved under...

  8. Ancient DNA and the rewriting of human history: be sparing with Occam's razor.

    Science.gov (United States)

    Haber, Marc; Mezzavilla, Massimo; Xue, Yali; Tyler-Smith, Chris

    2016-01-11

    Ancient DNA research is revealing a human history far more complex than that inferred from parsimonious models based on modern DNA. Here, we review some of the key events in the peopling of the world in the light of the findings of work on ancient DNA.

  9. Mitochondrial DNA from El Mirador cave (Atapuerca, Spain reveals the heterogeneity of Chalcolithic populations.

    Directory of Open Access Journals (Sweden)

    Daniel Gómez-Sánchez

    Full Text Available Previous mitochondrial DNA analyses on ancient European remains have suggested that the current distribution of haplogroup H was modeled by the expansion of the Bell Beaker culture (ca 4,500-4,050 years BP out of Iberia during the Chalcolithic period. However, little is known on the genetic composition of contemporaneous Iberian populations that do not carry the archaeological tool kit defining this culture. Here we have retrieved mitochondrial DNA (mtDNA sequences from 19 individuals from a Chalcolithic sample from El Mirador cave in Spain, dated to 4,760-4,200 years BP and we have analyzed the haplogroup composition in the context of modern and ancient populations. Regarding extant African, Asian and European populations, El Mirador shows affinities with Near Eastern groups. In different analyses with other ancient samples, El Mirador clusters with Middle and Late Neolithic populations from Germany, belonging to the Rössen, the Salzmünde and the Baalberge archaeological cultures but not with contemporaneous Bell Beakers. Our analyses support the existence of a common genetic signal between Western and Central Europe during the Middle and Late Neolithic and points to a heterogeneous genetic landscape among Chalcolithic groups.

  10. Human mitochondrial DNA (mtDNA) types in Malaysia

    International Nuclear Information System (INIS)

    Lian, L.H.; Koh, C.L.; Lim, M.E.

    2000-01-01

    Each human cell contains hundreds of mitochondria and thousands of double-stranded circular mtDNA. The delineation of human mtDNA variation and genetics over the past decade has provided unique and often startling insights into human evolution, degenerative diseases, and aging. Each mtDNA of 16,569 base pairs, encodes 13 polypeptides essential to the enzymes of the mitochondrial energy generating pathway, plus the necessary tRNAs and rRNAs. The highly polymorphic noncoding D-(displacement) loop region, also called the control region, is approximately 1.2 kb long. It contains two well-characterized hypervariable (HV-) regions, HV1 and HV2. MtDNA identification is usually based on these sequence differences. According to the TWTGDAM (Technical Working Group for DNA Analysis Methods), the minimum requirement for a mtDNA database for HV1 is from positions 16024 to 16365 and for HV2, from positions 00073 to 00340. The targeted Malaysian population subgroups for this study were mainly the Malays, Chinese, Indians, and indigenous Ibans, Bidayuhs, Kadazan-Dusuns, and Bajaus. Research methodologies undertaken included DNA extraction of samples from unrelated individuals, amplification of the specific regions via the polymerase chain reaction (PCR), and preparation of template DNA for sequencing by using an automated DNA sequencer. Sufficient nucleotide sequence data were generated from the mtDNA analysis. When the sequences were analyzed, sequence variations were found to be caused by nucleotide substitutions, insertions, and deletions. Of the three causes of the sequence variations, nucleotide substitutions (86.1%) accounted for the vast majority of polymorphism. It is noted that transitions (83.5%) were predominant when compared to the significantly lower frequencies of transversions (2.6%). Insertions (0.9%) and deletions (13.0%) were rather rare and found only in HV2. The data generated will also form the basis of a Malaysian DNA sequence database of mtDNA D

  11. Ancient DNA Reveals Late Pleistocene Existence of Ostriches in Indian Sub-Continent.

    Directory of Open Access Journals (Sweden)

    Sonal Jain

    Full Text Available Ancient DNA (aDNA analysis of extinct ratite species is of considerable interest as it provides important insights into their origin, evolution, paleogeographical distribution and vicariant speciation in congruence with continental drift theory. In this study, DNA hotspots were detected in fossilized eggshell fragments of ratites (dated ≥25000 years B.P. by radiocarbon dating using confocal laser scanning microscopy (CLSM. DNA was isolated from five eggshell fragments and a 43 base pair (bp sequence of a 16S rRNA mitochondrial-conserved region was successfully amplified and sequenced from one of the samples. Phylogenetic analysis of the DNA sequence revealed a 92% identity of the fossil eggshells to Struthio camelus and their position basal to other palaeognaths, consistent with the vicariant speciation model. Our study provides the first molecular evidence for the presence of ostriches in India, complementing the continental drift theory of biogeographical movement of ostriches in India, and opening up a new window into the evolutionary history of ratites.

  12. Actin and myosin contribute to mammalian mitochondrial DNA maintenance

    Science.gov (United States)

    Reyes, A.; He, J.; Mao, C. C.; Bailey, L. J.; Di Re, M.; Sembongi, H.; Kazak, L.; Dzionek, K.; Holmes, J. B.; Cluett, T. J.; Harbour, M. E.; Fearnley, I. M.; Crouch, R. J.; Conti, M. A.; Adelstein, R. S.; Walker, J. E.; Holt, I. J.

    2011-01-01

    Mitochondrial DNA maintenance and segregation are dependent on the actin cytoskeleton in budding yeast. We found two cytoskeletal proteins among six proteins tightly associated with rat liver mitochondrial DNA: non-muscle myosin heavy chain IIA and β-actin. In human cells, transient gene silencing of MYH9 (encoding non-muscle myosin heavy chain IIA), or the closely related MYH10 gene (encoding non-muscle myosin heavy chain IIB), altered the topology and increased the copy number of mitochondrial DNA; and the latter effect was enhanced when both genes were targeted simultaneously. In contrast, genetic ablation of non-muscle myosin IIB was associated with a 60% decrease in mitochondrial DNA copy number in mouse embryonic fibroblasts, compared to control cells. Gene silencing of β-actin also affected mitochondrial DNA copy number and organization. Protease-protection experiments and iodixanol gradient analysis suggest some β-actin and non-muscle myosin heavy chain IIA reside within human mitochondria and confirm that they are associated with mitochondrial DNA. Collectively, these results strongly implicate the actomyosin cytoskeleton in mammalian mitochondrial DNA maintenance. PMID:21398640

  13. Conservation archaeogenomics: ancient DNA and biodiversity in the Anthropocene.

    Science.gov (United States)

    Hofman, Courtney A; Rick, Torben C; Fleischer, Robert C; Maldonado, Jesús E

    2015-09-01

    There is growing consensus that we have entered the Anthropocene, a geologic epoch characterized by human domination of the ecosystems of the Earth. With the future uncertain, we are faced with understanding how global biodiversity will respond to anthropogenic perturbations. The archaeological record provides perspective on human-environment relations through time and across space. Ancient DNA (aDNA) analyses of plant and animal remains from archaeological sites are particularly useful for understanding past human-environment interactions, which can help guide conservation decisions during the environmental changes of the Anthropocene. Here, we define the emerging field of conservation archaeogenomics, which integrates archaeological and genomic data to generate baselines or benchmarks for scientists, managers, and policy-makers by evaluating climatic and human impacts on past, present, and future biodiversity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Proteomic Dissection of the Mitochondrial DNA Metabolism Apparatus in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    SAlly A. Mackenzie

    2004-01-06

    This study involves the investigation of nuclear genetic components that regulate mitochondrial genome behavior in higher plants. The approach utilizes the advanced plant model system of Arabidopsis thaliana to identify and functionally characterize multiple components of the mitochondrial DNA replication, recombination and mismatch repair system and their interaction partners. The rationale for the research stems from the central importance of mitochondria to overall cellular metabolism and the essential nature of the mitochondrial genome to mitochondrial function. Relatively little is understood about mitochondrial DNA maintenance and transmission in higher eukaryotes, and the higher plant mitochondrial genome displays unique properties and behavior. This investigation has revealed at least three important properties of plant mitochondrial DNA metabolism components. (1) Many are dual targeted to mitochondrial and chloroplasts by novel mechanisms, suggesting that the mitochondria a nd chloroplast share their genome maintenance apparatus. (2)The MSH1 gene, originating as a component of mismatch repair, has evolved uniquely in plants to participate in differential replication of the mitochondrial genome. (3) This mitochondrial differential replication process, termed substoichiometric shifting and also involving a RecA-related gene, appears to represent an adaptive mechanism to expand plant reproductive capacity and is likely present throughout the plant kingdom.

  15. Integrating archaeology and ancient DNA analysis to address invasive species colonization in the Gulf of Alaska.

    Science.gov (United States)

    West, Catherine; Hofman, Courtney A; Ebbert, Steve; Martin, John; Shirazi, Sabrina; Dunning, Samantha; Maldonado, Jesus E

    2017-10-01

    The intentional and unintentional movement of plants and animals by humans has transformed ecosystems and landscapes globally. Assessing when and how a species was introduced are central to managing these transformed landscapes, particularly in island environments. In the Gulf of Alaska, there is considerable interest in the history of mammal introductions and rehabilitating Gulf of Alaska island environments by eradicating mammals classified as invasive species. The Arctic ground squirrel (Urocitellus parryii) is of concern because it affects vegetation and seabirds on Gulf of Alaska islands. This animal is assumed to have been introduced by historic settlers; however, ground squirrel remains in the prehistoric archaeological record of Chirikof Island, Alaska, challenge this timeline and suggest they colonized the islands long ago. We used 3 lines of evidence to address this problem: direct radiocarbon dating of archaeological squirrel remains; evidence of prehistoric human use of squirrels; and ancient DNA analysis of dated squirrel remains. Chirikof squirrels dated to at least 2000 years ago, and cut marks on squirrel bones suggested prehistoric use by people. Ancient squirrels also shared a mitochondrial haplotype with modern Chirikof squirrels. These results suggest that squirrels have been on Chirikof longer than previously assumed and that the current population of squirrels is closely related to the ancient population. Thus, it appears ground squirrels are not a recent, human-mediated introduction and may have colonized the island via a natural dispersal event or an ancient human translocation. © 2016 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

  16. RECQL4 localizes to mitochondria and preserves mitochondrial DNA integrity

    DEFF Research Database (Denmark)

    Croteau, Deborah L; Rossi, Marie L; Canugovi, Chandrika

    2012-01-01

    in premature aging. There is no information about whether any of the RecQ helicases play roles in mitochondrial biogenesis, which is strongly implicated in the aging process. Here, we used microscopy to visualize RECQL4 in mitochondria. Fractionation of human and mouse cells also showed that RECQL4 was present...... in mitochondria. Q-PCR amplification of mitochondrial DNA demonstrated that mtDNA damage accumulated in RECQL4-deficient cells. Microarray analysis suggested that mitochondrial bioenergetic pathways might be affected in RTS. Measurements of mitochondrial bioenergetics showed a reduction in the mitochondrial......Q helicase to be found in both human and mouse mitochondria, and the loss of RECQL4 alters mitochondrial integrity....

  17. Mitochondrial DNA structure in the Arabian Peninsula

    Directory of Open Access Journals (Sweden)

    Cabrera Vicente M

    2008-02-01

    Full Text Available Abstract Background Two potential migratory routes followed by modern humans to colonize Eurasia from Africa have been proposed. These are the two natural passageways that connect both continents: the northern route through the Sinai Peninsula and the southern route across the Bab al Mandab strait. Recent archaeological and genetic evidence have favored a unique southern coastal route. Under this scenario, the study of the population genetic structure of the Arabian Peninsula, the first step out of Africa, to search for primary genetic links between Africa and Eurasia, is crucial. The haploid and maternally inherited mitochondrial DNA (mtDNA molecule has been the most used genetic marker to identify and to relate lineages with clear geographic origins, as the African Ls and the Eurasian M and N that have a common root with the Africans L3. Results To assess the role of the Arabian Peninsula in the southern route, we genetically analyzed 553 Saudi Arabs using partial (546 and complete mtDNA (7 sequencing, and compared the lineages obtained with those present in Africa, the Near East, central, east and southeast Asia and Australasia. The results showed that the Arabian Peninsula has received substantial gene flow from Africa (20%, detected by the presence of L, M1 and U6 lineages; that an 18% of the Arabian Peninsula lineages have a clear eastern provenance, mainly represented by U lineages; but also by Indian M lineages and rare M links with Central Asia, Indonesia and even Australia. However, the bulk (62% of the Arabian lineages has a Northern source. Conclusion Although there is evidence of Neolithic and more recent expansions in the Arabian Peninsula, mainly detected by (preHV1 and J1b lineages, the lack of primitive autochthonous M and N sequences, suggests that this area has been more a receptor of human migrations, including historic ones, from Africa, India, Indonesia and even Australia, than a demographic expansion center along the

  18. Mitochondrial DNA depletion by ethidium bromide decreases neuronal mitochondrial creatine kinase: Implications for striatal energy metabolism.

    Science.gov (United States)

    Warren, Emily Booth; Aicher, Aidan Edward; Fessel, Joshua Patrick; Konradi, Christine

    2017-01-01

    Mitochondrial DNA (mtDNA), the discrete genome which encodes subunits of the mitochondrial respiratory chain, is present at highly variable copy numbers across cell types. Though severe mtDNA depletion dramatically reduces mitochondrial function, the impact of tissue-specific mtDNA reduction remains debated. Previously, our lab identified reduced mtDNA quantity in the putamen of Parkinson's Disease (PD) patients who had developed L-DOPA Induced Dyskinesia (LID), compared to PD patients who had not developed LID and healthy subjects. Here, we present the consequences of mtDNA depletion by ethidium bromide (EtBr) treatment on the bioenergetic function of primary cultured neurons, astrocytes and neuron-enriched cocultures from rat striatum. We report that EtBr inhibition of mtDNA replication and transcription consistently reduces mitochondrial oxygen consumption, and that neurons are significantly more sensitive to EtBr than astrocytes. EtBr also increases glycolytic activity in astrocytes, whereas in neurons it reduces the expression of mitochondrial creatine kinase mRNA and levels of phosphocreatine. Further, we show that mitochondrial creatine kinase mRNA is similarly downregulated in dyskinetic PD patients, compared to both non-dyskinetic PD patients and healthy subjects. Our data support a hypothesis that reduced striatal mtDNA contributes to energetic dysregulation in the dyskinetic striatum by destabilizing the energy buffering system of the phosphocreatine/creatine shuttle.

  19. Mitochondrial DNA depletion by ethidium bromide decreases neuronal mitochondrial creatine kinase: Implications for striatal energy metabolism.

    Directory of Open Access Journals (Sweden)

    Emily Booth Warren

    Full Text Available Mitochondrial DNA (mtDNA, the discrete genome which encodes subunits of the mitochondrial respiratory chain, is present at highly variable copy numbers across cell types. Though severe mtDNA depletion dramatically reduces mitochondrial function, the impact of tissue-specific mtDNA reduction remains debated. Previously, our lab identified reduced mtDNA quantity in the putamen of Parkinson's Disease (PD patients who had developed L-DOPA Induced Dyskinesia (LID, compared to PD patients who had not developed LID and healthy subjects. Here, we present the consequences of mtDNA depletion by ethidium bromide (EtBr treatment on the bioenergetic function of primary cultured neurons, astrocytes and neuron-enriched cocultures from rat striatum. We report that EtBr inhibition of mtDNA replication and transcription consistently reduces mitochondrial oxygen consumption, and that neurons are significantly more sensitive to EtBr than astrocytes. EtBr also increases glycolytic activity in astrocytes, whereas in neurons it reduces the expression of mitochondrial creatine kinase mRNA and levels of phosphocreatine. Further, we show that mitochondrial creatine kinase mRNA is similarly downregulated in dyskinetic PD patients, compared to both non-dyskinetic PD patients and healthy subjects. Our data support a hypothesis that reduced striatal mtDNA contributes to energetic dysregulation in the dyskinetic striatum by destabilizing the energy buffering system of the phosphocreatine/creatine shuttle.

  20. Mitochondrial DNA levels in Huntington disease leukocytes and dermal fibroblasts.

    Science.gov (United States)

    Jędrak, Paulina; Krygier, Magdalena; Tońska, Katarzyna; Drozd, Małgorzata; Kaliszewska, Magdalena; Bartnik, Ewa; Sołtan, Witold; Sitek, Emilia J; Stanisławska-Sachadyn, Anna; Limon, Janusz; Sławek, Jarosław; Węgrzyn, Grzegorz; Barańska, Sylwia

    2017-08-01

    Huntington disease (HD) is an inherited neurodegenerative disorder caused by mutations in the huntingtin gene. Involvement of mitochondrial dysfunctions in, and especially influence of the level of mitochondrial DNA (mtDNA) on, development of this disease is unclear. Here, samples of blood from 84 HD patients and 79 controls, and dermal fibroblasts from 10 HD patients and 9 controls were analysed for mtDNA levels. Although the type of mitochondrial haplogroup had no influence on the mtDNA level, and there was no correlation between mtDNA level in leukocytes in HD patients and various parameters of HD severity, some considerable differences between HD patients and controls were identified. The average mtDNA/nDNA relative copy number was significantly higher in leukocytes, but lower in fibroblasts, of symptomatic HD patients relative to the control group. Moreover, HD women displayed higher mtDNA levels in leukocytes than HD men. Because this is the largest population analysed to date, these results might contribute to explanation of discrepancies between previously published studies concerning levels of mtDNA in cells of HD patients. We suggest that the size of the investigated population and type of cells from which DNA is isolated could significantly affect results of mtDNA copy number estimation in HD. Hence, these parameters should be taken into consideration in studies on mtDNA in HD, and perhaps also in other diseases where mitochondrial dysfunction occurs.

  1. Mitochondrial DNA Mutations in Epithelial Ovarian Tumor Progression

    Science.gov (United States)

    2007-12-01

    Panici PL, Fazio VM: Mutations of D310 mitochondrial mononu- cleotide repeat in primary tumors and cytological speci- mens . Cancer Lett 2003, 190:73...BR: Detection of LOH and mitochondrial DNA alter- ations in ductal lavage and nipple aspirate fluids from high- risk patients. Breast Cancer Res

  2. Fluorescent in situ hybridization of mitochondrial DNA and RNA

    Czech Academy of Sciences Publication Activity Database

    Alán, Lukáš; Zelenka, Jaroslav; Ježek, Jan; Dlasková, Andrea; Ježek, Petr

    2010-01-01

    Roč. 57, č. 4 (2010), s. 403-408 ISSN 0001-527X R&D Projects: GA ČR GAP302/10/0346; GA ČR GPP304/10/P204; GA AV ČR KJB500110902 Institutional research plan: CEZ:AV0Z50110509 Keywords : mitochondrial DNA and RNA * nucleoids of mitochondrial DNA * molecular beacon fluorescent hybridization probes Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.234, year: 2010

  3. Mitochondrial introgression via ancient hybridization, and systematics of the Australian endemic pygopodid gecko genus Delma.

    Science.gov (United States)

    Brennan, Ian G; Bauer, Aaron M; Jackman, Todd R

    2016-01-01

    Of the more than 1500 species of geckos found across six continents, few remain as unfamiliar as the pygopodids - Family Pygopodidae (Gray, 1845). These gekkotans are limited to Australia (44 species) and New Guinea (2 species), but have diverged extensively into the most ecologically diverse limbless radiation save Serpentes. Current phylogenetic understanding of the family has relied almost exclusively on two works, which have produced and synthesized an immense amount of morphological, geographical, and molecular data. However, current interspecific relationships within the largest genus Delma Gray 1831 are based chiefly upon data from two mitochondrial loci (16s, ND2). Here, we reevaluate the interspecific relationships within the genus Delma using two mitochondrial and four nuclear loci (RAG1, MXRA5, MOS, DYNLL1), and identify points of strong conflict between nuclear and mitochondrial genomic data. We address mito-nuclear discordance, and remedy this conflict by recognizing several points of mitochondrial introgression as the result of ancient hybridization events. Owing to the legacy value and intraspecific informativeness, we suggest the continued use of ND2 as a phylogenetic marker. Results identify strong support for species groups, but relationships among these clades, and the placement of several enigmatic taxa remain uncertain. We suggest a more careful review of Delma australis and the 'northwest Australia' clade. Accurately assessing and addressing species richness and relationships within this endemic Australian Gekkotan genus is relevant for understanding patterns of squamate speciation across the region. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Pre-Columbian population dynamics in coastal southern Peru: A diachronic investigation of mtDNA patterns in the Palpa region by ancient DNA analysis.

    Science.gov (United States)

    Fehren-Schmitz, Lars; Reindel, Markus; Cagigao, Elsa Tomasto; Hummel, Susanne; Herrmann, Bernd

    2010-02-01

    Alternative models have been proposed to explain the formation and decline of the south Peruvian Nasca culture, ranging from migration or invasion to autochthonous development and ecological crisis. To reveal to what extent population dynamic processes accounted for cultural development in the Nasca mainland, or were influenced by them, we analyzed ancient mitochondrial DNA of 218 individuals, originating from chronologically successive archaeological sites in the Palpa region, the Paracas Peninsula, and the Andean highlands in southern Peru. The sampling strategy allowed a diachronic analysis in a time frame from approximately 800 BC to 800 AD. Mitochondrial coding region polymorphisms were successfully analyzed and replicated for 130 individuals and control region sequences (np 16021-16408) for 104 individuals to determine Native American mitochondrial DNA haplogroups and haplotypes. The results were compared with ancient and contemporary Peruvian populations to reveal genetic relations of the archaeological samples. Frequency data and statistics show clear proximity of the Nasca populations to the populations of the preceding Paracas culture from Palpa and the Peninsula, and suggest, along with archaeological data, that the Nasca culture developed autochthonously in the Rio Grande drainage. Furthermore, the influence of changes in socioeconomic complexity in the Palpa area on the genetic diversity of the local population could be observed. In all, a strong genetic affinity between pre-Columbian coastal populations from southern Peru could be determined, together with a significant differentiation from ancient highland and all present-day Peruvian reference populations, best shown in the differential distribution of mitochondrial haplogroups. 2009 Wiley-Liss, Inc.

  5. Ancient DNA from latrines in Northern Europe and the Middle East (500 BC–1700 AD) reveals past parasites and diet

    DEFF Research Database (Denmark)

    Søe, Martin Jensen; Nejsum, Peter; Seersholm, Frederik Valeur

    2018-01-01

    , vertebrate and plant DNA proved highly informative in the study of ancient health, human-animal interactions as well as animal and plant dietary components. Most prominent were finding of soil-borne parasites transmitted directly between humans, but also meat-borne parasites that require consumption of raw...... or undercooked fish and pork. The detection of parasites for which sheep, horse, dog, pig, and rodents serves as definitive hosts are clear markers of domestic and synanthropic animals living in closer proximity of the respective sites. Finally, the reconstruction of full mitochondrial parasite genomes from...

  6. Oxidative DNA damage causes mitochondrial genomic instability in Saccharomyces cerevisiae.

    Science.gov (United States)

    Doudican, Nicole A; Song, Binwei; Shadel, Gerald S; Doetsch, Paul W

    2005-06-01

    Mitochondria contain their own genome, the integrity of which is required for normal cellular energy metabolism. Reactive oxygen species (ROS) produced by normal mitochondrial respiration can damage cellular macromolecules, including mitochondrial DNA (mtDNA), and have been implicated in degenerative diseases, cancer, and aging. We developed strategies to elevate mitochondrial oxidative stress by exposure to antimycin and H(2)O(2) or utilizing mutants lacking mitochondrial superoxide dismutase (sod2Delta). Experiments were conducted with strains compromised in mitochondrial base excision repair (ntg1Delta) and oxidative damage resistance (pif1Delta) in order to delineate the relationship between these pathways. We observed enhanced ROS production, resulting in a direct increase in oxidative mtDNA damage and mutagenesis. Repair-deficient mutants exposed to oxidative stress conditions exhibited profound genomic instability. Elimination of Ntg1p and Pif1p resulted in a synergistic corruption of respiratory competency upon exposure to antimycin and H(2)O(2). Mitochondrial genomic integrity was substantially compromised in ntg1Delta pif1Delta sod2Delta strains, since these cells exhibit a total loss of mtDNA. A stable respiration-defective strain, possessing a normal complement of mtDNA damage resistance pathways, exhibited a complete loss of mtDNA upon exposure to antimycin and H(2)O(2). This loss was preventable by Sod2p overexpression. These results provide direct evidence that oxidative mtDNA damage can be a major contributor to mitochondrial genomic instability and demonstrate cooperation of Ntg1p and Pif1p to resist the introduction of lesions into the mitochondrial genome.

  7. Genetics Home Reference: MPV17-related hepatocerebral mitochondrial DNA depletion syndrome

    Science.gov (United States)

    ... DNA depletion syndrome MPV17-related hepatocerebral mitochondrial DNA depletion syndrome Printable PDF Open All Close All Enable ... collapse boxes. Description MPV17 -related hepatocerebral mitochondrial DNA depletion syndrome is an inherited disorder that can cause ...

  8. Setting the stage - building and working in an ancient DNA laboratory.

    Science.gov (United States)

    Knapp, Michael; Clarke, Andrew C; Horsburgh, K Ann; Matisoo-Smith, Elizabeth A

    2012-01-20

    With the introduction of next generation high throughput sequencing in 2005 and the resulting revolution in genetics, ancient DNA research has rapidly developed from an interesting but marginal field within evolutionary biology into one that can contribute significantly to our understanding of evolution in general and the development of our own species in particular. While the amount of sequence data available from ancient human, other animal and plant remains has increased dramatically over the past five years, some key limitations of ancient DNA research remain. Most notably, reduction of contamination and the authentication of results are of utmost importance. A number of studies have addressed different aspects of sampling, DNA extraction and DNA manipulation in order to establish protocols that most efficiently generate reproducible and authentic results. As increasing numbers of researchers from different backgrounds become interested in using ancient DNA technology to address key questions, the need for practical guidelines on how to construct and use an ancient DNA facility arises. The aim of this article is therefore to provide practical tips for building a state-of-the-art ancient DNA facility. It is intended to help researchers new to the field of ancient DNA research generally, and those considering the application of next generation sequencing, in their planning process. Copyright © 2011 Elsevier GmbH. All rights reserved.

  9. [Real-time quantification to analyze historical Colombian samples detecting a short fragment of hypervariable region II of mitochondrial DNA].

    Science.gov (United States)

    Pérez, Luz Adriana; Rodríguez, Freddy; Langebaek, Carl Henrik; Groot, Helena

    2016-09-01

    Unlike other molecular biology studies, the analysis of ancient DNA (aDNA) requires special infrastructure and methodological conditions to guarantee the quality of the results. One of the main authenticity criteria is DNA quantification, where quantitative real-time PCR is often used given its sensitivity and specificity. Nevertheless, the implementation of these conditions and methodologies to fulfill authenticity criteria imply higher costs. Objective: To develop a simple and less costly method for mitochondrial DNA quantification suitable for highly degraded samples. Materials and methods: The proposed method is based on the use of mini-primers for the specific amplification of short fragments of mitochondrial DNA. The subsequent purification of these amplified fragments allows a standard curve to be constructed with concentrations in accordance to the state of degradation of the samples. Results: The proposed method successfully detected DNA from ancient samples including bone remains and mummified tissue. DNA inhibitory substances were also detected. Conclusion: The proposed method represents a simpler and cost-effective way to detect low amounts of aDNA, and a tool to differentiate DNA-free samples from samples with inhibitory substances.

  10. Compound mitochondrial DNA mutations in a neurological patient ...

    Indian Academy of Sciences (India)

    Compound mitochondrial DNA mutations in a neurological patient with ataxia, myoclonus and deafness. Ji Hoon Park, Bo Ram Yoon, Hye Jin Kim, Phil Hyu Lee, Byung-Ok Choi and Ki Wha Chung. J. Genet. 93, 173–177. Table 1. Variations from the whole mtDNA sequence in the AMDF patient. Mutation. Report. Locus/ ...

  11. Human evolution in Siberia: from frozen bodies to ancient DNA

    Directory of Open Access Journals (Sweden)

    Bouakaze Caroline

    2010-01-01

    Full Text Available Abstract Background The Yakuts contrast strikingly with other populations from Siberia due to their cattle- and horse-breeding economy as well as their Turkic language. On the basis of ethnological and linguistic criteria as well as population genetic studies, it has been assumed that they originated from South Siberian populations. However, many questions regarding the origins of this intriguing population still need to be clarified (e.g. the precise origin of paternal lineages and the admixture rate with indigenous populations. This study attempts to better understand the origins of the Yakuts by performing genetic analyses on 58 mummified frozen bodies dated from the 15th to the 19th century, excavated from Yakutia (Eastern Siberia. Results High quality data were obtained for the autosomal STRs, Y-chromosomal STRs and SNPs and mtDNA due to exceptional sample preservation. A comparison with the same markers on seven museum specimens excavated 3 to 15 years ago showed significant differences in DNA quantity and quality. Direct access to ancient genetic data from these molecular markers combined with the archaeological evidence, demographical studies and comparisons with 166 contemporary individuals from the same location as the frozen bodies helped us to clarify the microevolution of this intriguing population. Conclusion We were able to trace the origins of the male lineages to a small group of horse-riders from the Cis-Baïkal area. Furthermore, mtDNA data showed that intermarriages between the first settlers with Evenks women led to the establishment of genetic characteristics during the 15th century that are still observed today.

  12. Mitochondrial DNA triplication and punctual mutations in patients with mitochondrial neuromuscular disorders

    Energy Technology Data Exchange (ETDEWEB)

    Mkaouar-Rebai, Emna, E-mail: emna.mkaouar@gmail.com [Département des Sciences de la Vie, Faculté des Sciences de Sfax, Université de Sfax (Tunisia); Felhi, Rahma; Tabebi, Mouna [Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax, Université de Sfax (Tunisia); Alila-Fersi, Olfa; Chamkha, Imen [Département des Sciences de la Vie, Faculté des Sciences de Sfax, Université de Sfax (Tunisia); Maalej, Marwa; Ammar, Marwa [Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax, Université de Sfax (Tunisia); Kammoun, Fatma [Service de pédiatrie, C.H.U. Hedi Chaker de Sfax (Tunisia); Keskes, Leila [Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax, Université de Sfax (Tunisia); Hachicha, Mongia [Service de pédiatrie, C.H.U. Hedi Chaker de Sfax (Tunisia); Fakhfakh, Faiza, E-mail: faiza.fakhfakh02@gmail.com [Département des Sciences de la Vie, Faculté des Sciences de Sfax, Université de Sfax (Tunisia)

    2016-04-29

    Mitochondrial diseases are a heterogeneous group of disorders caused by the impairment of the mitochondrial oxidative phosphorylation system which have been associated with various mutations of the mitochondrial DNA (mtDNA) and nuclear gene mutations. The clinical phenotypes are very diverse and the spectrum is still expanding. As brain and muscle are highly dependent on OXPHOS, consequently, neurological disorders and myopathy are common features of mtDNA mutations. Mutations in mtDNA can be classified into three categories: large-scale rearrangements, point mutations in tRNA or rRNA genes and point mutations in protein coding genes. In the present report, we screened mitochondrial genes of complex I, III, IV and V in 2 patients with mitochondrial neuromuscular disorders. The results showed the presence the pathogenic heteroplasmic m.9157G>A variation (A211T) in the MT-ATP6 gene in the first patient. We also reported the first case of triplication of 9 bp in the mitochondrial NC7 region in Africa and Tunisia, in association with the novel m.14924T>C in the MT-CYB gene in the second patient with mitochondrial neuromuscular disorder. - Highlights: • We reported 2 patients with mitochondrial neuromuscular disorders. • The heteroplasmic MT-ATP6 9157G>A variation was reported. • A triplication of 9 bp in the mitochondrial NC7 region was detected. • The m.14924T>C transition (S60P) in the MT-CYB gene was found.

  13. DNA Precursor Metabolism and Mitochondrial Genome Stability

    National Research Council Canada - National Science Library

    Mathews, Christopher K

    2003-01-01

    ...) metabolism and mutagenesis in the mitochondrial genome. Specific contributions include: (1) We found that conditions altering the normal balance among the four dNTP pools within the mitochondrion stimulate both point and deletion mutagenesis...

  14. Deoxynucleoside salvage enzymes and tissue specific mitochondrial DNA depletion.

    Science.gov (United States)

    Wang, L

    2010-06-01

    Adequate mitochondrial DNA (mtDNA) copies are required for normal mitochondria function and reductions in mtDNA copy number due to genetic alterations cause tissue-specific mtDNA depletion syndrome (MDS). There are eight nuclear genes, directly or indirectly involved in mtDNA replication and mtDNA precursor synthesis, which have been identified as the cause of MDS. However, the tissue specific pathology of these nuclear gene mutations is not well understood. Here, mtDNA synthesis, mtDNA copy number control, and mtDNA turnover, as well as the synthesis of mtDNA precursors in relation to the levels of salvage enzymes are discussed. The question why MDS caused by TK2 and p53R2 mutations are predominantly muscle specific while dGK deficiency affected mainly liver will be addressed.

  15. Mitochondrial DNA Copy Number in Sleep Duration Discordant Monozygotic Twins

    DEFF Research Database (Denmark)

    Wrede, Joanna E; Mengel-From, Jonas; Buchwald, Dedra

    2015-01-01

    STUDY OBJECTIVES: Mitochondrial DNA (mtDNA) copy number is an important component of mitochondrial function and varies with age, disease, and environmental factors. We aimed to determine whether mtDNA copy number varies with habitual differences in sleep duration within pairs of monozygotic twins...... structure to assess within-pair effects of sleep duration on mtDNA copy number. MEASUREMENTS AND RESULTS: Mean within-pair sleep duration difference per 24 hours was 94.3 minutes (SD 62.6 min). We found reduced sleep duration (β = 0.06; 95% CI 0.004, 0.12; P sleep efficiency (β = 0.51; 95% CI 0.......06, 0.95; P DNA copy number within twin pairs. Thus every 1-minute decrease in actigraphy-defined sleep duration was associated with a decrease in mtDNA copy number of 0.06. Likewise, a 1% decrease in actigraphy-defined sleep efficiency was associated...

  16. Phylogeny and evolution of the auks (subfamily Alcinae) based on mitochondrial DNA sequences

    Science.gov (United States)

    Moum, Truls; Johansen, Steinar; Erikstad, Kjell Einar; Piatt, John F.

    1994-01-01

    The genetic divergence and phylogeny of the auks was assessed by mitochondrial DNA sequence comparisons in a study using 19 of the 22 auk species and two outgroup representatives. We compared more than 500 nucleotides from each of two mitochondrial genes encoding 12S rRNA and the NADH dehydrogenase subunit 6. Divergence times were estimated from transversional substitutions. The dovekie (Alle alle) is related to the razorbill (Alca torda) and the murres (Uria spp). Furthermore, the Xantus's murrelet (Synthliboramphus hypoleucus) and the ancient (Synthliboramphus antiquus) and Japanese murrelets (Synthliboramphus wumizusume) are genetically distinct members of the same main lineage, whereas brachyramphine and synthliboramphine murrelets are not closely related. An early adaptive radiation of six main species groups of auks seems to trace back to Middle Miocene. Later speciation probably involved ecological differentiations and geographical isolations.

  17. Mitochondrial DNA as an inflammatory mediator in cardiovascular diseases.

    Science.gov (United States)

    Nakayama, Hiroyuki; Otsu, Kinya

    2018-03-06

    Mitochondria play a central role in multiple cellular functions, including energy production, calcium homeostasis, and cell death. Currently, growing evidence indicates the vital roles of mitochondria in triggering and maintaining inflammation. Chronic inflammation without microbial infection - termed sterile inflammation - is strongly involved in the development of heart failure. Sterile inflammation is triggered by the activation of pattern recognition receptors (PRRs) that sense endogenous ligands called damage-associated molecular patterns (DAMPs). Mitochondria release multiple DAMPs including mitochondrial DNA, peptides, and lipids, which induce inflammation via the stimulation of multiple PRRs. Among the mitochondrial DAMPs, mitochondrial DNA (mtDNA) is currently highlighted as the DAMP that mediates the activation of multiple PRRs, including Toll-like receptor 9, Nod-like receptors, and cyclic GMP-AMP synthetase/stimulator of interferon gene pathways. These PRR signalling pathways, in turn, lead to the activation of nuclear factor-κB and interferon regulatory factor, which enhances the transcriptional activity of inflammatory cytokines and interferons, and induces the recruitment of inflammatory cells. As the heart is an organ comprising abundant mitochondria for its ATP consumption (needed to maintain constant cyclic contraction and relaxation), the generation of massive amounts of mitochondrial radical oxygen species and mitochondrial DAMPs are predicted to occur and promote cardiac inflammation. Here, we will focus on the role of mtDNA in cardiac inflammation and review the mechanism and pathological significance of mtDNA-induced inflammatory responses in cardiac diseases. © 2018 The Author(s).

  18. Mitochondrial DNA Copy Number in Sleep Duration Discordant Monozygotic Twins.

    Science.gov (United States)

    Wrede, Joanna E; Mengel-From, Jonas; Buchwald, Dedra; Vitiello, Michael V; Bamshad, Michael; Noonan, Carolyn; Christiansen, Lene; Christensen, Kaare; Watson, Nathaniel F

    2015-10-01

    Mitochondrial DNA (mtDNA) copy number is an important component of mitochondrial function and varies with age, disease, and environmental factors. We aimed to determine whether mtDNA copy number varies with habitual differences in sleep duration within pairs of monozygotic twins. Academic clinical research center. 15 sleep duration discordant monozygotic twin pairs (30 twins, 80% female; mean age 42.1 years [SD 15.0]). Sleep duration was phenotyped with wrist actigraphy. Each twin pair included a "normal" (7-9 h/24) and "short" (sleeping twin. Fasting peripheral blood leukocyte DNA was assessed for mtDNA copy number via the n-fold difference between qPCR measured mtDNA and nuclear DNA creating an mtDNA measure without absolute units. We used generalized estimating equation linear regression models accounting for the correlated data structure to assess within-pair effects of sleep duration on mtDNA copy number. Mean within-pair sleep duration difference per 24 hours was 94.3 minutes (SD 62.6 min). We found reduced sleep duration (β = 0.06; 95% CI 0.004, 0.12; P sleep efficiency (β = 0.51; 95% CI 0.06, 0.95; P sleep duration was associated with a decrease in mtDNA copy number of 0.06. Likewise, a 1% decrease in actigraphy-defined sleep efficiency was associated with a decrease in mtDNA copy number of 0.51. Reduced sleep duration and sleep efficiency were associated with reduced mitochondrial DNA copy number in sleep duration discordant monozygotic twins offering a potential mechanism whereby short sleep impairs health and longevity through mitochondrial stress. © 2015 Associated Professional Sleep Societies, LLC.

  19. Mitochondrial DNA analysis suggests a Chibchan migration into Colombia

    OpenAIRE

    Noguera-Santamaría, Maria Claudia; Instituto de Genética Humana, Facultad de Medicina, Pontificia Universidad Javeriana. Grupo de Genética Humana, Facultad de Medicina, Universidad de La Sabana. Facultad de Ciencias de la Salud. Grupo Gisafaco. Corporación Universitaria Remington; Anderson, Carl Edlund; Department of Foreign Languages & Cultures, Universidad de La Sabana; Uricoechea, Daniel; Grupo de Genética Humana, Facultad de Medicina, Universidad de La Sabana; Durán, Clemencia; Instituto de Genética Humana, Facultad de Medicina, Pontificia Universidad Javeriana.; Briceño-Balcázar, Ignacio; Instituto de Genética Humana, Facultad de Medicina, Pontificia Universidad Javeriana Grupo de Genética Humana, Facultad de Medicina, Universidad de La Sabana; Bernal-Villegas, Jaime; Instituto de Genética Humana, Facultad de Medicina, Pontificia Universidad Javeriana Universidad Tecnológica de Bolívar

    2015-01-01

    The characterization of mitochondrial DNA (mtDNA) allows the establishment of genetic structures and phylogenetic relationships in human populations, tracing lineages far back in time. We analysed samples of mtDNA from twenty (20) Native American populations (700 individuals) dispersed throughout Colombian territory. Samples were collected during 1989-1993 in the context of the program Expedición Humana (“Human Expedition”) and stored in the Biological Repository of the Institute of Human Gen...

  20. Ancient DNA from European Early Neolithic Farmers Reveals Their Near Eastern Affinities

    Science.gov (United States)

    Haak, Wolfgang; Balanovsky, Oleg; Sanchez, Juan J.; Koshel, Sergey; Zaporozhchenko, Valery; Adler, Christina J.; Der Sarkissian, Clio S. I.; Brandt, Guido; Schwarz, Carolin; Nicklisch, Nicole; Dresely, Veit; Fritsch, Barbara; Balanovska, Elena; Villems, Richard; Meller, Harald; Alt, Kurt W.; Cooper, Alan

    2010-01-01

    In Europe, the Neolithic transition (8,000–4,000 b.c.) from hunting and gathering to agricultural communities was one of the most important demographic events since the initial peopling of Europe by anatomically modern humans in the Upper Paleolithic (40,000 b.c.). However, the nature and speed of this transition is a matter of continuing scientific debate in archaeology, anthropology, and human population genetics. To date, inferences about the genetic make up of past populations have mostly been drawn from studies of modern-day Eurasian populations, but increasingly ancient DNA studies offer a direct view of the genetic past. We genetically characterized a population of the earliest farming culture in Central Europe, the Linear Pottery Culture (LBK; 5,500–4,900 calibrated b.c.) and used comprehensive phylogeographic and population genetic analyses to locate its origins within the broader Eurasian region, and to trace potential dispersal routes into Europe. We cloned and sequenced the mitochondrial hypervariable segment I and designed two powerful SNP multiplex PCR systems to generate new mitochondrial and Y-chromosomal data from 21 individuals from a complete LBK graveyard at Derenburg Meerenstieg II in Germany. These results considerably extend the available genetic dataset for the LBK (n = 42) and permit the first detailed genetic analysis of the earliest Neolithic culture in Central Europe (5,500–4,900 calibrated b.c.). We characterized the Neolithic mitochondrial DNA sequence diversity and geographical affinities of the early farmers using a large database of extant Western Eurasian populations (n = 23,394) and a wide range of population genetic analyses including shared haplotype analyses, principal component analyses, multidimensional scaling, geographic mapping of genetic distances, and Bayesian Serial Simcoal analyses. The results reveal that the LBK population shared an affinity with the modern-day Near East and Anatolia, supporting a major

  1. Ancient DNA from European early neolithic farmers reveals their near eastern affinities.

    Directory of Open Access Journals (Sweden)

    Wolfgang Haak

    Full Text Available In Europe, the Neolithic transition (8,000-4,000 B.C. from hunting and gathering to agricultural communities was one of the most important demographic events since the initial peopling of Europe by anatomically modern humans in the Upper Paleolithic (40,000 B.C.. However, the nature and speed of this transition is a matter of continuing scientific debate in archaeology, anthropology, and human population genetics. To date, inferences about the genetic make up of past populations have mostly been drawn from studies of modern-day Eurasian populations, but increasingly ancient DNA studies offer a direct view of the genetic past. We genetically characterized a population of the earliest farming culture in Central Europe, the Linear Pottery Culture (LBK; 5,500-4,900 calibrated B.C. and used comprehensive phylogeographic and population genetic analyses to locate its origins within the broader Eurasian region, and to trace potential dispersal routes into Europe. We cloned and sequenced the mitochondrial hypervariable segment I and designed two powerful SNP multiplex PCR systems to generate new mitochondrial and Y-chromosomal data from 21 individuals from a complete LBK graveyard at Derenburg Meerenstieg II in Germany. These results considerably extend the available genetic dataset for the LBK (n = 42 and permit the first detailed genetic analysis of the earliest Neolithic culture in Central Europe (5,500-4,900 calibrated B.C.. We characterized the Neolithic mitochondrial DNA sequence diversity and geographical affinities of the early farmers using a large database of extant Western Eurasian populations (n = 23,394 and a wide range of population genetic analyses including shared haplotype analyses, principal component analyses, multidimensional scaling, geographic mapping of genetic distances, and Bayesian Serial Simcoal analyses. The results reveal that the LBK population shared an affinity with the modern-day Near East and Anatolia, supporting

  2. Investigation of ancient DNA from Western Siberia and the Sargat culture.

    Science.gov (United States)

    Bennett, Casey C; Kaestle, Frederika A

    2010-04-01

    Mitochondrial DNA from 14 archaeological samples at the Ural State University in Yekaterinburg, Russia, was extracted to test the feasibility of ancient DNA work on their collection. These samples come from a number of sites that fall into two groupings. Seven samples are from three sites, dating to the 8th-12th century AD, that belong to a northern group of what are thought to be Ugrians, who lived along the Ural Mountains in northwestern Siberia. The remaining seven samples are from two sites that belong to a southern group representing the Sargat culture, dating between roughly the 5th century BC and the 5th century AD, from southwestern Siberia near the Ural Mountains and the present-day Kazakhstan border. The samples are derived from several burial types, including kurgan burials. They also represent a number of different skeletal elements and a range of observed preservation. The northern sites repeatedly failed to amplify after multiple extraction and amplification attempts, but the samples from the southern sites were successfully extracted and amplified. The sequences obtained from the southern sites support the hypothesis that the Sargat culture was a potential zone of intermixture between native Ugrian and/or Siberian populations and steppe peoples from the south, possibly early Iranian or Indo-Iranian, which has been previously suggested by archaeological analysis.

  3. Induced pluripotent stem cells with a pathological mitochondrial DNA deletion

    Science.gov (United States)

    Cherry, Anne B. C.; Gagne, Katelyn E.; McLoughlin, Erin M.; Baccei, Anna; Gorman, Bryan; Hartung, Odelya; Miller, Justine D.; Zhang, Jin; Zon, Rebecca L.; Ince, Tan A.; Neufeld, Ellis J.; Lerou, Paul H.; Fleming, Mark D.; Daley, George Q.; Agarwal, Suneet

    2013-01-01

    In congenital mitochondrial DNA (mtDNA) disorders, a mixture of normal and mutated mtDNA (termed heteroplasmy) exists at varying levels in different tissues, which determines the severity and phenotypic expression of disease. Pearson marrow pancreas syndrome (PS) is a congenital bone marrow failure disorder caused by heteroplasmic deletions in mtDNA. The cause of the hematopoietic failure in PS is unknown, and adequate cellular and animal models are lacking. Induced pluripotent stem (iPS) cells are particularly amenable for studying mtDNA disorders, as cytoplasmic genetic material is retained during direct reprogramming. Here we derive and characterize iPS cells from a patient with PS. Taking advantage of the tendency for heteroplasmy to change with cell passage, we isolated isogenic PS-iPS cells without detectable levels of deleted mtDNA. We found that PS-iPS cells carrying a high burden of deleted mtDNA displayed differences in growth, mitochondrial function, and hematopoietic phenotype when differentiated in vitro, compared to isogenic iPS cells without deleted mtDNA. Our results demonstrate that reprogramming somatic cells from patients with mtDNA disorders can yield pluripotent stem cells with varying burdens of heteroplasmy that might be useful in the study and treatment of mitochondrial diseases. PMID:23400930

  4. Ancient DNA analyses reveal contrasting phylogeographic patterns amongst kiwi (Apteryx spp. and a recently extinct lineage of spotted kiwi.

    Directory of Open Access Journals (Sweden)

    Lara D Shepherd

    Full Text Available The little spotted kiwi (Apteryx owenii is a flightless ratite formerly found throughout New Zealand but now greatly reduced in distribution. Previous phylogeographic studies of the related brown kiwi (A. mantelli, A. rowi and A. australis, with which little spotted kiwi was once sympatric, revealed extremely high levels of genetic structuring, with mitochondrial DNA haplotypes often restricted to populations. We surveyed genetic variation throughout the present and pre-human range of little spotted kiwi by obtaining mitochondrial DNA sequences from contemporary and ancient samples. Little spotted kiwi and great spotted kiwi (A. haastii formed a monophyletic clade sister to brown kiwi. Ancient samples of little spotted kiwi from the northern North Island, where it is now extinct, formed a lineage that was distinct from remaining little spotted kiwi and great spotted kiwi lineages, potentially indicating unrecognized taxonomic diversity. Overall, little spotted kiwi exhibited much lower levels of genetic diversity and structuring than brown kiwi, particularly through the South Island. Our results also indicate that little spotted kiwi (or at least hybrids involving this species survived on the South Island mainland until more recently than previously thought.

  5. Accurate quantification of mouse mitochondrial DNA without co-amplification of nuclear mitochondrial insertion sequences.

    Science.gov (United States)

    Malik, Afshan N; Czajka, Anna; Cunningham, Phil

    2016-07-01

    Mitochondria contain an extra-nuclear genome in the form of mitochondrial DNA (MtDNA), damage to which can lead to inflammation and bioenergetic deficit. Changes in MtDNA levels are increasingly used as a biomarker of mitochondrial dysfunction. We previously reported that in humans, fragments in the nuclear genome known as nuclear mitochondrial insertion sequences (NumtS) affect accurate quantification of MtDNA. In the current paper our aim was to determine whether mouse NumtS affect the quantification of MtDNA and to establish a method designed to avoid this. The existence of NumtS in the mouse genome was confirmed using blast N, unique MtDNA regions were identified using FASTA, and MtDNA primers which do not co-amplify NumtS were designed and tested. MtDNA copy numbers were determined in a range of mouse tissues as the ratio of the mitochondrial and nuclear genome using real time qPCR and absolute quantification. Approximately 95% of mouse MtDNA was duplicated in the nuclear genome as NumtS which were located in 15 out of 21 chromosomes. A unique region was identified and primers flanking this region were used. MtDNA levels differed significantly in mouse tissues being the highest in the heart, with levels in descending order (highest to lowest) in kidney, liver, blood, brain, islets and lung. The presence of NumtS in the nuclear genome of mouse could lead to erroneous data when studying MtDNA content or mutation. The unique primers described here will allow accurate quantification of MtDNA content in mouse models without co-amplification of NumtS. Copyright © 2016 Elsevier B.V. and Mitochondria Research Society. All rights reserved.

  6. Genetics Home Reference: RRM2B-related mitochondrial DNA depletion syndrome, encephalomyopathic form with renal ...

    Science.gov (United States)

    ... Additional NIH Resources (1 link) National Institute of Neurological Disorders and Stroke: Mitochondrial Myopathy Information Page Educational Resources (7 links) Cincinnati Children's Hospital: Mitochondrial Diseases Disease InfoSearch: Mitochondrial DNA depletion ...

  7. "Stiff neonate" with mitochondrial DNA depletion and secondary neurotransmitter defects.

    LENUS (Irish Health Repository)

    Moran, Margaret M

    2011-12-01

    Mitochondrial disorders comprise a heterogenous group. A neonate who presented with episodes of severe truncal hypertonia and apnea progressed to a hypokinetic rigid syndrome characterized by hypokinesia, tremulousness, profound head lag, absent suck and gag reflexes, brisk deep tendon reflexes, ankle and jaw clonus, and evidence of autonomic dysfunction. Analysis of cerebrospinal fluid neurotransmitters from age 7 weeks demonstrated low levels of amine metabolites (homovanillic acid and 5-hydroxyindoleacetic acid), tetrahydrobiopterin, and pyridoxal phosphate. Mitochondrial DNA quantitative studies on muscle homogenate demonstrated a mitochondrial DNA depletion disorder. Respiratory chain enzymology demonstrated decreased complex IV activity. Screening for mitochondrial DNA rearrangement disorders and sequencing relevant mitochondrial genes produced negative results. No clinical or biochemical response to treatment with pyridoxal phosphate, tetrahydrobiopterin, or l-dopa occurred. The clinical course was progressive, and the patient died at age 19 months. Mitochondrial disorders causing secondary neurotransmitter diseases are usually severe, but are rarely reported. This diagnosis should be considered in neonates or infants who present with hypertonia, hypokinesia rigidity, and progressive neurodegeneration.

  8. Maternal inheritance and mitochondrial DNA variants in familial Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Pfeiffer Ronald F

    2010-04-01

    Full Text Available Abstract Background Mitochondrial function is impaired in Parkinson's disease (PD and may contribute to the pathogenesis of PD, but the causes of mitochondrial impairment in PD are unknown. Mitochondrial dysfunction is recapitulated in cell lines expressing mitochondrial DNA (mtDNA from PD patients, implicating mtDNA variants or mutations, though the role of mtDNA variants or mutations in PD risk remains unclear. We investigated the potential contribution of mtDNA variants or mutations to the risk of PD. Methods We examined the possibility of a maternal inheritance bias as well as the association between mitochondrial haplogroups and maternal inheritance and disease risk in a case-control study of 168 multiplex PD families in which the proband and one parent were diagnosed with PD. 2-tailed Fisher Exact Tests and McNemar's tests were used to compare allele frequencies, and a t-test to compare ages of onset. Results The frequency of affected mothers of the proband with PD (83/167, 49.4% was not significantly different from the frequency of affected females of the proband generation (115/259, 44.4% (Odds Ratio 1.22; 95%CI 0.83 - 1.81. After correcting for multiple tests, there were no significant differences in the frequencies of mitochondrial haplogroups or of the 10398G complex I gene polymorphism in PD patients compared to controls, and no significant associations with age of onset of PD. Mitochondrial haplogroup and 10398G polymorphism frequencies were similar in probands having an affected father as compared to probands having an affected mother. Conclusions These data fail to demonstrate a bias towards maternal inheritance in familial PD. Consistent with this, we find no association of common haplogroup-defining mtDNA variants or for the 10398G variant with the risk of PD. However, these data do not exclude a role for mtDNA variants in other populations, and it remains possible that other inherited mitochondrial DNA variants, or somatic mDNA

  9. More on contamination: the use of asymmetric molecular behavior to identify authentic ancient human DNA

    DEFF Research Database (Denmark)

    Malmström, Helena; Svensson, Emma M; Gilbert, M Thomas P

    2007-01-01

    concerning the authenticity of such data. Although several methods have been developed to the purpose of authenticating ancient DNA (aDNA) results, while they are useful in faunal research, most of the methods have proven complicated to apply to ancient human DNA. Here, we investigate in detail...... the reliability of one of the proposed criteria, that of appropriate molecular behavior. Using real-time polymerase chain reaction (PCR) and pyrosequencing, we have quantified the relative levels of authentic aDNA and contaminant human DNA sequences recovered from archaeological dog and cattle remains. In doing...

  10. Blood cell mitochondrial DNA content and premature ovarian aging.

    Directory of Open Access Journals (Sweden)

    Marco Bonomi

    Full Text Available Primary ovarian insufficiency (POI is a critical fertility defect characterized by an anticipated and silent impairment of the follicular reserve, but its pathogenesis is largely unexplained. The frequent maternal inheritance of POI together with a remarkable dependence of ovarian folliculogenesis upon mitochondrial biogenesis and bioenergetics suggested the possible involvement of a generalized mitochondrial defect. Here, we verified the existence of a significant correlation between blood and ovarian mitochondrial DNA (mtDNA content in a group of women undergoing ovarian hyperstimulation (OH, and then aimed to verify whether mtDNA content was significantly altered in the blood cells of POI women. We recruited 101 women with an impaired ovarian reserve: 59 women with premature ovarian failure (POF and 42 poor responders (PR to OH. A Taqman copy number assay revealed a significant mtDNA depletion (P<0.001 in both POF and PR women in comparison with 43 women of similar age and intact ovarian reserve, or 53 very old women with a previous physiological menopause. No pathogenic variations in the mitochondrial DNA polymerase γ (POLG gene were detected in 57 POF or PR women with low blood mtDNA content. In conclusion, blood cell mtDNA depletion is a frequent finding among women with premature ovarian aging, suggesting that a still undetermined but generalized mitochondrial defect may frequently predispose to POI which could then be considered a form of anticipated aging in which the ovarian defect may represent the first manifestation. The determination of mtDNA content in blood may become an useful tool for the POI risk prediction.

  11. A comprehensive characterization of rare mitochondrial DNA variants in neuroblastoma.

    Science.gov (United States)

    Calabrese, Francesco Maria; Clima, Rosanna; Pignataro, Piero; Lasorsa, Vito Alessandro; Hogarty, Michael D; Castellano, Aurora; Conte, Massimo; Tonini, Gian Paolo; Iolascon, Achille; Gasparre, Giuseppe; Capasso, Mario

    2016-08-02

    Neuroblastoma, a tumor of the developing sympathetic nervous system, is a common childhood neoplasm that is often lethal. Mitochondrial DNA (mtDNA) mutations have been found in most tumors including neuroblastoma. We extracted mtDNA data from a cohort of neuroblastoma samples that had undergone Whole Exome Sequencing (WES) and also used snap-frozen samples in which mtDNA was entirely sequenced by Sanger technology. We next undertook the challenge of determining those mutations that are relevant to, or arisen during tumor development. The bioinformatics pipeline used to extract mitochondrial variants from matched tumor/blood samples was enriched by a set of filters inclusive of heteroplasmic fraction, nucleotide variability, and in silico prediction of pathogenicity. Our in silico multistep workflow applied both on WES and Sanger-sequenced neuroblastoma samples, allowed us to identify a limited burden of somatic and germline mitochondrial mutations with a potential pathogenic impact. The few singleton germline and somatic mitochondrial mutations emerged, according to our in silico analysis, do not appear to impact on the development of neuroblastoma. Our findings are consistent with the hypothesis that most mitochondrial somatic mutations can be considered as 'passengers' and consequently have no discernible effect in this type of cancer.

  12. Mitochondrial DNA inheritance in the human fungal pathogen Cryptococcus gattii.

    Science.gov (United States)

    Wang, Zixuan; Wilson, Amanda; Xu, Jianping

    2015-02-01

    The inheritance of mitochondrial DNA (mtDNA) is predominantly uniparental in most sexual eukaryotes. In this study, we examined the mitochondrial inheritance pattern of Cryptococcus gattii, a basidiomycetous yeast responsible for the recent and ongoing outbreak of cryptococcal infections in the US Pacific Northwest and British Columbia (especially Vancouver Island) in Canada. Using molecular markers, we analyzed the inheritance of mtDNA in 14 crosses between strains within and between divergent lineages in C. gattii. Consistent with results from recent studies, our analyses identified significant variations in mtDNA inheritance patterns among strains and crosses, ranging from strictly uniparental to biparental. For two of the crosses that showed uniparental mitochondrial inheritance in standard laboratory conditions, we further investigated the effects of the following environmental variables on mtDNA inheritance: UV exposure, temperature, and treatments with the methylation inhibitor 5-aza-2'-deoxycytidine and with the ubiquitination inhibitor ammonium chloride. Interestingly, one of these crosses showed no response to these environmental variables while the other exhibited diverse patterns ranging from complete uniparental inheritance of the MATa parent mtDNA, to biparental inheritance, and to a significant bias toward inheritance of the MATα parental mtDNA. Our results indicate that mtDNA inheritance in C. gattii differs from that in its closely related species Cryptococcus neoformans. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Recovering mitochondrial DNA lineages of extinct Amerindian nations in extant homopatric Brazilian populations.

    Science.gov (United States)

    Gonçalves, Vanessa F; Parra, Flavia C; Gonçalves-Dornelas, Higgor; Rodrigues-Carvalho, Claudia; Silva, Hilton P; Pena, Sergio Dj

    2010-12-01

    Brazilian Amerindians have experienced a drastic population decrease in the past 500 years. Indeed, many native groups from eastern Brazil have vanished. However, their mitochondrial mtDNA haplotypes, still persist in Brazilians, at least 50 million of whom carry Amerindian mitochondrial lineages. Our objective was to test whether, by analyzing extant rural populations from regions anciently occupied by specific Amerindian groups, we could identify potentially authentic mitochondrial lineages, a strategy we have named 'homopatric targeting'. We studied 173 individuals from Queixadinha, a small village located in a territory previously occupied by the now extinct Botocudo Amerindian nation. Pedigree analysis revealed 74 unrelated matrilineages, which were screened for Amerindian mtDNA lineages by restriction fragment length polymorphism. A cosmopolitan control group was composed of 100 individuals from surrounding cities. All Amerindian lineages identified had their hypervariable segment HVSI sequenced, yielding 13 Amerindian haplotypes in Queixadinha, nine of which were not present in available databanks or in the literature. Among these haplotypes, there was a significant excess of haplogroup C (70%) and absence of haplogroup A lineages, which were the most common in the control group. The novelty of the haplotypes and the excess of the C haplogroup suggested that we might indeed have identified Botocudo lineages. To validate our strategy, we studied teeth extracted from 14 ancient skulls of Botocudo Amerindians from the collection of the National Museum of Rio de Janeiro. We recovered mtDNA sequences from all the teeth, identifying only six different haplotypes (a low haplotypic diversity of 0.8352 ± 0.0617), one of which was present among the lineages observed in the extant individuals studied. These findings validate the technique of homopatric targeting as a useful new strategy to study the peopling and colonization of the New World, especially when direct

  14. Unravelling the complexity of domestication: a case study using morphometrics and ancient DNA analyses of archaeological pigs from Romania

    Science.gov (United States)

    Evin, Allowen; Flink, Linus Girdland; Bălăşescu, Adrian; Popovici, Dragomir; Andreescu, Radian; Bailey, Douglas; Mirea, Pavel; Lazăr, Cătălin; Boroneanţ, Adina; Bonsall, Clive; Vidarsdottir, Una Strand; Brehard, Stéphanie; Tresset, Anne; Cucchi, Thomas; Larson, Greger; Dobney, Keith

    2015-01-01

    Current evidence suggests that pigs were first domesticated in Eastern Anatolia during the ninth millennium cal BC before dispersing into Europe with Early Neolithic farmers from the beginning of the seventh millennium. Recent ancient DNA (aDNA) research also indicates the incorporation of European wild boar into domestic stock during the Neolithization process. In order to establish the timing of the arrival of domestic pigs into Europe, and to test hypotheses regarding the role European wild boar played in the domestication process, we combined a geometric morphometric analysis (allowing us to combine tooth size and shape) of 449 Romanian ancient teeth with aDNA analysis. Our results firstly substantiate claims that the first domestic pigs in Romania possessed the same mtDNA signatures found in Neolithic pigs in west and central Anatolia. Second, we identified a significant proportion of individuals with large molars whose tooth shape matched that of archaeological (likely) domestic pigs. These large ‘domestic shape’ specimens were present from the outset of the Romanian Neolithic (6100–5500 cal BC) through to later prehistory, suggesting a long history of admixture between introduced domestic pigs and local wild boar. Finally, we confirmed a turnover in mitochondrial lineages found in domestic pigs, possibly coincident with human migration into Anatolia and the Levant that occurred in later prehistory. PMID:25487340

  15. Mitochondrial DNA Mutation Associated with Leber's Hereditary Optic Neuropathy

    Science.gov (United States)

    Wallace, Douglas C.; Singh, Gurparkash; Lott, Marie T.; Hodge, Judy A.; Schurr, Theodore G.; Lezza, Angela M. S.; Elsas, Louis J.; Nikoskelainen, Eeva K.

    1988-12-01

    Leber's hereditary optic neuropathy is a maternally inherited disease resulting in optic nerve degeneration and cardiac dysrhythmia. A mitochondrial DNA replacement mutation was identified that correlated with this disease in multiple families. This mutation converted a highly conserved arginine to a histidine at codon 340 in the NADH dehydrogenase subunit 4 gene and eliminated an Sfa NI site, thus providing a simple diagnostic test. This finding demonstrated that a nucleotide change in a mitochondrial DNA energy production gene can result in a neurological disease.

  16. Pros and cons of methylation-based enrichment methods for ancient DNA

    DEFF Research Database (Denmark)

    Seguin-Orlando, Andaine; Gamba, Cristina; Der Sarkissian, Clio

    2015-01-01

    samples, where both DNA fragmentation and deamination have been limited. This work represents an essential step toward the characterization of ancient methylation signatures, which will help understanding the role of epigenetic changes in past environmental and cultural transitions....

  17. DNA FROM ANCIENT STONE TOOLS AND BONES EXCAVATED AT BUGAS-HOLDING, WYOMING

    Science.gov (United States)

    Traces of DNA may preserve on ancient stone tools. We examined 24 chipped stone artifacts recovered from the Bugas-Holding site in northwestern Wyoming for the presence of DNA residues, and we compared DNA preservation in bones and stone tools from the same stratigraphic context...

  18. Experimental conditions improving in-solution target enrichment for ancient DNA

    DEFF Research Database (Denmark)

    Cruz-Dávalos, Diana I.; Llamas, Bastien; Gaunitz, Charleen

    2017-01-01

    High-throughput sequencing has dramatically fostered ancient DNA research in recent years. Shotgun sequencing, however, does not necessarily appear as the best-suited approach due to the extensive contamination of samples with exogenous environmental microbial DNA. DNA capture-enrichment methods ...

  19. Tamil merchant in ancient Mesopotamia.

    Directory of Open Access Journals (Sweden)

    Malliya Gounder Palanichamy

    Full Text Available Recent analyses of ancient Mesopotamian mitochondrial genomes have suggested a genetic link between the Indian subcontinent and Mesopotamian civilization. There is no consensus on the origin of the ancient Mesopotamians. They may be descendants of migrants, who founded regional Mesopotamian groups like that of Terqa or they may be merchants who were involved in trans Mesopotamia trade. To identify the Indian source population showing linkage to the ancient Mesopotamians, we screened a total of 15,751 mitochondrial DNAs (11,432 from the literature and 4,319 from this study representing all major populations of India. Our results although suggest that south India (Tamil Nadu and northeast India served as the source of the ancient Mesopotamian mtDNA gene pool, mtDNA of these ancient Mesopotamians probably contributed by Tamil merchants who were involved in the Indo-Roman trade.

  20. DNA methyltransferase 1 mutations and mitochondrial pathology: is mtDNA methylated?

    Directory of Open Access Journals (Sweden)

    Alessandra eMaresca

    2015-03-01

    Full Text Available Autosomal dominant cerebellar ataxia, deafness and narcolepsy (ADCA-DN and Hereditary sensory neuropathy with dementia and hearing loss (HSN1E are two rare, overlapping neurodegenerative syndromes that have been recently linked to allelic dominant pathogenic mutations in the DNMT1 gene, coding for DNA (cytosine-5-methyltransferase 1. DNMT1 is the enzyme responsible for maintaining the nuclear genome methylation patterns during the DNA replication and repair, thus regulating gene expression. The mutations responsible for ADCA-DN and HSN1E affect the replication foci targeting sequence domain, which regulates DNMT1 binding to chromatin. DNMT1 dysfunction is anticipated to lead to a global alteration of the DNA methylation pattern with predictable downstream consequences on gene expression. Interestingly, ADCA-DN and HSN1E phenotypes share some clinical features typical of mitochondrial diseases, such as optic atrophy, peripheral neuropathy and deafness, and some biochemical evidence of mitochondrial dysfunction. The recent discovery of a mitochondrial isoform of DNMT1 and its proposed role in methylating mitochondrial DNA (mtDNA suggests that DNMT1 mutations may directly affect mtDNA and mitochondrial physiology. On the basis of this latter finding the link between DNMT1 abnormal activity and mitochondrial dysfunction in ADCA-DN and HSN1E appears intuitive, however mtDNA methylation remains highly debated. In the last years several groups demonstrated the presence of 5-methylcytosine in mtDNA by different approaches, but, on the other end, the opposite evidence that mtDNA is not methylated has also been published. Since over 1500 mitochondrial proteins are encoded by the nuclear genome, the altered methylation of these genes may well have a critical role in leading to the mitochondrial impairment observed in ADCA-DN and HSN1E. Thus, many open questions still remain unanswered, such as why mtDNA should be methylated, and how this process is

  1. Evidence Suggesting Absence of Mitochondrial DNA Methylation

    DEFF Research Database (Denmark)

    Mechta, Mie; Ingerslev, Lars R; Fabre, Odile

    2017-01-01

    , 16S, ND5 and CYTB, suggesting that mtDNA supercoiled structure blocks the access to bisulfite conversion. Here, we identified an artifact of mtDNA bisulfite sequencing that can lead to an overestimation of mtDNA methylation levels. Our study supports that cytosine methylation is virtually absent...

  2. Hybrid male sterility is caused by mitochondrial DNA deletion.

    Science.gov (United States)

    Hayashida, Kenji; Kohno, Shigeru

    2009-07-01

    Although it is known that the hybrid male mouse is sterile just like any other animal's heterogametic sex, the reason why only the male germ cells are impaired has yet to be discovered. TdT-mediated dUTP nick end labeling assay using a confocal fluorescence microscope and DNA fragmentation assay of hybrid testis indicated destruction of the mitochondrial DNA (mtDNA) rather than the nuclear DNA. Previously we reported that maternal mtDNA inheritance is through selective sperm mtDNA elimination based on the sperm factor and two egg factors, and expression of these three factors was recognized in the hybrid testis. It was thereby assumed that mtDNA destruction caused by the expression of maternal mtDNA inheritance system in male germ cells is implicated in the hybrid male sterility of mice.

  3. Computational analyses of ancient pathogen DNA from herbarium samples: challenges and prospects.

    Science.gov (United States)

    Yoshida, Kentaro; Sasaki, Eriko; Kamoun, Sophien

    2015-01-01

    The application of DNA sequencing technology to the study of ancient DNA has enabled the reconstruction of past epidemics from genomes of historically important plant-associated microbes. Recently, the genome sequences of the potato late blight pathogen Phytophthora infestans were analyzed from 19th century herbarium specimens. These herbarium samples originated from infected potatoes collected during and after the Irish potato famine. Herbaria have therefore great potential to help elucidate past epidemics of crops, date the emergence of pathogens, and inform about past pathogen population dynamics. DNA preservation in herbarium samples was unexpectedly good, raising the possibility of a whole new research area in plant and microbial genomics. However, the recovered DNA can be extremely fragmented resulting in specific challenges in reconstructing genome sequences. Here we review some of the challenges in computational analyses of ancient DNA from herbarium samples. We also applied the recently developed linkage method to haplotype reconstruction of diploid or polyploid genomes from fragmented ancient DNA.

  4. DNA sequence evolution in fast evolving mitochondrial DNA nad1 exons in Geraniaceae and Plantaginaceae

    NARCIS (Netherlands)

    Bakker, F.T.; Breman, F.; Merckx, V.

    2006-01-01

    Previously, nucleotide substitution rates in mitochondrial DNA of Geraniaceae and Plantaginaceae have been shown to be exceptionally high compared with other angiosperm mtDNA lineages. It has also been shown that mtDNA introns were lost in Geraniaceae and Plantaginaceae. In this study we compile 127

  5. Role of Mitochondrial DNA Mutations in Cellular Vulnerability to Mitochondria-Specific Environmental Toxins

    National Research Council Canada - National Science Library

    Hirsch, Etienne C

    2005-01-01

    In recent years, growing evidence has shown that mutations of mitochondrial DNA (mtDNA) are an important cause of mitochondrial disorders in humans, and have been associated with common neurodegenerative disorders, aging and cancers...

  6. Nuclear and mitochondrial DNA quantification of various forensic materials.

    Science.gov (United States)

    Andréasson, H; Nilsson, M; Budowle, B; Lundberg, H; Allen, M

    2006-12-01

    Due to the different types and quality of forensic evidence materials, their DNA content can vary substantially, and particularly low quantities can impact the results in an identification analysis. In this study, the quantity of mitochondrial and nuclear DNA was determined in a variety of materials using a previously described real-time PCR method. DNA quantification in the roots and distal sections of plucked and shed head hairs revealed large variations in DNA content particularly between the root and the shaft of plucked hairs. Also large intra- and inter-individual variations were found among hairs. In addition, DNA content was estimated in samples collected from fingerprints and accessories. The quantification of DNA on various items also displayed large variations, with some materials containing large amounts of nuclear DNA while no detectable nuclear DNA and only limited amounts of mitochondrial DNA were seen in others. Using this sensitive real-time PCR quantification assay, a better understanding was obtained regarding DNA content and variation in commonly analysed forensic evidence materials and this may guide the forensic scientist as to the best molecular biology approach for analysing various forensic evidence materials.

  7. Mitochondrial DNA repair and association with aging- an update

    DEFF Research Database (Denmark)

    Diaz, Ricardo Gredilla; Bohr, Vilhelm; Stevnsner, Tinna V.

    2010-01-01

    in the aging process and to be particularly deleterious in post-mitotic cells. Thus, DNA repair is an important mechanism for maintenance of genomic integrity. Despite the importance of mitochondria in the aging process, it was thought for many years that mitochondria lacked an enzymatic DNA repair system...... proteins and novel DNA repair pathways, thought to be exclusively present in the nucleus, have recently been described also to be present in mitochondria. Here we review the main mitochondrial DNA repair pathways and their association with the aging process....

  8. Mitochondrial DNA alteration in obstructive sleep apnea.

    Science.gov (United States)

    Lacedonia, Donato; Carpagnano, Giovanna E; Crisetti, Elisabetta; Cotugno, Grazia; Palladino, Grazia P; Patricelli, Giulia; Sabato, Roberto; Foschino Barbaro, Maria P

    2015-04-07

    Obstructive Sleep Apnea (OSAS) is a disease associated with the increase of cardiovascular risk and it is characterized by repeated episodes of Intermittent Hypoxia (IH) which inducing oxidative stress and systemic inflammation. Mitochondria are cell organelles involved in the respiratory that have their own DNA (MtDNA). The aim of this study was to investigate if the increase of oxidative stress in OSAS patients can induce also MtDNA alterations. 46 OSAS patients (age 59.27 ± 11.38; BMI 30.84 ± 3.64; AHI 36.63 ± 24.18) were compared with 36 control subjects (age 54.42 ± 6.63; BMI 29.06 ± 4.7; AHI 3.8 ± 1.10). In blood cells Content of MtDNA and nuclear DNA (nDNA) was measured in OSAS patients by Real Time PCR. The ratio between MtDNA/nDNA was then calculated. Presence of oxidative stress was evaluated by levels of Reactive Oxygen Metabolites (ROMs), measured by diacron reactive oxygen metabolite test (d-ROM test). MtDNA/nDNA was higher in patients with OSAS than in the control group (150.94 ± 49.14 vs 128.96 ± 45.8; p = 0.04), the levels of ROMs were also higher in OSAS subjects (329.71 ± 70.17 vs 226 ± 36.76; p = 0.04) and they were positively correlated with MtDNA/nDNA (R = 0.5, p DNA damage induced by the increase of oxidative stress. Intermittent hypoxia seems to be the main mechanism which leads to this process.

  9. Ancient DNA from Giant Panda (Ailuropoda melanoleuca) of South-Western China Reveals Genetic Diversity Loss during the Holocene.

    Science.gov (United States)

    Sheng, Gui-Lian; Barlow, Axel; Cooper, Alan; Hou, Xin-Dong; Ji, Xue-Ping; Jablonski, Nina G; Zhong, Bo-Jian; Liu, Hong; Flynn, Lawrence J; Yuan, Jun-Xia; Wang, Li-Rui; Basler, Nikolas; Westbury, Michael V; Hofreiter, Michael; Lai, Xu-Long

    2018-04-06

    The giant panda was widely distributed in China and south-eastern Asia during the middle to late Pleistocene, prior to its habitat becoming rapidly reduced in the Holocene. While conservation reserves have been established and population numbers of the giant panda have recently increased, the interpretation of its genetic diversity remains controversial. Previous analyses, surprisingly, have indicated relatively high levels of genetic diversity raising issues concerning the efficiency and usefulness of reintroducing individuals from captive populations. However, due to a lack of DNA data from fossil specimens, it is unknown whether genetic diversity was even higher prior to the most recent population decline. We amplified complete cyt b and 12s rRNA, partial 16s rRNA and ND1 , and control region sequences from the mitochondrial genomes of two Holocene panda specimens. We estimated genetic diversity and population demography by analyzing the ancient mitochondrial DNA sequences alongside those from modern giant pandas, as well as from other members of the bear family (Ursidae). Phylogenetic analyses show that one of the ancient haplotypes is sister to all sampled modern pandas and the second ancient individual is nested among the modern haplotypes, suggesting that genetic diversity may indeed have been higher earlier during the Holocene. Bayesian skyline plot analysis supports this view and indicates a slight decline in female effective population size starting around 6000 years B.P., followed by a recovery around 2000 years ago. Therefore, while the genetic diversity of the giant panda has been affected by recent habitat contraction, it still harbors substantial genetic diversity. Moreover, while its still low population numbers require continued conservation efforts, there seem to be no immediate threats from the perspective of genetic evolutionary potential.

  10. Ancient DNA from Giant Panda (Ailuropoda melanoleuca of South-Western China Reveals Genetic Diversity Loss during the Holocene

    Directory of Open Access Journals (Sweden)

    Gui-Lian Sheng

    2018-04-01

    Full Text Available The giant panda was widely distributed in China and south-eastern Asia during the middle to late Pleistocene, prior to its habitat becoming rapidly reduced in the Holocene. While conservation reserves have been established and population numbers of the giant panda have recently increased, the interpretation of its genetic diversity remains controversial. Previous analyses, surprisingly, have indicated relatively high levels of genetic diversity raising issues concerning the efficiency and usefulness of reintroducing individuals from captive populations. However, due to a lack of DNA data from fossil specimens, it is unknown whether genetic diversity was even higher prior to the most recent population decline. We amplified complete cytb and 12s rRNA, partial 16s rRNA and ND1, and control region sequences from the mitochondrial genomes of two Holocene panda specimens. We estimated genetic diversity and population demography by analyzing the ancient mitochondrial DNA sequences alongside those from modern giant pandas, as well as from other members of the bear family (Ursidae. Phylogenetic analyses show that one of the ancient haplotypes is sister to all sampled modern pandas and the second ancient individual is nested among the modern haplotypes, suggesting that genetic diversity may indeed have been higher earlier during the Holocene. Bayesian skyline plot analysis supports this view and indicates a slight decline in female effective population size starting around 6000 years B.P., followed by a recovery around 2000 years ago. Therefore, while the genetic diversity of the giant panda has been affected by recent habitat contraction, it still harbors substantial genetic diversity. Moreover, while its still low population numbers require continued conservation efforts, there seem to be no immediate threats from the perspective of genetic evolutionary potential.

  11. Crosslinks rather than strand breaks determine access to ancient DNA sequences from frozen sediments

    DEFF Research Database (Denmark)

    Hansen, Anders Johannes; Mitchell, D.L.; Wiuf, C.

    2006-01-01

    , and freely exposed sugar, phosphate, and hydroxyl groups. Intriguingly, interstrand crosslinks were found to accumulate about hundred times faster than single stranded breaks, suggesting that crosslinking rather than depurination is the primary limiting factor for ancient DNA amplification under frozen...... conditions. The results question the reliability of the commonly used models relying on depurination kinetics for predicting the long-term survival of DNA under permafrost conditions and suggest that new strategies for repair of ancient DNA must be considered if the yield of amplifiable DNA from permafrost...

  12. Ancient mtDNA genetic variants modulate mtDNA transcription and replication.

    Directory of Open Access Journals (Sweden)

    Sarit Suissa

    2009-05-01

    Full Text Available Although the functional consequences of mitochondrial DNA (mtDNA genetic backgrounds (haplotypes, haplogroups have been demonstrated by both disease association studies and cell culture experiments, it is not clear which of the mutations within the haplogroup carry functional implications and which are "evolutionary silent hitchhikers". We set forth to study the functionality of haplogroup-defining mutations within the mtDNA transcription/replication regulatory region by in vitro transcription, hypothesizing that haplogroup-defining mutations occurring within regulatory motifs of mtDNA could affect these processes. We thus screened >2500 complete human mtDNAs representing all major populations worldwide for natural variation in experimentally established protein binding sites and regulatory regions comprising a total of 241 bp in each mtDNA. Our screen revealed 77/241 sites showing point mutations that could be divided into non-fixed (57/77, 74% and haplogroup/sub-haplogroup-defining changes (i.e., population fixed changes, 20/77, 26%. The variant defining Caucasian haplogroup J (C295T increased the binding of TFAM (Electro Mobility Shift Assay and the capacity of in vitro L-strand transcription, especially of a shorter transcript that maps immediately upstream of conserved sequence block 1 (CSB1, a region associated with RNA priming of mtDNA replication. Consistent with this finding, cybrids (i.e., cells sharing the same nuclear genetic background but differing in their mtDNA backgrounds harboring haplogroup J mtDNA had a >2 fold increase in mtDNA copy number, as compared to cybrids containing haplogroup H, with no apparent differences in steady state levels of mtDNA-encoded transcripts. Hence, a haplogroup J regulatory region mutation affects mtDNA replication or stability, which may partially account for the phenotypic impact of this haplogroup. Our analysis thus demonstrates, for the first time, the functional impact of particular mtDNA

  13. Mitochondrial DNA: An Endogenous Trigger for Immune Paralysis.

    Science.gov (United States)

    Schäfer, Simon T; Franken, Lars; Adamzik, Michael; Schumak, Beatrix; Scherag, André; Engler, Andrea; Schönborn, Niels; Walden, Jennifer; Koch, Susanne; Baba, Hideo A; Steinmann, Jörg; Westendorf, Astrid M; Fandrey, Joachim; Bieber, Thomas; Kurts, Christian; Frede, Stilla; Peters, Jürgen; Limmer, Andreas

    2016-04-01

    Critically ill patients are at high risk to suffer from sepsis, even in the absence of an initial infectious source, but the molecular mechanisms for their increased sepsis susceptibility, including a suppressed immune system, remain unclear. Although microbes and pathogen-associated molecular pattern are accepted inducers of sepsis and septic immunosuppression, the role of endogenous Toll-like receptor (TLR) ligands, such as mitochondrial DNA (mtDNA), in altering the immune response is unknown. Mitochondrial DNA serum concentrations of the mitochondrial genes D-Loop and adenosine triphosphatase 6 were determined (quantitative polymerase chain reaction) in 165 septic patients and 50 healthy volunteers. Furthermore, cytotoxic T-cell activity was analyzed in wild-type and TLR9 knockout mice, with/without previous mtDNA administration, followed by injection of an ovalbumin-expressing adenoviral vector. Mitochondrial DNA serum concentrations were increased in septic patients (adenosine triphosphatase 6, 123-fold; D-Loop, 76-fold, P < 0.0001) compared with volunteers. Furthermore, a single mtDNA injection caused profound, TLR9-dependent immunosuppression of adaptive T-cell cytotoxicity in wild-type but not in TLR9 knockout mice and evoked various immunosuppressive mechanisms including the destruction of the splenic microstructure, deletion of cross-presenting dendritic cells, and up-regulation of programmed cell death ligand 1 and indoleamine 2,3-dioxygenase. Several of these findings in mice were mirrored in septic patients, and mtDNA concentrations were associated with an increased 30-day mortality. The findings of this study imply that mtDNA, an endogenous danger associated molecular pattern, is a hitherto unknown inducer of septic immunoparalysis and one possible link between initial inflammation and subsequent immunosuppression in critically ill patients.

  14. Mitochondrial DNA sequence-based phylogenetic relationship ...

    Indian Academy of Sciences (India)

    cophaga ranges from 0.037–0.106 and 0.049–0.207 for COI and ND5 genes, respectively (tables 2 and 3). Analysis of genetic distance on the basis of sequence difference for both the mitochondrial genes shows very little genetic difference. The discrepancy in the phylogenetic trees based on individ- ual genes may be due ...

  15. Fly Diversity Revealed by PCR-RFLP of Mitochondrial DNA

    Science.gov (United States)

    Asraoui, Jimmy F.; Sayar, Nancy P.; Knio, Khouzama M.; Smith, Colin A.

    2008-01-01

    In this article, we describe an inexpensive, two-session undergraduate laboratory activity that introduces important molecular biology methods in the context of biodiversity. In the first session, students bring tentatively identified flies (order Diptera, true flies) to the laboratory, extract DNA, and amplify a region of the mitochondrial gene…

  16. The efficiency of mitochondrial DNA markers in constructing genetic ...

    African Journals Online (AJOL)

    Administrator

    2011-05-30

    May 30, 2011 ... To date, only parts of mitochondrial DNA from cytochrome b, 12S rRNA, 16S rRNA and non-coding D- loop had been sequenced for different species of Oryx. Discrepancy in the genetic relationship among. Oryx species was previously revealed when combinations of these sequences were analyzed. In the.

  17. Ligation bias in illumina next-generation DNA libraries: implications for sequencing ancient genomes.

    Directory of Open Access Journals (Sweden)

    Andaine Seguin-Orlando

    Full Text Available Ancient DNA extracts consist of a mixture of endogenous molecules and contaminant DNA templates, often originating from environmental microbes. These two populations of templates exhibit different chemical characteristics, with the former showing depurination and cytosine deamination by-products, resulting from post-mortem DNA damage. Such chemical modifications can interfere with the molecular tools used for building second-generation DNA libraries, and limit our ability to fully characterize the true complexity of ancient DNA extracts. In this study, we first use fresh DNA extracts to demonstrate that library preparation based on adapter ligation at AT-overhangs are biased against DNA templates starting with thymine residues, contrarily to blunt-end adapter ligation. We observe the same bias on fresh DNA extracts sheared on Bioruptor, Covaris and nebulizers. This contradicts previous reports suggesting that this bias could originate from the methods used for shearing DNA. This also suggests that AT-overhang adapter ligation efficiency is affected in a sequence-dependent manner and results in an uneven representation of different genomic contexts. We then show how this bias could affect the base composition of ancient DNA libraries prepared following AT-overhang ligation, mainly by limiting the ability to ligate DNA templates starting with thymines and therefore deaminated cytosines. This results in particular nucleotide misincorporation damage patterns, deviating from the signature generally expected for authenticating ancient sequence data. Consequently, we show that models adequate for estimating post-mortem DNA damage levels must be robust to the molecular tools used for building ancient DNA libraries.

  18. Replication stalling by catalytically impaired Twinkle induces mitochondrial DNA rearrangements in cultured cells

    NARCIS (Netherlands)

    Pohjoismaki, J.L.; Goffart, S.; Spelbrink, J.N.

    2011-01-01

    Pathological mitochondrial DNA (mtDNA) rearrangements have been proposed to result from repair of double-strand breaks caused by blockage of mitochondrial DNA (mtDNA) replication. As mtDNA deletions are seen only in post-mitotic tissues, it has been suggested that they are selected out in actively

  19. Pathological mechanisms underlying single large‐scale mitochondrial DNA deletions

    Science.gov (United States)

    Rocha, Mariana C.; Rosa, Hannah S.; Grady, John P.; Blakely, Emma L.; He, Langping; Romain, Nadine; Haller, Ronald G.; Newman, Jane; McFarland, Robert; Ng, Yi Shiau; Gorman, Grainne S.; Schaefer, Andrew M.; Tuppen, Helen A.; Taylor, Robert W.

    2018-01-01

    Objective Single, large‐scale deletions in mitochondrial DNA (mtDNA) are a common cause of mitochondrial disease. This study aimed to investigate the relationship between the genetic defect and molecular phenotype to improve understanding of pathogenic mechanisms associated with single, large‐scale mtDNA deletions in skeletal muscle. Methods We investigated 23 muscle biopsies taken from adult patients (6 males/17 females with a mean age of 43 years) with characterized single, large‐scale mtDNA deletions. Mitochondrial respiratory chain deficiency in skeletal muscle biopsies was quantified by immunoreactivity levels for complex I and complex IV proteins. Single muscle fibers with varying degrees of deficiency were selected from 6 patient biopsies for determination of mtDNA deletion level and copy number by quantitative polymerase chain reaction. Results We have defined 3 “classes” of single, large‐scale deletion with distinct patterns of mitochondrial deficiency, determined by the size and location of the deletion. Single fiber analyses showed that fibers with greater respiratory chain deficiency harbored higher levels of mtDNA deletion with an increase in total mtDNA copy number. For the first time, we have demonstrated that threshold levels for complex I and complex IV deficiency differ based on deletion class. Interpretation Combining genetic and immunofluorescent assays, we conclude that thresholds for complex I and complex IV deficiency are modulated by the deletion of complex‐specific protein‐encoding genes. Furthermore, removal of mt‐tRNA genes impacts specific complexes only at high deletion levels, when complex‐specific protein‐encoding genes remain. These novel findings provide valuable insight into the pathogenic mechanisms associated with these mutations. Ann Neurol 2018;83:115–130 PMID:29283441

  20. Paleoparasitological report on Ascaris aDNA from an ancient East Asian sample

    Directory of Open Access Journals (Sweden)

    Chang Seok Oh

    2010-03-01

    Full Text Available In this study, Ascaris DNA was extracted and sequenced from a medieval archaeological sample in Korea. While Ascaris eggs were confirmed to be of human origin by archaeological evidence, it was not possible to pinpoint the exact species due to close genetic relationships among them. Despite this shortcoming, this is the first Ascaris ancient DNA (aDNA report from a medieval Asian country and thus will expand the scope of Ascaris aDNA research.

  1. The use of mitochondrial DNA (mtDNA-investigations in Forensic Sciences

    Directory of Open Access Journals (Sweden)

    S. Dawson

    1996-07-01

    Full Text Available A variety of methods was developed to characterize mtDNA. The initial aim of these techniques was to try and link diseases with specific mitochondrial defects. As a result of the maternal inheritance trait of mtDNA these techniques facilitate studies of the phylogenetic history and population structure of the human population. It has been shown that mitochondrial DNA typing can be of great value for human identification in forensic cases. The identification of victims of mass-disasters or mass-murders, where human remains can be recovered only after many years have passed, is one of the most challenging fields of forensic identification. By using automated DNA sequencing with fluorescent labels, mitochondrial DNA sequences can be generated rapidly and accurately. Computer software facilitates the rapid comparison of individual and reference sequences.

  2. Mitochondrial DNA: A Blind Spot in Neuroepigenetics

    OpenAIRE

    Manev, Hari; Dzitoyeva, Svetlana; Chen, Hu

    2012-01-01

    Neuroepigenetics, which includes nuclear DNA modifications such as 5-methylcytosine and 5-hydoxymethylcytosine and modifications of nuclear proteins such as histones, is emerging as the leading field in molecular neuroscience. Historically, a functional role for epigenetic mechanisms, including in neuroepigenetics, has been sought in the area of the regulation of nuclear transcription. However, one important compartment of mammalian cell DNA, different from nuclear but equally important for p...

  3. A comprehensive characterization of mitochondrial DNA mutations in glioblastoma multiforme.

    Science.gov (United States)

    Vidone, Michele; Clima, Rosanna; Santorsola, Mariangela; Calabrese, Claudia; Girolimetti, Giulia; Kurelac, Ivana; Amato, Laura Benedetta; Iommarini, Luisa; Trevisan, Elisa; Leone, Marco; Soffietti, Riccardo; Morra, Isabella; Faccani, Giuliano; Attimonelli, Marcella; Porcelli, Anna Maria; Gasparre, Giuseppe

    2015-06-01

    Glioblastoma multiforme (GBM) is the most malignant brain cancer in adults, with a poor prognosis, whose molecular stratification still represents a challenge in pathology and clinics. On the other hand, mitochondrial DNA (mtDNA) mutations have been found in most tumors as modifiers of the bioenergetics state, albeit in GBM a characterization of the mtDNA status is lacking to date. Here, a characterization of the burden of mtDNA mutations in GBM samples was performed. First, investigation of tumor-specific vs. non tumor-specific mutations was carried out with the MToolBox bioinformatics pipeline by analyzing 45 matched tumor/blood samples, from whole genome or whole exome sequencing datasets obtained from The Cancer Genome Atlas (TCGA) consortium. Additionally, the entire mtDNA sequence was obtained in a dataset of 104 fresh-frozen GBM samples. Mitochondrial mutations with potential pathogenic interest were prioritized based on heteroplasmic fraction, nucleotide variability, and in silico prediction of pathogenicity. A preliminary biochemical analysis of the activity of mitochondrial respiratory complexes was also performed on fresh-frozen GBM samples. Although a high number of mutations was detected, we report that the large majority of them does not pass the prioritization filters. Therefore, a relatively limited burden of pathogenic mutations is indeed carried by GBM, which did not appear to determine a general impairment of the respiratory chain. This article is part of a Directed Issue entitled: Energy Metabolism Disorders and Therapies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Mitochondrial DNA diversity of present-day Aboriginal Australians and implications for human evolution in Oceania.

    Science.gov (United States)

    Nagle, Nano; Ballantyne, Kaye N; van Oven, Mannis; Tyler-Smith, Chris; Xue, Yali; Wilcox, Stephen; Wilcox, Leah; Turkalov, Rust; van Oorschot, Roland A H; van Holst Pellekaan, Sheila; Schurr, Theodore G; McAllister, Peter; Williams, Lesley; Kayser, Manfred; Mitchell, R John

    2017-03-01

    Aboriginal Australians are one of the more poorly studied populations from the standpoint of human evolution and genetic diversity. Thus, to investigate their genetic diversity, the possible date of their ancestors' arrival and their relationships with neighboring populations, we analyzed mitochondrial DNA (mtDNA) diversity in a large sample of Aboriginal Australians. Selected mtDNA single-nucleotide polymorphisms and the hypervariable segment haplotypes were analyzed in 594 Aboriginal Australians drawn from locations across the continent, chiefly from regions not previously sampled. Most (~78%) samples could be assigned to mtDNA haplogroups indigenous to Australia. The indigenous haplogroups were all ancient (with estimated ages >40 000 years) and geographically widespread across the continent. The most common haplogroup was P (44%) followed by S (23%) and M42a (9%). There was some geographic structure at the haplotype level. The estimated ages of the indigenous haplogroups range from 39 000 to 55 000 years, dates that fit well with the estimated date of colonization of Australia based on archeological evidence (~47 000 years ago). The distribution of mtDNA haplogroups in Australia and New Guinea supports the hypothesis that the ancestors of Aboriginal Australians entered Sahul through at least two entry points. The mtDNA data give no support to the hypothesis of secondary gene flow into Australia during the Holocene, but instead suggest long-term isolation of the continent.

  5. Private mitochondrial DNA variants in danish patients with hypertrophic cardiomyopathy

    DEFF Research Database (Denmark)

    Hagen, Christian M; Aidt, Frederik H; Havndrup, Ole

    2015-01-01

    Hypertrophic cardiomyopathy (HCM) is a genetic cardiac disease primarily caused by mutations in genes coding for sarcomeric proteins. A molecular-genetic etiology can be established in ~60% of cases. Evolutionarily conserved mitochondrial DNA (mtDNA) haplogroups are susceptibility factors for HCM......>G, and MT-CYB: m.15024G>A, p.C93Y remained. A detailed analysis of these variants indicated that none of them are likely to cause HCM. In conclusion, private mtDNA mutations are frequent, but they are rarely, if ever, associated with HCM....

  6. Characterization of Bombyx mori mitochondrial transcription factor A, a conserved regulator of mitochondrial DNA.

    Science.gov (United States)

    Sumitani, Megumi; Kondo, Mari; Kasashima, Katsumi; Endo, Hitoshi; Nakamura, Kaoru; Misawa, Toshihiko; Tanaka, Hiromitsu; Sezutsu, Hideki

    2017-04-15

    In the present study, we initially cloned and characterized a mitochondrial transcription factor A (Tfam) homologue in the silkworm, Bombyx mori. Bombyx mori TFAM (BmTFAM) localized to mitochondria in cultured silkworm and human cells, and co-localized with mtDNA nucleoids in human HeLa cells. In an immunoprecipitation analysis, BmTFAM was found to associate with human mtDNA in mitochondria, indicating its feature as a non-specific DNA-binding protein. In spite of the low identity between BmTFAM and human TFAM (26.5%), the expression of BmTFAM rescued mtDNA copy number reductions and enlarged mtDNA nucleoids in HeLa cells, which were induced by human Tfam knockdown. Thus, BmTFAM compensates for the function of human TFAM in HeLa cells, demonstrating that the mitochondrial function of TFAM is highly conserved between silkworms and humans. BmTfam mRNA was strongly expressed in early embryos. Through double-stranded RNA (dsRNA)-based RNA interference (RNAi) in silkworm embryos, we found that the knockdown of BmTFAM reduced the amount of mtDNA and induced growth retardation at the larval stage. Collectively, these results demonstrate that BmTFAM is a highly conserved mtDNA regulator and may be a good candidate for investigating and modulating mtDNA metabolism in this model organism. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Stories in Genetic Code. The contribution of ancient DNA studies to anthropology and their ethical implications

    Directory of Open Access Journals (Sweden)

    Cristian M. Crespo

    2010-12-01

    Full Text Available For several decades, biological anthropology has employed different molecular markers in population research. Since 1990 different techniques in molecular biology have been developed allowing preserved DNA extraction and its typification in different samples from museums and archaeological sites. Ancient DNA studies related to archaeological issues are now included in the field of Archaeogenetics. In this work we present some of ancient DNA applications in archaeology. We also discuss advantages and limitations for this kind of research and its relationship with ethic and legal norms.

  8. Fact Sheet- Ancient DNA: What is it? Why is it Important?

    OpenAIRE

    Alexa Walker; George Nicholas; Daryl Pullman; Alan Goodman; Bioarchaeology and Genetics Working Group

    2016-01-01

    As genetic research is increasingly applied to new areas of study, including in archaeological and heritage contexts, a range of questions arise concerning the social, ethical, legal, and political implications of ancient DNA. This fact sheet explains the nature and challenges of aDNA research, and why information from it is important and relevant to people today. 

  9. Repetitive transpositions of mitochondrial DNA sequences to the nucleus during the radiation of horseshoe bats (Rhinolophus, Chiroptera).

    Science.gov (United States)

    Shi, Huizhen; Dong, Ji; Irwin, David M; Zhang, Shuyi; Mao, Xiuguang

    2016-05-01

    Transposition of mitochondrial DNA into the nucleus, which gives rise to nuclear mitochondrial DNAs (NUMTs), has been well documented in eukaryotes. However, very few studies have assessed the frequency of these transpositions during the evolutionary history of a specific taxonomic group. Here we used the horseshoe bats (Rhinolophus) as a case study to determine the frequency and relative timing of nuclear transfers of mitochondrial control region sequences. For this, phylogenetic and coalescent analyzes were performed on NUMTs and authentic mtDNA sequences generated from eight horseshoe bat species. Our results suggest at least three independent transpositions, including two ancient and one more recent, during the evolutionary history of Rhinolophus. The two ancient transpositions are represented by the NUMT-1 and -2 clades, with each clade consisting of NUMTs from almost all studied species but originating from different portions of the mtDNA genome. Furthermore, estimates of the most recent common ancestor for each clade corresponded to the time of the initial diversification of this genus. The recent transposition is represented by NUMT-3, which was discovered only in a specific subgroup of Rhinolophus and exhibited a close relationship to its mitochondrial counterpart. Our similarity searches of mtDNA in the R. ferrumequinum genome confirmed the presence of NUMT-1 and NUMT-2 clade sequences and, for the first time, assessed the extent of NUMTs in a bat genome. To our knowledge, this is the first study to report on the frequency of transpositions of mtDNA occurring before the common ancestry of a genus. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Mitochondrial DNA depletion, mitochondrial mutations and high TFAM expression in hepatocellular carcinoma

    OpenAIRE

    Qiao, Lihua; Ru, Guoqing; Mao, Zhuochao; Wang, Chenghui; Nie, Zhipeng; Li, Qiang; Huang-yang, Yiyi; Zhu, Ling; Liang, Xiaoyang; Yu, Jialing; Jiang, Pingping

    2017-01-01

    We investigated the role of mitochondrial genetic alterations in hepatocellular carcinoma by directly comparing the mitochondrial genomes of 86 matched pairs of HCC and non-tumor liver samples. Substitutions in 637 mtDNA sites were detected, comprising 89.80% transitions and 6.60% transversions. Forty-six somatic variants, including 15 novel mutations, were identified in 40.70% of tumor tissues. Of those, 21 were located in the non-coding region and 25 in the protein-coding region. Twenty-two...

  11. Genotyping of Capreolus pygargus fossil DNA from Denisova cave reveals phylogenetic relationships between ancient and modern populations.

    Directory of Open Access Journals (Sweden)

    Nadezhda V Vorobieva

    Full Text Available BACKGROUND: The extant roe deer (Capreolus Gray, 1821 includes two species: the European roe deer (C. capreolus and the Siberian roe deer (C. pygargus that are distinguished by morphological and karyotypical differences. The Siberian roe deer occupies a vast area of Asia and is considerably less studied than the European roe deer. Modern systematics of the Siberian roe deer remain controversial with 4 morphological subspecies. Roe deer fossilized bones are quite abundant in Denisova cave (Altai Mountains, South Siberia, where dozens of both extant and extinct mammalian species from modern Holocene to Middle Pleistocene have been retrieved. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed a 629 bp fragment of the mitochondrial control region from ancient bones of 10 Holocene and four Pleistocene Siberian roe deer from Denisova cave as well as 37 modern specimen belonging to populations from Altai, Tian Shan (Kyrgyzstan, Yakutia, Novosibirsk region and the Russian Far East. Genealogical reconstructions indicated that most Holocene haplotypes were probably ancestral for modern roe deer populations of Western Siberia and Tian Shan. One of the Pleistocene haplotypes was possibly ancestral for modern Yakutian populations, and two extinct Pleistocene haplotypes were close to modern roe deer from Tian Shan and Yakutia. Most modern geographical populations (except for West Siberian Plains are heterogeneous and there is some tentative evidence for structure. However, we did not find any distinct phylogenetic signal characterizing particular subspecies in either modern or ancient samples. CONCLUSION/SIGNIFICANCE: Analysis of mitochondrial DNA from both ancient and modern samples of Siberian roe deer shed new light on understanding the evolutionary history of roe deer. Our data indicate that during the last 50,000 years multiple replacements of populations of the Siberian roe deer took place in the Altai Mountains correlating with climatic changes. The Siberian

  12. The effect of ancient DNA damage on inferences of demographic histories

    DEFF Research Database (Denmark)

    Axelsson, Erik; Willerslev, Eske; Gilbert, Marcus Thomas Pius

    2008-01-01

    The field of ancient DNA (aDNA) is casting new light on many evolutionary questions. However, problems associated with the postmortem instability of DNA may complicate the interpretation of aDNA data. For example, in population genetic studies, the inclusion of damaged DNA may inflate estimates o...... for a change in effective population size in this data set vanishes once the effects of putative damage are removed. Our results suggest that population genetic analyses of aDNA sequences, which do not accurately account for damage, should be interpreted with great caution....

  13. Evolution and inheritance of animal mitochondrial DNA: rules and exceptions.

    Science.gov (United States)

    Ladoukakis, Emmanuel D; Zouros, Eleftherios

    2017-12-01

    Mitochondrial DNA (mtDNA) has been studied intensely for "its own" merit. Its role for the function of the cell and the organism remains a fertile field, its origin and evolution is an indispensable part of the evolution of life and its interaction with the nuclear DNA is among the most important cases of genome synergism and co-evolution. Also, mtDNA was proven one of the most useful tools in population genetics and molecular phylogenetics. In this article we focus on animal mtDNA and discuss briefly how our views about its structure, function and transmission have changed, how these changes affect the information we have accumulated through its use in the fields of phylogeny and population structure and what are the most important questions that remain open for future research.

  14. Atomistic Molecular Dynamics Simulations of Mitochondrial DNA Polymerase γ

    DEFF Research Database (Denmark)

    Euro, Liliya; Haapanen, Outi; Róg, Tomasz

    2017-01-01

    of replisomal interactions, and functional effects of patient mutations that do not affect direct catalysis have remained elusive. Here we report the first atomistic classical molecular dynamics simulations of the human Pol γ replicative complex. Our simulation data show that DNA binding triggers remarkable......DNA polymerase γ (Pol γ) is a key component of the mitochondrial DNA replisome and an important cause of neurological diseases. Despite the availability of its crystal structures, the molecular mechanism of DNA replication, the switch between polymerase and exonuclease activities, the site...... changes in the enzyme structure, including (1) completion of the DNA-binding channel via a dynamic subdomain, which in the apo form blocks the catalytic site, (2) stabilization of the structure through the distal accessory β-subunit, and (3) formation of a putative transient replisome-binding platform...

  15. Mitochondrial DNA replication: a PrimPol perspective

    Science.gov (United States)

    Bailey, Laura J.

    2017-01-01

    PrimPol, (primase–polymerase), the most recently identified eukaryotic polymerase, has roles in both nuclear and mitochondrial DNA maintenance. PrimPol is capable of acting as a DNA polymerase, with the ability to extend primers and also bypass a variety of oxidative and photolesions. In addition, PrimPol also functions as a primase, catalysing the preferential formation of DNA primers in a zinc finger-dependent manner. Although PrimPol's catalytic activities have been uncovered in vitro, we still know little about how and why it is targeted to the mitochondrion and what its key roles are in the maintenance of this multicopy DNA molecule. Unlike nuclear DNA, the mammalian mitochondrial genome is circular and the organelle has many unique proteins essential for its maintenance, presenting a differing environment within which PrimPol must function. Here, we discuss what is currently known about the mechanisms of DNA replication in the mitochondrion, the proteins that carry out these processes and how PrimPol is likely to be involved in assisting this vital cellular process. PMID:28408491

  16. qPCR-based mitochondrial DNA quantification: Influence of template DNA fragmentation on accuracy

    International Nuclear Information System (INIS)

    Jackson, Christopher B.; Gallati, Sabina; Schaller, André

    2012-01-01

    Highlights: ► Serial qPCR accurately determines fragmentation state of any given DNA sample. ► Serial qPCR demonstrates different preservation of the nuclear and mitochondrial genome. ► Serial qPCR provides a diagnostic tool to validate the integrity of bioptic material. ► Serial qPCR excludes degradation-induced erroneous quantification. -- Abstract: Real-time PCR (qPCR) is the method of choice for quantification of mitochondrial DNA (mtDNA) by relative comparison of a nuclear to a mitochondrial locus. Quantitative abnormal mtDNA content is indicative of mitochondrial disorders and mostly confines in a tissue-specific manner. Thus handling of degradation-prone bioptic material is inevitable. We established a serial qPCR assay based on increasing amplicon size to measure degradation status of any DNA sample. Using this approach we can exclude erroneous mtDNA quantification due to degraded samples (e.g. long post-exicision time, autolytic processus, freeze–thaw cycles) and ensure abnormal DNA content measurements (e.g. depletion) in non-degraded patient material. By preparation of degraded DNA under controlled conditions using sonification and DNaseI digestion we show that erroneous quantification is due to the different preservation qualities of the nuclear and the mitochondrial genome. This disparate degradation of the two genomes results in over- or underestimation of mtDNA copy number in degraded samples. Moreover, as analysis of defined archival tissue would allow to precise the molecular pathomechanism of mitochondrial disorders presenting with abnormal mtDNA content, we compared fresh frozen (FF) with formalin-fixed paraffin-embedded (FFPE) skeletal muscle tissue of the same sample. By extrapolation of measured decay constants for nuclear DNA (λ nDNA ) and mtDNA (λ mtDNA ) we present an approach to possibly correct measurements in degraded samples in the future. To our knowledge this is the first time different degradation impact of the two

  17. qPCR-based mitochondrial DNA quantification: Influence of template DNA fragmentation on accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Christopher B., E-mail: Christopher.jackson@insel.ch [Division of Human Genetics, Departements of Pediatrics and Clinical Research, Inselspital, University of Berne, Freiburgstrasse, CH-3010 Berne (Switzerland); Gallati, Sabina, E-mail: sabina.gallati@insel.ch [Division of Human Genetics, Departements of Pediatrics and Clinical Research, Inselspital, University of Berne, Freiburgstrasse, CH-3010 Berne (Switzerland); Schaller, Andre, E-mail: andre.schaller@insel.ch [Division of Human Genetics, Departements of Pediatrics and Clinical Research, Inselspital, University of Berne, Freiburgstrasse, CH-3010 Berne (Switzerland)

    2012-07-06

    Highlights: Black-Right-Pointing-Pointer Serial qPCR accurately determines fragmentation state of any given DNA sample. Black-Right-Pointing-Pointer Serial qPCR demonstrates different preservation of the nuclear and mitochondrial genome. Black-Right-Pointing-Pointer Serial qPCR provides a diagnostic tool to validate the integrity of bioptic material. Black-Right-Pointing-Pointer Serial qPCR excludes degradation-induced erroneous quantification. -- Abstract: Real-time PCR (qPCR) is the method of choice for quantification of mitochondrial DNA (mtDNA) by relative comparison of a nuclear to a mitochondrial locus. Quantitative abnormal mtDNA content is indicative of mitochondrial disorders and mostly confines in a tissue-specific manner. Thus handling of degradation-prone bioptic material is inevitable. We established a serial qPCR assay based on increasing amplicon size to measure degradation status of any DNA sample. Using this approach we can exclude erroneous mtDNA quantification due to degraded samples (e.g. long post-exicision time, autolytic processus, freeze-thaw cycles) and ensure abnormal DNA content measurements (e.g. depletion) in non-degraded patient material. By preparation of degraded DNA under controlled conditions using sonification and DNaseI digestion we show that erroneous quantification is due to the different preservation qualities of the nuclear and the mitochondrial genome. This disparate degradation of the two genomes results in over- or underestimation of mtDNA copy number in degraded samples. Moreover, as analysis of defined archival tissue would allow to precise the molecular pathomechanism of mitochondrial disorders presenting with abnormal mtDNA content, we compared fresh frozen (FF) with formalin-fixed paraffin-embedded (FFPE) skeletal muscle tissue of the same sample. By extrapolation of measured decay constants for nuclear DNA ({lambda}{sub nDNA}) and mtDNA ({lambda}{sub mtDNA}) we present an approach to possibly correct measurements in

  18. Sequence preservation of osteocalcin protein and mitochondrial DNA in bison bones older than 55 ka

    Science.gov (United States)

    Nielsen-Marsh, Christina M.; Ostrom, Peggy H.; Gandhi, Hasand; Shapiro, Beth; Cooper, Alan; Hauschka, Peter V.; Collins, Matthew J.

    2002-12-01

    We report the first complete sequences of the protein osteocalcin from small amounts (20 mg) of two bison bone (Bison priscus) dated to older than 55.6 ka and older than 58.9 ka. Osteocalcin was purified using new gravity columns (never exposed to protein) followed by microbore reversed-phase high-performance liquid chromatography. Sequencing of osteocalcin employed two methods of matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS): peptide mass mapping (PMM) and post-source decay (PSD). The PMM shows that ancient and modern bison osteocalcin have the same mass to charge (m/z) distribution, indicating an identical protein sequence and absence of diagenetic products. This was confirmed by PSD of the m/z 2066 tryptic peptide (residues 1 19); the mass spectra from ancient and modern peptides were identical. The 129 mass unit difference in the molecular ion between cow (Bos taurus) and bison is caused by a single amino-acid substitution between the taxa (Trp in cow is replaced by Gly in bison at residue 5). Bison mitochondrial control region DNA sequences were obtained from the older than 55.6 ka fossil. These results suggest that DNA and protein sequences can be used to directly investigate molecular phylogenies over a considerable time period, the absolute limit of which is yet to be determined.

  19. Performance of mitochondrial DNA mutations detecting early stage cancer

    International Nuclear Information System (INIS)

    Jakupciak, John P; Srivastava, Sudhir; Sidransky, David; O'Connell, Catherine D; Maragh, Samantha; Markowitz, Maura E; Greenberg, Alissa K; Hoque, Mohammad O; Maitra, Anirban; Barker, Peter E; Wagner, Paul D; Rom, William N

    2008-01-01

    Mutations in the mitochondrial genome (mtgenome) have been associated with cancer and many other disorders. These mutations can be point mutations or deletions, or admixtures (heteroplasmy). The detection of mtDNA mutations in body fluids using resequencing microarrays, which are more sensitive than other sequencing methods, could provide a strategy to measure mutation loads in remote anatomical sites. We determined the mtDNA mutation load in the entire mitochondrial genome of 26 individuals with different early stage cancers (lung, bladder, kidney) and 12 heavy smokers without cancer. MtDNA was sequenced from three matched specimens (blood, tumor and body fluid) from each cancer patient and two matched specimens (blood and sputum) from smokers without cancer. The inherited wildtype sequence in the blood was compared to the sequences present in the tumor and body fluid, detected using the Affymetrix Genechip ® Human Mitochondrial Resequencing Array 1.0 and supplemented by capillary sequencing for noncoding region. Using this high-throughput method, 75% of the tumors were found to contain mtDNA mutations, higher than in our previous studies, and 36% of the body fluids from these cancer patients contained mtDNA mutations. Most of the mutations detected were heteroplasmic. A statistically significantly higher heteroplasmy rate occurred in tumor specimens when compared to both body fluid of cancer patients and sputum of controls, and in patient blood compared to blood of controls. Only 2 of the 12 sputum specimens from heavy smokers without cancer (17%) contained mtDNA mutations. Although patient mutations were spread throughout the mtDNA genome in the lung, bladder and kidney series, a statistically significant elevation of tRNA and ND complex mutations was detected in tumors. Our findings indicate comprehensive mtDNA resequencing can be a high-throughput tool for detecting mutations in clinical samples with potential applications for cancer detection, but it is

  20. Characterization of a Dairy Gyr herd with respect to its mitochondrial DNA (mt DNA origin

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    Anibal Eugênio Vercesi Filho

    2010-01-01

    Full Text Available The Zebu breeds were introduced in Brazil mainly in the last century by imports from the Indian subcontinent. When the Zebu cattle arrived, the national herd suffered a significative change by backcrossing the national cows of taurine origin with Zebu sires. These processes created a polymorphism in the mitochondrial DNA (mtDNA in the Zebu animals with are in a major part derived from backcrossing and sharing mtDNA of taurine origin. To verify the maternal origin of cows belonging to the Dairy Gyr herd of APTA, Mococa 60 females were analyzed and 33 presented mtDNA from Bos taurus origin and 27 presented mtDNA from Bos indicus origin. None of these animals presented patterns of both mtDNA origins, indicating absence of heteroplasmy for these mitochondrial genotypes.

  1. Transcription profiles of mitochondrial genes correlate with mitochondrial DNA haplotypes in a natural population of Silene vulgaris

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    Olson Matthew S

    2010-01-01

    Full Text Available Abstract Background Although rapid changes in copy number and gene order are common within plant mitochondrial genomes, associated patterns of gene transcription are underinvestigated. Previous studies have shown that the gynodioecious plant species Silene vulgaris exhibits high mitochondrial diversity and occasional paternal inheritance of mitochondrial markers. Here we address whether variation in DNA molecular markers is correlated with variation in transcription of mitochondrial genes in S. vulgaris collected from natural populations. Results We analyzed RFLP variation in two mitochondrial genes, cox1 and atp1, in offspring of ten plants from a natural population of S. vulgaris in Central Europe. We also investigated transcription profiles of the atp1 and cox1 genes. Most DNA haplotypes and transcription profiles were maternally inherited; for these, transcription profiles were associated with specific mitochondrial DNA haplotypes. One individual exhibited a pattern consistent with paternal inheritance of mitochondrial DNA; this individual exhibited a transcription profile suggestive of paternal but inconsistent with maternal inheritance. We found no associations between gender and transcript profiles. Conclusions Specific transcription profiles of mitochondrial genes were associated with specific mitochondrial DNA haplotypes in a natural population of a gynodioecious species S. vulgaris. Our findings suggest the potential for a causal association between rearrangements in the plant mt genome and transcription product variation.

  2. Transcription profiling suggests that mitochondrial topoisomerase IB acts as a topological barrier and regulator of mitochondrial DNA transcription.

    Science.gov (United States)

    Dalla Rosa, Ilaria; Zhang, Hongliang; Khiati, Salim; Wu, Xiaolin; Pommier, Yves

    2017-12-08

    Mitochondrial DNA (mtDNA) is essential for cell viability because it encodes subunits of the respiratory chain complexes. Mitochondrial topoisomerase IB (TOP1MT) facilitates mtDNA replication by removing DNA topological tensions produced during mtDNA transcription, but it appears to be dispensable. To test whether cells lacking TOP1MT have aberrant mtDNA transcription, we performed mitochondrial transcriptome profiling. To that end, we designed and implemented a customized tiling array, which enabled genome-wide, strand-specific, and simultaneous detection of all mitochondrial transcripts. Our technique revealed that Top1mt KO mouse cells process the mitochondrial transcripts normally but that protein-coding mitochondrial transcripts are elevated. Moreover, we found discrete long noncoding RNAs produced by H-strand transcription and encompassing the noncoding regulatory region of mtDNA in human and murine cells and tissues. Of note, these noncoding RNAs were strongly up-regulated in the absence of TOP1MT. In contrast, 7S DNA, produced by mtDNA replication, was reduced in the Top1mt KO cells. We propose that the long noncoding RNA species in the D-loop region are generated by the extension of H-strand transcripts beyond their canonical stop site and that TOP1MT acts as a topological barrier and regulator for mtDNA transcription and D-loop formation.

  3. Temporal Fluctuation in North East Baltic Sea Region Cattle Population Revealed by Mitochondrial and Y-Chromosomal DNA Analyses

    Science.gov (United States)

    Niemi, Marianna; Bläuer, Auli; Iso-Touru, Terhi; Harjula, Janne; Nyström Edmark, Veronica; Rannamäe, Eve; Lõugas, Lembi; Sajantila, Antti; Lidén, Kerstin; Taavitsainen, Jussi-Pekka

    2015-01-01

    Background Ancient DNA analysis offers a way to detect changes in populations over time. To date, most studies of ancient cattle have focused on their domestication in prehistory, while only a limited number of studies have analysed later periods. Conversely, the genetic structure of modern cattle populations is well known given the undertaking of several molecular and population genetic studies. Results Bones and teeth from ancient cattle populations from the North-East Baltic Sea region dated to the Prehistoric (Late Bronze and Iron Age, 5 samples), Medieval (14), and Post-Medieval (26) periods were investigated by sequencing 667 base pairs (bp) from the mitochondrial DNA (mtDNA) and 155 bp of intron 19 in the Y-chromosomal UTY gene. Comparison of maternal (mtDNA haplotypes) genetic diversity in ancient cattle (45 samples) with modern cattle populations in Europe and Asia (2094 samples) revealed 30 ancient mtDNA haplotypes, 24 of which were shared with modern breeds, while 6 were unique to the ancient samples. Of seven Y-chromosomal sequences determined from ancient samples, six were Y2 and one Y1 haplotype. Combined data including Swedish samples from the same periods (64 samples) was compared with the occurrence of Y-chromosomal haplotypes in modern cattle (1614 samples). Conclusions The diversity of haplogroups was highest in the Prehistoric samples, where many haplotypes were unique. The Medieval and Post-Medieval samples also show a high diversity with new haplotypes. Some of these haplotypes have become frequent in modern breeds in the Nordic Countries and North-Western Russia while other haplotypes have remained in only a few local breeds or seem to have been lost. A temporal shift in Y-chromosomal haplotypes from Y2 to Y1 was detected that corresponds with the appearance of new mtDNA haplotypes in the Medieval and Post-Medieval period. This suggests a replacement of the Prehistoric mtDNA and Y chromosomal haplotypes by new types of cattle. PMID:25992976

  4. DNA repair of UV photoproducts and mutagenesis in human mitochondrial DNA

    International Nuclear Information System (INIS)

    Pascucci, B.; Dogliotti, E.; Versteegh, A.; Hoffen, A. van; Zeeland, A.A. van; Mullenders, L.H.F.

    1997-01-01

    The induction and repair of DNA photolesions and mutations in the mitochondrial (mt) DNA of human cells in culture were analysed after cell exposure to UV-C light. The level of induction of cyclobutane pyrimidine dimers (CPD) in mitochondrial and nuclear DNA was comparable, while a higher frequency of pyrimidine (6-4) pyrimidone photoproducts (6-4 PP) was detected in mitochondrial than in nuclear DNA. Besides the known defect in CPD removal, mitochondria were shown to be deficient also in the excision of 6-4 PP. The effects of repair-defective conditions for the two major UV photolesions on mutagensis was assessed by analysing the frequency and spectrum of spontaneous and UV-induced mutations by restriction site mutation (RSM) method in a restriction endonuclease site, NciI (5'CCCGG3') located within the coding sequence of the mitochondrial gene for tRNA Leu . The spontaneous mutation frequency and spectrum at the NciI site of mitochondrial DNA was very similar to the RSM background mutation frequency (approximately 10 -5 ) and type (predominantly GC > AT transitions at GL 1 ) of the NciI site). Conversely, an approximately tenfold increase over background mutation frequency was recorded after cell exposure to 20 J/m 2 . In this case, the majority of mutations were C > T transitions preferentially located on the non-transcribed DNA strand at C 1 and C 2 of the NciI site. This mutation spectrum is expected by UV mutagenesis. This is the first evidence of induction of mutations in mitochondrial DNA by treatment of human cells with a carcinogen. (author)

  5. Nuclear mitochondrial DNA activates replication in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Laurent Chatre

    Full Text Available The nuclear genome of eukaryotes is colonized by DNA fragments of mitochondrial origin, called NUMTs. These insertions have been associated with a variety of germ-line diseases in humans. The significance of this uptake of potentially dangerous sequences into the nuclear genome is unclear. Here we provide functional evidence that sequences of mitochondrial origin promote nuclear DNA replication in Saccharomyces cerevisiae. We show that NUMTs are rich in key autonomously replicating sequence (ARS consensus motifs, whose mutation results in the reduction or loss of DNA replication activity. Furthermore, 2D-gel analysis of the mrc1 mutant exposed to hydroxyurea shows that several NUMTs function as late chromosomal origins. We also show that NUMTs located close to or within ARS provide key sequence elements for replication. Thus NUMTs can act as independent origins, when inserted in an appropriate genomic context or affect the efficiency of pre-existing origins. These findings show that migratory mitochondrial DNAs can impact on the replication of the nuclear region they are inserted in.

  6. Adult mitochondrial DNA depletion syndrome with mild manifestations

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    Josef Finsterer

    2013-06-01

    Full Text Available Mitochondrial DNA depletion syndrome (MDS is usually a severe disorder of infancy or childhood, due to a reduced copy number of mtDNA molecules. MDS with only mild, non-specific clinical manifestations and onset in adulthood has not been reported. A 47-year-old Caucasian female with short stature and a history of migraine, endometriosis, Crohn’s disease, C-cell carcinoma of the thyroid gland, and a family history positive for mitochondrial disorder (2 sisters, aunt, niece, developed day-time sleepiness, exercise intolerance, and myalgias in the lower-limb muscles since age 46y. She slept 9-10 hours during the night and 2 hours after lunch daily. Clinical exam revealed sore neck muscles, bilateral ptosis, and reduced Achilles tendon reflexes exclusively. Blood tests revealed hyperlipidemia exclusively. Nerve conduction studies, needle electromyography, and cerebral and spinal magnetic resonance imaging were non-informative. Muscle biopsy revealed detached lobulated fibers with subsarcolemmal accentuation of the NADH and SDH staining. Real-time polymerase chain reaction revealed depletion of the mtDNA down to 9% of normal. MDS may be associated with a mild phenotype in adults and may not significantly progress during the first year after onset. In an adult with hypersomnia, severe tiredness, exercise intolerance, and a family history positive for mitochondrial disorder, a MDS should be considered.

  7. Mitochondrial DNA variation in brood stocks of the lake trout

    International Nuclear Information System (INIS)

    Grewe, P.M.; Hebert, P.D.N.

    1986-01-01

    Efforts are in progress to restore lake trout populations in the Great Lakes from hatchery stocks. In most cases, plantings include a variety of brood stocks that originated from different portions of the Great Lakes. Members of the various stocks can be differentially fin clipped to permit comparison of their survival success, but this does not allow assessment of their reproductive capability in the wild. Assessment of reproductive success requires the existence of genetic markers between brook stocks which will ideally persist over many generations. Efforts to identify allozyme differences between brood stocks have met with little success. The present investigation has employed an alternative technique to identify genetic markers--the restriction analysis of mitochondrial DNA. Mitochondiral DNA analysis of 7 lake trout brood stocks has revealed the existence of 10 mitochondrial clones falling into 3 major groups. The results indicate that mt-DNA markers have great potential for brood stock management. Genetic variability in the nuclear genome of each stock can be maintained by utilizing a large number of male parents, while restricting female parents to members of a single mitochondrial clone. Genetically marked fry could then be produced with only minor shifts in hatchery management

  8. A cryptic mitochondrial DNA link between North European and West African dogs.

    Science.gov (United States)

    Adeola, Adeniyi C; Ommeh, Sheila C; Song, Jiao-Jiao; Olaogun, S Charles; Sanke, Oscar J; Yin, Ting-Ting; Wang, Guo-Dong; Wu, Shi-Fang; Zhou, Zhong-Yin; Lichoti, Jacqueline K; Agwanda, Bernard R; Dawuda, Philip M; Murphy, Robert W; Peng, Min-Sheng; Zhang, Ya-Ping

    2017-03-20

    Domestic dogs have an ancient origin and a long history in Africa. Nevertheless, the timing and sources of their introduction into Africa remain enigmatic. Herein, we analyse variation in mitochondrial DNA (mtDNA) D-loop sequences from 345 Nigerian and 37 Kenyan village dogs plus 1530 published sequences of dogs from other parts of Africa, Europe and West Asia. All Kenyan dogs can be assigned to one of three haplogroups (matrilines; clades): A, B, and C, while Nigerian dogs can be assigned to one of four haplogroups A, B, C, and D. None of the African dogs exhibits a matrilineal contribution from the African wolf (Canis lupus lupaster). The genetic signal of a recent demographic expansion is detected in Nigerian dogs from West Africa. The analyses of mitochondrial genomes reveal a maternal genetic link between modern West African and North European dogs indicated by sub-haplogroup D1 (but not the entire haplogroup D) coalescing around 12,000 years ago. Incorporating molecular anthropological evidence, we propose that sub-haplogroup D1 in West African dogs could be traced back to the late-glacial dispersals, potentially associated with human hunter-gatherer migration from southwestern Europe. Copyright © 2016 Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, and Genetics Society of China. Published by Elsevier Ltd. All rights reserved.

  9. Mitochondrial DNA copy number threshold in mtDNA depletion myopathy.

    Science.gov (United States)

    Durham, S E; Bonilla, E; Samuels, D C; DiMauro, S; Chinnery, P F

    2005-08-09

    The authors measured the absolute amount of mitochondrial DNA (mtDNA) within single muscle fibers from two patients with thymidine kinase 2 (TK2) deficiency and two healthy controls. TK2 deficient fibers containing more than 0.01 mtDNA/microm3 had residual cytochrome c oxidase (COX) activity. This defines the minimum amount of wild-type mtDNA molecules required to maintain COX activity in skeletal muscle and provides an explanation for the mosaic histochemical pattern seen in patients with mtDNA depletion syndrome.

  10. Combining bleach and mild predigestion improves ancient DNA recovery from bones

    DEFF Research Database (Denmark)

    Boessenkool, Sanne; Hanghøj, Kristian Ebbesen; Nistelberger, Heidi M.

    2017-01-01

    library characteristics, such as DNA damage profiles or the composition of microbial communities, are little affected by the pre-extraction protocols. Application of the combined protocol presented in this study will facilitate the genetic analysis of an increasing number of ancient remains...... aimed to improve ancient DNA recovery before library amplification have recently been developed. Here, we test the effects of combining two of such protocols, a bleach wash and a predigestion step, on 12 bone samples of Atlantic cod and domestic horse aged 750-1350 cal. years before present. Using high...

  11. Ancient DNA reveals substantial genetic diversity in the California Condor (Gymnogyps californianus) prior to a population bottleneck

    Science.gov (United States)

    D'Elia, Jesse; Haig, Susan M.; Mullins, Thomas D.; Miller, Mark P.

    2016-01-01

    Critically endangered species that have undergone severe population bottlenecks often have little remaining genetic variation, making it difficult to reconstruct population histories to apply in reintroduction and recovery strategies. By using ancient DNA techniques, it is possible to combine genetic evidence from the historical population with contemporary samples to provide a more complete picture of a species' genetic variation across its historical range and through time. Applying this approach, we examined changes in the mitochondrial DNA (mtDNA) control region (526 base pairs) of the endangered California Condor (Gymnogyps californianus). Results showed a >80% reduction in unique haplotypes over the past 2 centuries. We found no spatial sorting of haplotypes in the historical population; the periphery of the range contained haplotypes that were common throughout the historical range. Direct examination of mtDNA from California Condor museum specimens provided a new window into historical population connectivity and genetic diversity showing: (1) a substantial loss of haplotypes, which is consistent with the hypothesis that condors were relatively abundant in the nineteenth century, but declined rapidly as a result of human-caused mortality; and (2) no evidence of historical population segregation, meaning that the available genetic data offer no cause to avoid releasing condors in unoccupied portions of their historical range.

  12. Primer retention owing to the absence of RNase H1 is catastrophic for mitochondrial DNA replication.

    Science.gov (United States)

    Holmes, J Bradley; Akman, Gokhan; Wood, Stuart R; Sakhuja, Kiran; Cerritelli, Susana M; Moss, Chloe; Bowmaker, Mark R; Jacobs, Howard T; Crouch, Robert J; Holt, Ian J

    2015-07-28

    Encoding ribonuclease H1 (RNase H1) degrades RNA hybridized to DNA, and its function is essential for mitochondrial DNA maintenance in the developing mouse. Here we define the role of RNase H1 in mitochondrial DNA replication. Analysis of replicating mitochondrial DNA in embryonic fibroblasts lacking RNase H1 reveals retention of three primers in the major noncoding region (NCR) and one at the prominent lagging-strand initiation site termed Ori-L. Primer retention does not lead immediately to depletion, as the persistent RNA is fully incorporated in mitochondrial DNA. However, the retained primers present an obstacle to the mitochondrial DNA polymerase γ in subsequent rounds of replication and lead to the catastrophic generation of a double-strand break at the origin when the resulting gapped molecules are copied. Hence, the essential role of RNase H1 in mitochondrial DNA replication is the removal of primers at the origin of replication.

  13. Mitochondrial DNA polymorphisms associated with longevity in a Finnish population.

    Science.gov (United States)

    Niemi, Anna-Kaisa; Hervonen, Antti; Hurme, Mikko; Karhunen, Pekka J; Jylhä, Marja; Majamaa, Kari

    2003-01-01

    Sequence variation in mitochondrial DNA (mtDNA) may cause slight differences both in the functioning of the respiratory chain and in free radical production, and an association between certain mtDNA haplogroups and longevity has been suggested. In order to determine further the role of mtDNA in longevity, we studied the frequencies of mtDNA haplogroups and haplogroup clusters among elderly subjects and controls in a Finnish population. Samples were obtained from 225 persons aged 90-91 years (Vitality 90+) and from 400 middle-aged controls and 257 infants. MtDNA haplogroups were determined by restriction fragment length polymorphism. The haplogroup frequencies of the Vitality 90+ group differed from both those of the middle-aged controls ( P=0.01) and the infants ( P=0.00005), haplogroup H being less frequent than among the middle-aged subjects ( P=0.001) and infants ( P=0.00001), whereas haplogroups U and J were more frequent. Haplogroup clusters also differed between Vitality 90+ and both the middle-aged subjects ( P=0.002) and infants ( P=0.00001), the frequency of haplogroup cluster HV being lower in the former and that of UK and WIX being higher. These data suggest an association between certain mtDNA haplogroups or haplogroup clusters and longevity. Furthermore, our data appear to favour the presence of advantageous polymorphisms and support a role for mitochondria and mtDNA in the degenerative processes involved in ageing.

  14. Introgression of mitochondrial DNA among Myodes voles: consequences for energetics?

    Directory of Open Access Journals (Sweden)

    Boratyński Zbyszek

    2011-12-01

    Full Text Available Abstract Background Introgression of mitochondrial DNA (mtDNA is among the most frequently described cases of reticulate evolution. The tendency of mtDNA to cross interspecific barriers is somewhat counter-intuitive considering the key function of enzymes that it encodes in the oxidative-phosphorylation process, which could give rise to hybrid dysfunction. How mtDNA reticulation affects the evolution of metabolic functions is, however, uncertain. Here we investigated how morpho-physiological traits vary in natural populations of a common rodent (the bank vole, Myodes glareolus and whether this variation could be associated with mtDNA introgression. First, we confirmed that M. glareolus harbour mtDNA introgressed from M. rutilus by analyzing mtDNA (cytochrome b, 954 bp and nuclear DNA (four markers; 2333 bp in total sequence variation and reconstructing loci phylogenies among six natural populations in Finland. We then studied geographic variation in body size and basal metabolic rate (BMR among the populations of M. glareolus and tested its relationship with mtDNA type. Results Myodes glareolus and its arctic neighbour, M. rutilus, are reciprocally monophyletic at the analyzed nuclear DNA loci. In contrast, the two northernmost populations of M. glareolus have a fixed mitotype that is shared with M. rutilus, likely due to introgressive hybridization. The analyses of phenotypic traits revealed that the body mass and whole-body, but not mass corrected, BMR are significantly reduced in M. glareolus females from northern Finland that also have the introgressed mitotype. Restricting the analysis to the single population where the mitotypes coexist, the association of mtDNA type with whole-body BMR remained but those with mass corrected BMR and body mass did not. Mitochondrial sequence variation in the introgressed haplotypes is compatible with demographic growth of the populations, but may also be a result of positive selection. Conclusion Our

  15. Comparison of Suitability of the Most Common Ancient DNA Quantification Methods.

    Science.gov (United States)

    Brzobohatá, Kristýna; Drozdová, Eva; Smutný, Jiří; Zeman, Tomáš; Beňuš, Radoslav

    2017-04-01

    Ancient DNA (aDNA) extracted from historical bones is damaged and fragmented into short segments, present in low quantity, and usually copurified with microbial DNA. A wide range of DNA quantification methods are available. The aim of this study was to compare the five most common DNA quantification methods for aDNA. Quantification methods were tested on DNA extracted from skeletal material originating from an early medieval burial site. The tested methods included ultraviolet (UV) absorbance, real-time quantitative polymerase chain reaction (qPCR) based on SYBR ® green detection, real-time qPCR based on a forensic kit, quantification via fluorescent dyes bonded to DNA, and fragmentary analysis. Differences between groups were tested using a paired t-test. Methods that measure total DNA present in the sample (NanoDrop ™ UV spectrophotometer and Qubit ® fluorometer) showed the highest concentrations. Methods based on real-time qPCR underestimated the quantity of aDNA. The most accurate method of aDNA quantification was fragmentary analysis, which also allows DNA quantification of the desired length and is not affected by PCR inhibitors. Methods based on the quantification of the total amount of DNA in samples are unsuitable for ancient samples as they overestimate the amount of DNA presumably due to the presence of microbial DNA. Real-time qPCR methods give undervalued results due to DNA damage and the presence of PCR inhibitors. DNA quantification methods based on fragment analysis show not only the quantity of DNA but also fragment length.

  16. Two potential Petunia hybrida mitochondrial DNA replication origins show structural and in vitro functional homology with the animal mitochondrial DNA heavy and light strand replication origins

    NARCIS (Netherlands)

    Haas, Jan M. de; Hille, Jacques; Kors, Frank; Meer, Bert van der; Kool, Ad J.; Folkerts, Otto; Nijkamp, H. John J.

    1991-01-01

    Four Petunia hybrida mitochondrial (mt) DNA fragments have been isolated, sequenced, localized on the physical map and analyzed for their ability to initiate specific DNA synthesis. When all four mtDNA fragments were tested as templates in an in vitro DNA synthesizing lysate system, developed from

  17. Mitochondrial nucleoid clusters protect newly synthesized mtDNA during Doxorubicin- and Ethidium Bromide-induced mitochondrial stress

    Energy Technology Data Exchange (ETDEWEB)

    Alán, Lukáš, E-mail: lukas.alan@fgu.cas.cz; Špaček, Tomáš; Pajuelo Reguera, David; Jabůrek, Martin; Ježek, Petr

    2016-07-01

    Mitochondrial DNA (mtDNA) is compacted in ribonucleoprotein complexes called nucleoids, which can divide or move within the mitochondrial network. Mitochondrial nucleoids are able to aggregate into clusters upon reaction with intercalators such as the mtDNA depletion agent Ethidium Bromide (EB) or anticancer drug Doxorobicin (DXR). However, the exact mechanism of nucleoid clusters formation remains unknown. Resolving these processes may help to elucidate the mechanisms of DXR-induced cardiotoxicity. Therefore, we addressed the role of two key nucleoid proteins; mitochondrial transcription factor A (TFAM) and mitochondrial single-stranded binding protein (mtSSB); in the formation of mitochondrial nucleoid clusters during the action of intercalators. We found that both intercalators cause numerous aberrations due to perturbing their native status. By blocking mtDNA replication, both agents also prevented mtDNA association with TFAM, consequently causing nucleoid aggregation into large nucleoid clusters enriched with TFAM, co-existing with the normal nucleoid population. In the later stages of intercalation (> 48 h), TFAM levels were reduced to 25%. In contrast, mtSSB was released from mtDNA and freely distributed within the mitochondrial network. Nucleoid clusters mostly contained nucleoids with newly replicated mtDNA, however the nucleoid population which was not in replication mode remained outside the clusters. Moreover, the nucleoid clusters were enriched with p53, an anti-oncogenic gatekeeper. We suggest that mitochondrial nucleoid clustering is a mechanism for protecting nucleoids with newly replicated DNA against intercalators mediating genotoxic stress. These results provide new insight into the common mitochondrial response to mtDNA stress and can be implied also on DXR-induced mitochondrial cytotoxicity. - Highlights: • The mechanism for mitochondrial nucleoid clustering is proposed. • DNA intercalators (Doxorubicin or Ethidium Bromide) prevent TFAM

  18. The Pacific Rat Race to Easter Island: Tracking the Prehistoric Dispersal of Rattus exulans Using Ancient Mitochondrial Genomes

    Directory of Open Access Journals (Sweden)

    Katrina West

    2017-05-01

    Full Text Available The location of the immediate eastern Polynesian origin for the settlement of Easter Island (Rapa Nui, remains unclear with conflicting archeological and linguistic evidence. Previous genetic commensal research using the Pacific rat, Rattus exulans; a species transported by humans across Remote Oceania and throughout the Polynesian Triangle, has identified broad interaction spheres across the region. However, there has been limited success in distinguishing finer-scale movements between Remote Oceanic islands as the same mitochondrial control region haplotype has been identified in the majority of ancient rat specimens. To improve molecular resolution and identify a pattern of prehistoric dispersal to Easter Island, we sequenced complete mitochondrial genomes from ancient Pacific rat specimens obtained from early archeological contexts across West and East Polynesia. Ancient Polynesian rat haplotypes are closely related and reflect the widely supported scenario of a central East Polynesian homeland region from which eastern expansion occurred. An Easter Island and Tubuai (Austral Islands grouping of related haplotypes suggests that both islands were established by the same colonization wave, proposed to have originated in the central homeland region before dispersing through the south-eastern corridor of East Polynesia.

  19. Cellular aging of mitochondrial DNA-depleted cells

    International Nuclear Information System (INIS)

    Park, Sun Young; Choi, Bongkun; Cheon, Hwanju; Pak, Youngmi Kim; Kulawiec, Mariola; Singh, Keshav K.; Lee, Myung-Shik

    2004-01-01

    We have reported that mitochondrial DNA-depleted ρ 0 cells are resistant to cell death. Because aged cells have frequent mitochondrial DNA mutations, the resistance of ρ 0 cells against cell death might be related to the apoptosis resistance of aged cells and frequent development of cancers in aged individuals. We studied if ρ 0 cells have features simulating aged cells. SK-Hep1 hepatoma ρ 0 cells showed typical morphology associated with aging such as increased size and elongated appearance. They had increased senescence-associated β-Gal activity, lipofuscin pigment, and plasminogen activator inhibitor-1 expression. Consistent with their decreased proliferation, the expression of mitotic cyclins was decreased and that of cdk inhibitors was increased. Rb hypophosphorylation and decreased telomerase activity were also noted. Features simulating aged cells were also observed in MDA-MB-435 ρ 0 cells. These results support the mitochondrial theory of aging, and suggest that ρ 0 cells could serve as an in vitro model for aged cells

  20. Mitochondrial DNA phylogeography of least cisco Coregonus sardinella in Alaska.

    Science.gov (United States)

    Padula, V M; Causey, D; López, J A

    2017-03-01

    This study presents the first detailed analysis of the mitochondrial DNA diversity of least cisco Coregonus sardinella in Alaska using a 678 bp segment of the control region (D-loop) of the mitochondrial genome. Findings suggest that the history of C. sardinella in Alaska differs from that of other species of Coregonus present in the state and surrounding regions. The examined populations of C. sardinella are genetically diverse across Alaska. Sixty-eight distinct mitochondrial haplotypes were identified among 305 individuals sampled from nine locations. The haplotype minimum spanning network and phylogeny showed a modest level of geographic segregation among haplotypes, suggesting high levels of on-going or recent connectivity among distant populations. Observed Φ ST values and the results of homogeneity and AMOVAs indicate incipient genetic differentiation between aggregations in three broad regional groups. Sites north of the Brooks Range formed one group, sites in the Yukon and Selawik Rivers formed a second group and sites south of the Yukon drainage formed the third group. Overall, the sequence data showed that a large proportion of mtDNA genetic variation in C. sardinella is shared across Alaska, but this variation is not homogeneously distributed across all regions and for all haplotype groups. © 2017 The Fisheries Society of the British Isles.

  1. Discovery of cyanophage genomes which contain mitochondrial DNA polymerase.

    Science.gov (United States)

    Chan, Yi-Wah; Mohr, Remus; Millard, Andrew D; Holmes, Antony B; Larkum, Anthony W; Whitworth, Anna L; Mann, Nicholas H; Scanlan, David J; Hess, Wolfgang R; Clokie, Martha R J

    2011-08-01

    DNA polymerase γ is a family A DNA polymerase responsible for the replication of mitochondrial DNA in eukaryotes. The origins of DNA polymerase γ have remained elusive because it is not present in any known bacterium, though it has been hypothesized that mitochondria may have inherited the enzyme by phage-mediated nonorthologous displacement. Here, we present an analysis of two full-length homologues of this gene, which were found in the genomes of two bacteriophages, which infect the chlorophyll-d containing cyanobacterium Acaryochloris marina. Phylogenetic analyses of these phage DNA polymerase γ proteins show that they branch deeply within the DNA polymerase γ clade and therefore share a common origin with their eukaryotic homologues. We also found homologues of these phage polymerases in the environmental Community Cyberinfrastructure for Advanced Microbial Ecology Research and Analysis (CAMERA) database, which fell in the same clade. An analysis of the CAMERA assemblies containing the environmental homologues together with the filter fraction metadata indicated some of these assemblies may be of bacterial origin. We also show that the phage-encoded DNA polymerase γ is highly transcribed as the phage genomes are replicated. These findings provide data that may assist in reconstructing the evolution of mitochondria.

  2. Forensics and mitochondrial DNA: applications, debates, and foundations.

    Science.gov (United States)

    Budowle, Bruce; Allard, Marc W; Wilson, Mark R; Chakraborty, Ranajit

    2003-01-01

    Debate on the validity and reliability of scientific methods often arises in the courtroom. When the government (i.e., the prosecution) is the proponent of evidence, the defense is obliged to challenge its admissibility. Regardless, those who seek to use DNA typing methodologies to analyze forensic biological evidence have a responsibility to understand the technology and its applications so a proper foundation(s) for its use can be laid. Mitochondrial DNA (mtDNA), an extranuclear genome, has certain features that make it desirable for forensics, namely, high copy number, lack of recombination, and matrilineal inheritance. mtDNA typing has become routine in forensic biology and is used to analyze old bones, teeth, hair shafts, and other biological samples where nuclear DNA content is low. To evaluate results obtained by sequencing the two hypervariable regions of the control region of the human mtDNA genome, one must consider the genetically related issues of nomenclature, reference population databases, heteroplasmy, paternal leakage, recombination, and, of course, interpretation of results. We describe the approaches, the impact some issues may have on interpretation of mtDNA analyses, and some issues raised in the courtroom.

  3. Ancient pathogen DNA in human teeth and petrous bones

    DEFF Research Database (Denmark)

    Margaryan, Ashot; Hansen, Henrik B.; Rasmussen, Simon

    2018-01-01

    pestis. Based on shotgun sequencing data, four of these five plague victims showed clearly detectable levels of Y.pestis DNA in the teeth, whereas all the petrous bones failed to produce Y.pestis DNA above baseline levels. A broader comparative metagenomic analysis of teeth and petrous bones from 10...

  4. Ancient DNA investigations: A review on their significance in ...

    African Journals Online (AJOL)

    However, its degradation and post-mortem chemical alteration make difficult its quantification and amplification. Moreover the study of aDNA is challenging due to the contamination by exogenous current DNA. Recently, the progress of molecular techniques and the use of sophisticated approaches greatly improved the ratio ...

  5. Quantification and presence of human ancient DNA in burial place ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... burial place remains of Turkey using real time ... DNA was isolaled from fossil bone tissue remains with Bio Robot EZ1 and ... the increase in the amount of DNA as it is amplified. The ... species or human blood in this work.

  6. DNA in ancient bone - where is it located and how should we extract it?

    DEFF Research Database (Denmark)

    Campos, Paula; Craig, Oliver E.; Turner-Walker, Gordon

    2012-01-01

    Despite the widespread use of bones in ancient DNA (aDNA) studies, relatively little concrete information exists in regard to how the DNA in mineralised collagen degrades, or where it survives in the material's architecture. While, at the macrostructural level, physical exclusion of microbes...... and other external contaminants may be an important feature, and, at the ultrastructural level, the adsorption of DNA to hydroxyapatite and/or binding of DNA to Type I collagen may stabilise the DNA, the relative contribution of each, and what other factors may be relevant, are unclear....... The question arises as to whether this may be due to post-collection preservation or just an artefact of the extraction methods used in these different studies? In an attempt to resolve these questions, we examine the efficacy of DNA extraction methods, and the quality and quantity of DNA recovered from both...

  7. Exploring the mitochondrial DNA variability of the Amazonian Yanomami.

    Science.gov (United States)

    Varano, Sara; Scorrano, Gabriele; Martínez-Labarga, Cristina; Finocchio, Andrea; Rapone, Cesare; Berti, Andrea; Rickards, Olga

    2016-11-01

    The aim of this study was to explore the mitochondrial variability in the Yanomami population to reconstruct its demographic history and explore its genetic composition in relation to its cultural and linguistic features. A total of 174 human head hair shafts -collected in 1958- belonging to individuals from a Yanomami group living in Santa Isabel, Brazil, were analyzed. Automated extraction of the hairs was performed, and several methods were applied to optimize the analysis of the degraded DNA. The mtDNA hypervariable segments I-II, along with the 9-bp COII-tRNA Lys deletion, were investigated. Using published data from the Yanomami and other Amazonian populations, several statistical analyses were carried out to explore the genetic variability within the study population. Ninety eight percent of the mitochondrial DNA (mtDNA) sequences analyzed belonged to Native American haplogroups, while 2% belonged to African haplogroups. Compared with the Yanomami groups previously studied, the Santa Isabel sample seemed more genetically similar to other Amazonian populations. Among the Yanomami samples studied to date, the Santa Isabel Yanomami show a higher genetic heterogeneity. This could be due to gene flow with non-Yanomami populations, as well as to the introduction of new mitochondrial haplotypes by gold miners. In both cases, the geographic location of Santa Isabel might have made this Yanomami village less isolated than the others, suggesting that the Rio Negro played a central role in increasing its genetic variability. On the whole, the Yanomami were quite genetically diversified, probably mirroring their great linguistic heterogeneity. Am. J. Hum. Biol. 28:846-856, 2016. © 2016Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. Continued colonization of the human genome by mitochondrial DNA.

    Directory of Open Access Journals (Sweden)

    Miria Ricchetti

    2004-09-01

    Full Text Available Integration of mitochondrial DNA fragments into nuclear chromosomes (giving rise to nuclear DNA sequences of mitochondrial origin, or NUMTs is an ongoing process that shapes nuclear genomes. In yeast this process depends on double-strand-break repair. Since NUMTs lack amplification and specific integration mechanisms, they represent the prototype of exogenous insertions in the nucleus. From sequence analysis of the genome of Homo sapiens, followed by sampling humans from different ethnic backgrounds, and chimpanzees, we have identified 27 NUMTs that are specific to humans and must have colonized human chromosomes in the last 4-6 million years. Thus, we measured the fixation rate of NUMTs in the human genome. Six such NUMTs show insertion polymorphism and provide a useful set of DNA markers for human population genetics. We also found that during recent human evolution, Chromosomes 18 and Y have been more susceptible to colonization by NUMTs. Surprisingly, 23 out of 27 human-specific NUMTs are inserted in known or predicted genes, mainly in introns. Some individuals carry a NUMT insertion in a tumor-suppressor gene and in a putative angiogenesis inhibitor. Therefore in humans, but not in yeast, NUMT integrations preferentially target coding or regulatory sequences. This is indeed the case for novel insertions associated with human diseases and those driven by environmental insults. We thus propose a mutagenic phenomenon that may be responsible for a variety of genetic diseases in humans and suggest that genetic or environmental factors that increase the frequency of chromosome breaks provide the impetus for the continued colonization of the human genome by mitochondrial DNA.

  9. Mitochondrial and Nuclear DNA in Patients with Severe Polytrauma

    Directory of Open Access Journals (Sweden)

    M. Sh Khubutia

    2013-01-01

    Full Text Available The components of mitochondria from the cells damaged by injury are a key component for the development of systemic inflammatory response syndrome (SIRS under aseptic conditions. At the same time, there is a significant increase in the plasma level of mitochondrial DNA (mtDNA, which may be a prognostic marker for infectious complications in patients with severe polytrauma. Objective: to study the time course of changes in the serum levels of mtDNA and nuclear DNA (nDNA in healthy individuals and patients with polytrauma and to reveal its possible association with the development of infectious pulmonary complications and with mortality. Subjects and methods. Seven healthy volunteers and 25 polytrauma with polytrauma of a mean injury severity score (ISS of 40.2±9.2. Sixteen (64% patients developed purulent tracheobronchitis and pneumonia; 5 (20% patients died. The amount of mtDNA and nDNA was determined within the first at 12 and 24 hours, then on days 3 and 5—7 after injury by the authors’ modified procedure using as the exogenous control of a circular DNA molecule. The content of mtDNA and nDNA was expressed as absolute values, by taking the arithmetic mean values as 100% for the volunteers. Results. There was a more than 2.5-fold increase in mtDNA levels in dead patients as compared to survivors (p<0.05; the differences in nDMA levels were insignificant (p=0.1. Within the first 12 hours, the mean mtDNA level in patients with pneumonia was 34 times greater than the reference values and continued to rise in the following 12 hours whereas in those without pneumonia, it was only 17 times higher with its further decrease in the comparable time periods. In the first 12 hours, nDNA was increased in both groups, but 24 hours after injury it was 2555 times more than the reference value only in patients with pneumonia whereas it was decreased 3-fold in those without this condition. Conclusion. This paper is the first to describe the time course of

  10. Ancient DNA Analysis Suggests Negligible Impact of the Wari Empire Expansion in Peru's Central Coast during the Middle Horizon.

    Science.gov (United States)

    Valverde, Guido; Barreto Romero, María Inés; Flores Espinoza, Isabel; Cooper, Alan; Fehren-Schmitz, Lars; Llamas, Bastien; Haak, Wolfgang

    2016-01-01

    The analysis of ancient human DNA from South America allows the exploration of pre-Columbian population history through time and to directly test hypotheses about cultural and demographic evolution. The Middle Horizon (650-1100 AD) represents a major transitional period in the Central Andes, which is associated with the development and expansion of ancient Andean empires such as Wari and Tiwanaku. These empires facilitated a series of interregional interactions and socio-political changes, which likely played an important role in shaping the region's demographic and cultural profiles. We analyzed individuals from three successive pre-Columbian cultures present at the Huaca Pucllana archaeological site in Lima, Peru: Lima (Early Intermediate Period, 500-700 AD), Wari (Middle Horizon, 800-1000 AD) and Ychsma (Late Intermediate Period, 1000-1450 AD). We sequenced 34 complete mitochondrial genomes to investigate the potential genetic impact of the Wari Empire in the Central Coast of Peru. The results indicate that genetic diversity shifted only slightly through time, ruling out a complete population discontinuity or replacement driven by the Wari imperialist hegemony, at least in the region around present-day Lima. However, we caution that the very subtle genetic contribution of Wari imperialism at the particular Huaca Pucllana archaeological site might not be representative for the entire Wari territory in the Peruvian Central Coast.

  11. Ancient DNA Analysis Suggests Negligible Impact of the Wari Empire Expansion in Peru's Central Coast during the Middle Horizon.

    Directory of Open Access Journals (Sweden)

    Guido Valverde

    Full Text Available The analysis of ancient human DNA from South America allows the exploration of pre-Columbian population history through time and to directly test hypotheses about cultural and demographic evolution. The Middle Horizon (650-1100 AD represents a major transitional period in the Central Andes, which is associated with the development and expansion of ancient Andean empires such as Wari and Tiwanaku. These empires facilitated a series of interregional interactions and socio-political changes, which likely played an important role in shaping the region's demographic and cultural profiles. We analyzed individuals from three successive pre-Columbian cultures present at the Huaca Pucllana archaeological site in Lima, Peru: Lima (Early Intermediate Period, 500-700 AD, Wari (Middle Horizon, 800-1000 AD and Ychsma (Late Intermediate Period, 1000-1450 AD. We sequenced 34 complete mitochondrial genomes to investigate the potential genetic impact of the Wari Empire in the Central Coast of Peru. The results indicate that genetic diversity shifted only slightly through time, ruling out a complete population discontinuity or replacement driven by the Wari imperialist hegemony, at least in the region around present-day Lima. However, we caution that the very subtle genetic contribution of Wari imperialism at the particular Huaca Pucllana archaeological site might not be representative for the entire Wari territory in the Peruvian Central Coast.

  12. Ancient DNA analysis of the oldest canid species from the Siberian Arctic and genetic contribution to the domestic dog.

    Directory of Open Access Journals (Sweden)

    Esther J Lee

    Full Text Available Modern Arctic Siberia provides a wealth of resources for archaeological, geological, and paleontological research to investigate the population dynamics of faunal communities from the Pleistocene, particularly as the faunal material coming from permafrost has proven suitable for genetic studies. In order to examine the history of the Canid species in the Siberian Arctic, we carried out genetic analysis of fourteen canid remains from various sites, including the well-documented Upper Paleolithic Yana RHS and Early Holocene Zhokhov Island sites. Estimated age of samples range from as recent as 1,700 years before present (YBP to at least 360,000 YBP for the remains of the extinct wolf, Canis cf. variabilis. In order to examine the genetic affinities of ancient Siberian canids species to the domestic dog and modern wolves, we obtained mitochondrial DNA control region sequences and compared them to published ancient and modern canid sequences. The older canid specimens illustrate affinities with pre-domestic dog/wolf lineages while others appear in the major phylogenetic clades of domestic dogs. Our results suggest a European origin of domestic dog may not be conclusive and illustrates an emerging complexity of genetic contribution of regional wolf breeds to the modern Canis gene pool.

  13. Fungal palaeodiversity revealed using high-throughput metabarcoding of ancient DNA from arctic permafrost

    DEFF Research Database (Denmark)

    Bellemain, Eva; Davey, Marie L.; Kauserud, Håvard

    2013-01-01

    The taxonomic and ecological diversity of ancient fungal communities was assessed by combining next generation sequencing and metabarcoding of DNA preserved in permafrost. Twenty-six sediment samples dated 16000-32000 radiocarbon years old from two localities in Siberia were analysed for fungal ITS...

  14. Ancient DNA: Saber-Toothed Cats Are the Same Beasts After All.

    Science.gov (United States)

    Meachen, Julie A

    2017-11-06

    Ancient DNA from the saber-toothed cat Homotherium reveals that the late Pleistocene species from Europe and North America were the same. Homotherium turns out to be only distantly related to the well-known saber-toothed Smilodon. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Mitochondrial DNA Depletion Syndrome is Expressed in Amniotic Fluid Cell Cultures

    OpenAIRE

    Blake, Julian C.; Taanman, Jan-Willem; Morris, Andrew M. M.; Gray, R. George F.; Cooper, J. Mark; McKiernan, Patrick J.; Leonard, James V.; Schapira, Anthony H. V.

    1999-01-01

    Mitochondrial DNA depletion syndrome is an autosomal inherited disease associated with grossly reduced cellular levels of mitochondrial DNA in infancy. Most patients are born after a full and uncomplicated pregnancy, are normal at birth, but develop symptoms in the early neonatal period. These observations have led to the suggestion that the patients have a defect affecting the control of mitochondrial DNA copy number after birth. Using immunocytochemical techniques, we demonstrated that the ...

  16. Pros and cons of methylation-based enrichment methods for ancient DNA

    Science.gov (United States)

    Seguin-Orlando, Andaine; Gamba, Cristina; Sarkissian, Clio Der; Ermini, Luca; Louvel, Guillaume; Boulygina, Eugenia; Sokolov, Alexey; Nedoluzhko, Artem; Lorenzen, Eline D.; Lopez, Patricio; McDonald, H. Gregory; Scott, Eric; Tikhonov, Alexei; Stafford,, Thomas W.; Alfarhan, Ahmed H.; Alquraishi, Saleh A.; Al-Rasheid, Khaled A. S.; Shapiro, Beth; Willerslev, Eske; Prokhortchouk, Egor; Orlando, Ludovic

    2015-01-01

    The recent discovery that DNA methylation survives in fossil material provides an opportunity for novel molecular approaches in palaeogenomics. Here, we apply to ancient DNA extracts the probe-independent Methylated Binding Domains (MBD)-based enrichment method, which targets DNA molecules containing methylated CpGs. Using remains of a Palaeo-Eskimo Saqqaq individual, woolly mammoths, polar bears and two equine species, we confirm that DNA methylation survives in a variety of tissues, environmental contexts and over a large temporal range (4,000 to over 45,000 years before present). MBD enrichment, however, appears principally biased towards the recovery of CpG-rich and long DNA templates and is limited by the fast post-mortem cytosine deamination rates of methylated epialleles. This method, thus, appears only appropriate for the analysis of ancient methylomes from very well preserved samples, where both DNA fragmentation and deamination have been limited. This work represents an essential step toward the characterization of ancient methylation signatures, which will help understanding the role of epigenetic changes in past environmental and cultural transitions. PMID:26134828

  17. Historically low mitochondrial DNA diversity in koalas (Phascolarctos cinereus

    Directory of Open Access Journals (Sweden)

    Tsangaras Kyriakos

    2012-10-01

    Full Text Available Abstract Background The koala (Phascolarctos cinereus is an arboreal marsupial that was historically widespread across eastern Australia until the end of the 19th century when it suffered a steep population decline. Hunting for the fur trade, habitat conversion, and disease contributed to a precipitous reduction in koala population size during the late 1800s and early 1900s. To examine the effects of these reductions in population size on koala genetic diversity, we sequenced part of the hypervariable region of mitochondrial DNA (mtDNA in koala museum specimens collected in the 19th and 20th centuries, hypothesizing that the historical samples would exhibit greater genetic diversity. Results The mtDNA haplotypes present in historical museum samples were identical to haplotypes found in modern koala populations, and no novel haplotypes were detected. Rarefaction analyses suggested that the mtDNA genetic diversity present in the museum samples was similar to that of modern koalas. Conclusions Low mtDNA diversity may have been present in koala populations prior to recent population declines. When considering management strategies, low genetic diversity of the mtDNA hypervariable region may not indicate recent inbreeding or founder events but may reflect an older historical pattern for koalas.

  18. Historically low mitochondrial DNA diversity in koalas (Phascolarctos cinereus).

    Science.gov (United States)

    Tsangaras, Kyriakos; Ávila-Arcos, María C; Ishida, Yasuko; Helgen, Kristofer M; Roca, Alfred L; Greenwood, Alex D

    2012-10-24

    The koala (Phascolarctos cinereus) is an arboreal marsupial that was historically widespread across eastern Australia until the end of the 19th century when it suffered a steep population decline. Hunting for the fur trade, habitat conversion, and disease contributed to a precipitous reduction in koala population size during the late 1800s and early 1900s. To examine the effects of these reductions in population size on koala genetic diversity, we sequenced part of the hypervariable region of mitochondrial DNA (mtDNA) in koala museum specimens collected in the 19th and 20th centuries, hypothesizing that the historical samples would exhibit greater genetic diversity. The mtDNA haplotypes present in historical museum samples were identical to haplotypes found in modern koala populations, and no novel haplotypes were detected. Rarefaction analyses suggested that the mtDNA genetic diversity present in the museum samples was similar to that of modern koalas. Low mtDNA diversity may have been present in koala populations prior to recent population declines. When considering management strategies, low genetic diversity of the mtDNA hypervariable region may not indicate recent inbreeding or founder events but may reflect an older historical pattern for koalas.

  19. Development of a Model for the Teaching of Mitochondrial DNA

    Directory of Open Access Journals (Sweden)

    A.P.S. Souza

    2010-05-01

    Full Text Available The Cellular Biology and Molecular Biology are fields of Science that use very abstract concepts, because they look into microscopic and molecular aspects of the nature. The process of teaching/learning of those disciplines requires didactic material, as an alternative approach for the students, to increase the chances of understanding these issues and to become an important tool in the synthesis of this knowledge. One of the methods that can be employed is the didactic models based on multimedia, because they allow an easy and fun interaction with these subjects. On this work was created a new educational model that represents the human mitochondrial DNA molecule, mtDNA, in its circular form, using the softwares Excel 2007 and PowerPoint 2007. The model was constructed in hypertext format, which allowed a quick and interactive access to the information contained in the genes found in the L and the H strands of mtDNA, and its function in the mitochondrial processes, like themechanism of energy production that occurs inside of the mitochondria by the coupling of electron transfer and ATP synthesis or still others uses like forensic identification.

  20. A new model for ancient DNA decay based on paleogenomic meta-analysis.

    Science.gov (United States)

    Kistler, Logan; Ware, Roselyn; Smith, Oliver; Collins, Matthew; Allaby, Robin G

    2017-06-20

    The persistence of DNA over archaeological and paleontological timescales in diverse environments has led to a revolutionary body of paleogenomic research, yet the dynamics of DNA degradation are still poorly understood. We analyzed 185 paleogenomic datasets and compared DNA survival with environmental variables and sample ages. We find cytosine deamination follows a conventional thermal age model, but we find no correlation between DNA fragmentation and sample age over the timespans analyzed, even when controlling for environmental variables. We propose a model for ancient DNA decay wherein fragmentation rapidly reaches a threshold, then subsequently slows. The observed loss of DNA over time may be due to a bulk diffusion process in many cases, highlighting the importance of tissues and environments creating effectively closed systems for DNA preservation. This model of DNA degradation is largely based on mammal bone samples due to published genomic dataset availability. Continued refinement to the model to reflect diverse biological systems and tissue types will further improve our understanding of ancient DNA breakdown dynamics. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  1. Additional mitochondrial DNA influences the interactions between the nuclear and mitochondrial genomes in a bovine embryo model of nuclear transfer.

    Science.gov (United States)

    Srirattana, Kanokwan; St John, Justin C

    2018-05-08

    We generated cattle embryos using mitochondrial supplementation and somatic cell nuclear transfer (SCNT), named miNT, to determine how additional mitochondrial DNA (mtDNA) modulates the nuclear genome. To eliminate any confounding effects from somatic cell mtDNA in intraspecies SCNT, donor cell mtDNA was depleted prior to embryo production. Additional oocyte mtDNA did not affect embryo development rates but increased mtDNA copy number in blastocyst stage embryos. Moreover, miNT-derived blastocysts had different gene expression profiles when compared with SCNT-derived blastocysts. Additional mtDNA increased expression levels of genes involved in oxidative phosphorylation, cell cycle and DNA repair. Supplementing the embryo culture media with a histone deacetylase inhibitor, Trichostatin A (TSA), had no beneficial effects on the development of miNT-derived embryos, unlike SCNT-derived embryos. When compared with SCNT-derived blastocysts cultured in the presence of TSA, additional mtDNA alone had beneficial effects as the activity of glycolysis may increase and embryonic cell death may decrease. However, these beneficial effects were not found with additional mtDNA and TSA together, suggesting that additional mtDNA alone enhances reprogramming. In conclusion, additional mtDNA increased mtDNA copy number and expression levels of genes involved in energy production and embryo development in blastocyst stage embryos emphasising the importance of nuclear-mitochondrial interactions.

  2. Mitochondrial DNA in wildlife forensic science: Species identification of tissues

    Science.gov (United States)

    Cronin, Matthew A.; Palmisciano, Daniel A.; Vyse, Ernest R.; Cameron, David G.

    1991-01-01

    A common problem in wildlife law enforcement is identifying the species of origin of carcasses, meat, or blood when morphological characters such as hair or bones are not available. Immunological and protein electrophoretic (allozyme or general protein) procedures have been used in species identification with considerable success (Bunch et al. 1976, McClymont et al. 1982, Wolfe 1983, Mardini 1984, Pex and Wolfe 1985, Dratch 1986), However, immunological tests often are not sensitive enough to distinguish closely related species. Furthermore, electrophoretically detectable protein polymorphisms may be lacking in certain populations or species and may not be species-specific.Analysis of DNA in human and wildlife forensics has been shown to be a potentially powerful tool for identification of individuals (Jeffreys et al. 1985, Vassartet al. 1987, Thommasen et al. 1989). Differences in copy number and nucleotide sequence of repetitive sequences in the nuclear (chromosomal) DNA result in hypervariability and individual-specific patterns which have been termed DNA "fingerprints." However, these patterns may be too variable for species identification necessitating analyses of more conservative parts of the genome.Mitochondrial DNA (mtDNA) is haploid, maternally inherited, similar in nucleotide sequence among conspecifics from the same geographic region, and more suitable for species identification, in contrast to hypervariable DNA fingerprints. MtDNA has several characteristics which make it useful as a species-specific marker. In mammals, individuals have a single mtDNA genotype shared by all tissues. Because mtDNA is haploid and reflects only maternal ancestry, the mtDNA gene number in a population is 4 times less than the nuclear gene number (Birky et al. 1983). This can result in relatively rapid loss or fixation of mtDNA genotypes so that all individuals in a population may be descended from a single ancestral female in as few as 4N (N = population size) generations

  3. Parasitic infections and resource economy of Danish Iron Age settlement through ancient DNA sequencing.

    Science.gov (United States)

    Tams, Katrine Wegener; Jensen Søe, Martin; Merkyte, Inga; Valeur Seersholm, Frederik; Henriksen, Peter Steen; Klingenberg, Susanne; Willerslev, Eske; Kjær, Kurt H; Hansen, Anders Johannes; Kapel, Christian Moliin Outzen

    2018-01-01

    In this study, we screen archaeological soil samples by microscopy and analyse the samples by next generation sequencing to obtain results with parasites at species level and untargeted findings of plant and animal DNA. Three separate sediment layers of an ancient man-made pond in Hoby, Denmark, ranging from 100 BC to 200 AD, were analysed by microscopy for presence of intestinal worm eggs and DNA analysis were performed to identify intestinal worms and dietary components. Ancient DNA of parasites, domestic animals and edible plants revealed a change in use of the pond over time reflecting the household practice in the adjacent Iron Age settlement. The most abundant parasite found belonged to the Ascaris genus, which was not possible to type at species level. For all sediment layers the presence of eggs of the human whipworm Trichuris trichiura and the beef tapeworm Taenia saginata suggests continuous disposal of human faeces in the pond. Moreover, the continuous findings of T. saginata further imply beef consumption and may suggest that cattle were living in the immediate surrounding of the site throughout the period. Findings of additional host-specific parasites suggest fluctuating presence of other domestic animals over time: Trichuris suis (pig), Parascaris univalens (horse), Taenia hydatigena (dog and sheep). Likewise, alternating occurrence of aDNA of edible plants may suggest changes in agricultural practices. Moreover, the composition of aDNA of parasites, plants and vertebrates suggests a significant change in the use of the ancient pond over a period of three centuries.

  4. Prolonged decay of molecular rate estimates for metazoan mitochondrial DNA

    Directory of Open Access Journals (Sweden)

    Martyna Molak

    2015-03-01

    Full Text Available Evolutionary timescales can be estimated from genetic data using the molecular clock, often calibrated by fossil or geological evidence. However, estimates of molecular rates in mitochondrial DNA appear to scale negatively with the age of the clock calibration. Although such a pattern has been observed in a limited range of data sets, it has not been studied on a large scale in metazoans. In addition, there is uncertainty over the temporal extent of the time-dependent pattern in rate estimates. Here we present a meta-analysis of 239 rate estimates from metazoans, representing a range of timescales and taxonomic groups. We found evidence of time-dependent rates in both coding and non-coding mitochondrial markers, in every group of animals that we studied. The negative relationship between the estimated rate and time persisted across a much wider range of calibration times than previously suggested. This indicates that, over long time frames, purifying selection gives way to mutational saturation as the main driver of time-dependent biases in rate estimates. The results of our study stress the importance of accounting for time-dependent biases in estimating mitochondrial rates regardless of the timescale over which they are inferred.

  5. Signatures of Climatic Change In Human Mitochondrial Dna From Europe

    Science.gov (United States)

    Richards, M. B.; Macaulay, V. A.; Torroni, A.; Bandelt, H.-J.

    Founder analysis is an approach to analysing non-recombining DNA sequence data, such as variation in the mitochondrial DNA (mtDNA), which aims at identifying and dating migrations into new territory. We applied the approach to about 4,000 human mtDNA sequences from Europe and the Near East, in order to estimate the proportion of modern lineages whose ancestors arrived at various times during the continent's past. We found that the major signal dates to about 15,000 years ago, at the time of rewarming following the Last Glacial Maximum (LGM). There is little or no archaeological evidence for immigration into Europe at this time, and the record indicates that at least parts of southern Europe remained populated during the LGM. Therefore, we interpret this signal as the trace of a bottleneck at the time of the LGM, as a result of the retreat from northern Europe during the peak of the glaciation, followed by a re-expansion from one or more refugial zones. Immigration episodes then figure at the beginning of the Early Upper Palaeolithic, during the Middle Upper Palaeolithic, and with the Neolithic. The impact of the latter on the composition of the European mtDNA pool was evidently rather minor. This result implies that climate is likely to have been a major force shaping human demographic history in Europe.

  6. Is the ancient permafrost bacteria able to keep DNA stable?

    Indian Academy of Sciences (India)

    lated strains was extracted by using a Fast DNA kit for soil (BIO 101, Vista, USA) based .... lites, but its movement is extremely slow (Burt and Williams. 1976). A bacterium of ... Despite the nature of mutations, we think the degree of variability in ...

  7. What cost mitochondria? The maintenance of functional mitochondrial DNA within and across generations

    NARCIS (Netherlands)

    Aanen, D.K.; Spelbrink, J.N.; Beekman, M.

    2014-01-01

    The peculiar biology of mitochondrial DNA (mtDNA) potentially has detrimental consequences for organismal health and lifespan. Typically, eukaryotic cells contain multiple mitochondria, each with multiple mtDNA genomes. The high copy number of mtDNA implies that selection on mtDNA functionality is

  8. Tracking down human contamination in ancient human teeth

    DEFF Research Database (Denmark)

    Sampietro, María Lourdes; Gilbert, M Thomas P; Lao, Oscar

    2006-01-01

    DNA sequences can be used to support data authenticity is misleading in scenarios where the presence of old contaminant sequences is possible. We argue therefore that the typing of those involved in the manipulation of the ancient human specimens is critical in order to ensure that generated results......DNA contamination arising from the manipulation of ancient calcified tissue samples is a poorly understood, yet fundamental, problem that affects the reliability of ancient DNA (aDNA) studies. We have typed the mitochondrial DNA hypervariable region I of the only 6 people involved in the excavation...

  9. Mitochondrial DNA analysis of two southern African elephant populations

    Directory of Open Access Journals (Sweden)

    M.F. Essop

    1996-08-01

    Full Text Available The modern view is that there are at most only two valid forms of the African elephant namely Loxodonta qfricana africana, the bush elephant, and L.a. cyclotis, the forest elephant (Ansell 1974; Meester et al. 1986. The Knysna elephant which was also described as a separate sub-species is now almost extinct. Plans to augment the remnant population by introducing other animals must take into account the taxonomic questions and issue of conserving elephant gene pools (Greig 1982a. Mitochondrial DNA (mtDNA restriction fragment-size comparisons were performed on specimens from the Kruger National Park and the Addo Elephant National Park. If the Addo population's results are extrapolated to the Knysna population, it may be concluded that there is no genetic evidence for the Kruger and Knysna elephant populations to be considered as different sub-species.

  10. Oxidants and not alkylating agents induce rapid mtDNA loss and mitochondrial dysfunction

    Science.gov (United States)

    Furda, Amy M.; Marrangoni, Adele M.; Lokshin, Anna; Van Houten, Bennett

    2013-01-01

    Mitochondrial DNA (mtDNA) is essential for proper mitochondrial function and encodes 22 tRNAs, 2 rRNAs and 13 polypeptides that make up subunits of complex I, III, IV, in the electron transport chain and complex V, the ATP synthase. Although mitochondrial dysfunction has been implicated in processes such as premature aging, neurodegeneration, and cancer, it has not been shown whether persistent mtDNA damage causes a loss of oxidative phosphorylation. We addressed this question by treating mouse embryonic fibroblasts with either hydrogen peroxide (H2O2) or the alkylating agent methyl methanesulfonate (MMS) and measuring several endpoints, including mtDNA damage and repair rates using QPCR, levels of mitochondrial- and nuclear-encoded proteins using antibody analysis, and a pharmacologic profile of mitochondria using the Seahorse Extracellular Flux Analyzer. We show that a 60 min treatment with H2O2 causes persistent mtDNA lesions, mtDNA loss, decreased levels of a nuclear-encoded mitochondrial subunit, a loss of ATP-linked oxidative phosphorylation and a loss of total reserve capacity. Conversely, a 60 min treatment with 2 mM MMS causes persistent mtDNA lesions but no mtDNA loss, no decrease in levels of a nuclear-encoded mitochondrial subunit, and no mitochondrial dysfunction. These results suggest that persistent mtDNA damage is not sufficient to cause mitochondrial dysfunction. PMID:22766155

  11. Detection of novel polymorphisms in the mitochondrial DNA D-Loop ...

    African Journals Online (AJOL)

    aghomotsegin

    2015-04-08

    Apr 8, 2015 ... 1Department of Molecular Biology, Babylon University, Hilla City, Iraq. 2Babylon ... Mitochondrial DNA (mtDNA) is a useful genetic marker for answering .... to you for choosing the project, your enthusiasm for helping us ...

  12. Mgm101p is a novel component of the mitochondrial nucleoid that binds DNA and is required for the repair of oxidatively damaged mitochondrial DNA

    International Nuclear Information System (INIS)

    Meeusen, S.; Tieu, Q.; Wong, E.; Weiss, E.; Schieltz, D.; Yates, J.R.; Nunnari, J.

    1999-01-01

    Maintenance of mitochondrial DNA (mtDNA) during cell division is required for progeny to be respiratory competent. Maintenance involves the replication, repair, assembly, segregation, and partitioning of the mitochondrial nucleoid. MGM101 has been identified as a gene essential for mtDNA maintenance in S. cerevisiae, but its role is unknown. Using liquid chromatography coupled with tandem mass spectrometry, we identified Mgm101p as a component of highly enriched nucleoids, suggesting that it plays a nucleoid-specific role in maintenance. Subcellular fractionation, indirect immunofluorescence and GFP tagging show that Mgm101p is exclusively associated with the mitochondrial nucleoid structure in cells. Furthermore, DNA affinity chromatography of nucleoid extracts indicates that Mgm101p binds to DNA, suggesting that its nucleoid localization is in part due to this activity. Phenotypic analysis of cells containing a temperature sensitive mgm101 allele suggests that Mgm101p is not involved in mtDNA packaging, segregation, partitioning or required for ongoing mtDNA replication. We examined Mgm101p's role in mtDNA repair. As compared with wild-type cells, mgm101 cells were more sensitive to mtDNA damage induced by UV irradiation and were hypersensitive to mtDNA damage induced by gamma rays and H2O2 treatment. Thus, we propose that Mgm101p performs an essential function in the repair of oxidatively damaged mtDNA that is required for the maintenance of the mitochondrial genome. (author)

  13. Evolutionary history of continental southeast Asians: "early train" hypothesis based on genetic analysis of mitochondrial and autosomal DNA data.

    Science.gov (United States)

    Jinam, Timothy A; Hong, Lih-Chun; Phipps, Maude E; Stoneking, Mark; Ameen, Mahmood; Edo, Juli; Saitou, Naruya

    2012-11-01

    The population history of the indigenous populations in island Southeast Asia is generally accepted to have been shaped by two major migrations: the ancient "Out of Africa" migration ∼50,000 years before present (YBP) and the relatively recent "Out of Taiwan" expansion of Austronesian agriculturalists approximately 5,000 YBP. The Negritos are believed to have originated from the ancient migration, whereas the majority of island Southeast Asians are associated with the Austronesian expansion. We determined 86 mitochondrial DNA (mtDNA) complete genome sequences in four indigenous Malaysian populations, together with a reanalysis of published autosomal single-nucleotide polymorphism (SNP) data of Southeast Asians to test the plausibility and impact of those migration models. The three Austronesian groups (Bidayuh, Selatar, and Temuan) showed high frequencies of mtDNA haplogroups, which originated from the Asian mainland ∼30,000-10,000 YBP, but low frequencies of "Out of Taiwan" markers. Principal component analysis and phylogenetic analysis using autosomal SNP data indicate a dichotomy between continental and island Austronesian groups. We argue that both the mtDNA and autosomal data suggest an "Early Train" migration originating from Indochina or South China around the late-Pleistocene to early-Holocene period, which predates, but may not necessarily exclude, the Austronesian expansion.

  14. Complete DNA sequence of the linear mitochondrial genome of the pathogenic yeast Candida parapsilosis

    DEFF Research Database (Denmark)

    Nosek, J.; Novotna, M.; Hlavatovicova, Z.

    2004-01-01

    The complete sequence of the mitochondrial DNA of the opportunistic yeast pathogen Candida parapsilosis was determined. The mitochondrial genome is represented by linear DNA molecules terminating with tandem repeats of a 738-bp unit. The number of repeats varies, thus generating a population...

  15. MitBASE : a comprehensive and integrated mitochondrial DNA database. The present status

    NARCIS (Netherlands)

    Attimonelli, M.; Altamura, N.; Benne, R.; Brennicke, A.; Cooper, J. M.; D'Elia, D.; Montalvo, A.; Pinto, B.; de Robertis, M.; Golik, P.; Knoop, V.; Lanave, C.; Lazowska, J.; Licciulli, F.; Malladi, B. S.; Memeo, F.; Monnerot, M.; Pasimeni, R.; Pilbout, S.; Schapira, A. H.; Sloof, P.; Saccone, C.

    2000-01-01

    MitBASE is an integrated and comprehensive database of mitochondrial DNA data which collects, under a single interface, databases for Plant, Vertebrate, Invertebrate, Human, Protist and Fungal mtDNA and a Pilot database on nuclear genes involved in mitochondrial biogenesis in Saccharomyces

  16. Alterations of mitochondrial DNA in CEM cells selected for resistance toward ddC toxicity.

    Science.gov (United States)

    Bjerke, M; Franco, M; Johansson, M; Balzarini, J; Karlsson, A

    2006-01-01

    2 ',3 '-dideoxycytidine (ddC) is a nucleoside analog that has been shown to produce a delayed toxicity which may be due to the depletion of mitochondrial DNA (mtDNA). In order to gain further understanding of the events involved in mitochondrial toxicity, two different CEM cell lines were selected for resistance to the delayed ddC toxicity.

  17. Mitochondrial DNA sequence variation in human evolution and disease.

    Science.gov (United States)

    Wallace, D C

    1994-09-13

    Germ-line and somatic mtDNA mutations are hypothesized to act together to shape our history and our health. Germ-line mtDNA mutations, both ancient and recent, have been associated with a variety of degenerative diseases. Mildly to moderately deleterious germ-line mutations, like neutral polymorphisms, have become established in the distant past through genetic drift but now may predispose certain individuals to late-onset degenerative diseases. As an example, a homoplasmic, Caucasian, tRNA(Gln) mutation at nucleotide pair (np) 4336 has been observed in 5% of Alzheimer disease and Parkinson disease patients and may contribute to the multifactorial etiology of these diseases. Moderately to severely deleterious germ-line mutations, on the other hand, appear repeatedly but are eliminated by selection. Hence, all extant mutations of this class are recent and associated with more devastating diseases of young adults and children. Representative of these mutations is a heteroplasmic mutation in MTND6 at np 14459 whose clinical presentations range from adult-onset blindness to pediatric dystonia and basal ganglial degeneration. To the inherited mutations are added somatic mtDNA mutations which accumulate in random arrays within stable tissues. These mutations provide a molecular clock that measures our age and may cause a progressive decline in tissue energy output that could precipitate the onset of degenerative diseases in individuals harboring inherited deleterious mutations.

  18. Mitochondrial DNA (mtDNA haplogroups in 1526 unrelated individuals from 11 Departments of Colombia

    Directory of Open Access Journals (Sweden)

    Juan J. Yunis

    2013-01-01

    Full Text Available The frequencies of four mitochondrial Native American DNA haplogroups were determined in 1526 unrelated individuals from 11 Departments of Colombia and compared to the frequencies previously obtained for Amerindian and Afro-Colombian populations. Amerindian mtDNA haplogroups ranged from 74% to 97%. The lowest frequencies were found in Departments on the Caribbean coast and in the Pacific region, where the frequency of Afro-Colombians is higher, while the highest mtDNA Amerindian haplogroup frequencies were found in Departments that historically have a strong Amerindian heritage. Interestingly, all four mtDNA haplogroups were found in all Departments, in contrast to the complete absence of haplogroup D and high frequencies of haplogroup A in Amerindian populations in the Caribbean region of Colombia. Our results indicate that all four Native American mtDNA haplogroups were widely distributed in Colombia at the time of the Spanish conquest.

  19. Nuclear Expression of a Mitochondrial DNA Gene: Mitochondrial Targeting of Allotopically Expressed Mutant ATP6 in Transgenic Mice

    Directory of Open Access Journals (Sweden)

    David A. Dunn

    2012-01-01

    Full Text Available Nuclear encoding of mitochondrial DNA transgenes followed by mitochondrial targeting of the expressed proteins (allotopic expression; AE represents a potentially powerful strategy for creating animal models of mtDNA disease. Mice were created that allotopically express either a mutant (A6M or wildtype (A6W mt-Atp6 transgene. Compared to non-transgenic controls, A6M mice displayed neuromuscular and motor deficiencies (wire hang, pole, and balance beam analyses; P0.05. This study illustrates a mouse model capable of circumventing in vivo mitochondrial mutations. Moreover, it provides evidence supporting AE as a tool for mtDNA disease research with implications in development of DNA-based therapeutics.

  20. Whole-loop mitochondrial DNA D-loop sequence variability in Egyptian Arabian equine matrilines

    Science.gov (United States)

    Hudson, William

    2017-01-01

    Background Egyptian Arabian horses have been maintained in a state of genetic isolation for over a hundred years. There is only limited genetic proof that the studbook records of female lines of Egyptian Arabian pedigrees are reliable. This study characterized the mitochondrial DNA (mtDNA) signatures of 126 horses representing 14 matrilines in the Egyptian Agricultural Organization (EAO) horse-breeding program. Findings Analysis of the whole D-loop sequence yielded additional information compared to hypervariable region-1 (HVR1) analysis alone, with 42 polymorphic sites representing ten haplotypes compared to 16 polymorphic sites representing nine haplotypes, respectively. Most EAO haplotypes belonged to ancient haplogroups, suggesting origin from a wide geographical area over many thousands of years, although one haplotype was novel. Conclusions Historical families share haplotypes and some individuals from different strains belonged to the same haplogroup: the classical EAO strain designation is not equivalent to modern monophyletic matrilineal groups. Phylogenetic inference showed that the foundation mares of the historical haplotypes were highly likely to have the same haplotypes as the animals studied (p > 0.998 in all cases), confirming the reliability of EAO studbook records and providing the opportunity for breeders to confirm the ancestry of their horses. PMID:28859174

  1. The Mitochondrial DNA (mtDNA)-Associated Protein SWIB5 Influences mtDNA Architecture and Homologous Recombination

    KAUST Repository

    Blomme, Jonas

    2017-04-19

    In addition to the nucleus, mitochondria and chloroplasts in plant cells also contain genomes. Efficient DNA repair pathways are crucial in these organelles to fix damage resulting from endogenous and exogenous factors. Plant organellar genomes are complex compared with their animal counterparts, and although several plant-specific mediators of organelle DNA repair have been reported, many regulators remain to be identified. Here, we show that a mitochondrial SWI/SNF (nucleosome remodeling) complex B protein, SWIB5, is capable of associating with mitochondrial DNA (mtDNA) in Arabidopsis thaliana. Gainand loss-of-function mutants provided evidence for a role of SWIB5 in influencing mtDNA architecture and homologous recombination at specific intermediate-sized repeats both under normal and genotoxic conditions. SWIB5 interacts with other mitochondrial SWIB proteins. Gene expression and mutant phenotypic analysis of SWIB5 and SWIB family members suggests a link between organellar genome maintenance and cell proliferation. Taken together, our work presents a protein family that influences mtDNA architecture and homologous recombination in plants and suggests a link between organelle functioning and plant development.

  2. Ancient DNA extracted from Danish aurochs (Bos primigenius)

    DEFF Research Database (Denmark)

    Nielsen, Peter Gravlund; Aaris-Sørensen, Kim; Hofreiter, Michael

    2012-01-01

    study of genetic variation of Danish aurochs. In addition, for all specimens we address correlations between the ability to obtain DNA sequences and various parameters such as the age of the sample, the collagen content, the museum storage period, Danish geography and whether the specimens were found...... in an archeological or geological context. We find that aurochs from southern Scandinavia display a star-shaped population genetic structure, that is indicative of a local and relatively recent diversification from a few ancestral haplotypes that may have originated in the ancestral Western European population before...... migration northwards during the retreat of the glaciers. Scenarios suggesting several invasions of genetically distinct aurochs are not supported by these analyses. Rather, our results suggest that a single continuous migration northward occurred. Our findings also suggest, although with only limited...

  3. Validation of the use of an artificial mitochondrial reporter DNA vector containing a Cytomegalovirus promoter for mitochondrial transgene expression.

    Science.gov (United States)

    Yamada, Yuma; Ishikawa, Takuya; Harashima, Hideyoshi

    2017-08-01

    Mitochondria have their own gene expression system that is independent of the nuclear system, and control cellular functions in cooperation with the nucleus. While a number of useful technologies for achieving nuclear transgene expression have been reported, only a few have focused on mitochondria. In this study, we validated the utility of an artificial mitochondrial DNA vector with a virus promoter on mitochondrial transgene expression. We designed and constructed pCMV-mtLuc (CGG) that contains a CMV promotor derived from Cytomegalovirus and an artificial mitochondrial genome with a NanoLuc (Nluc) luciferase gene that records adjustments to the mitochondrial codon system. Nluc luciferase activity measurements showed that the pCMV-mtLuc (CGG) efficiently produced the Nluc luciferase protein in human HeLa cells. Moreover, we optimized the mitochondrial transfection of pCMV-mtLuc (CGG) using a MITO-Porter system, a liposome-based carrier for mitochondrial delivery via membrane fusion. As a result, we found that transfection of pCMV-mtLuc (CGG) by MITO-Porter modified with the KALA peptide (cationic amphipathic cell-penetrating peptide) showed a high mitochondrial transgene expression. The developed mitochondrial transgene expression system represents a potentially useful tool for the fields of nanoscience and nanotechnology for controlling the intracellular microenvironment via the regulation of mitochondrial function and promises to open additional innovative research fields of study. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Taming the late Quaternary phylogeography of the Eurasiatic wild ass through ancient and modern DNA.

    Science.gov (United States)

    Bennett, E Andrew; Champlot, Sophie; Peters, Joris; Arbuckle, Benjamin S; Guimaraes, Silvia; Pruvost, Mélanie; Bar-David, Shirli; Davis, Simon J M; Gautier, Mathieu; Kaczensky, Petra; Kuehn, Ralph; Mashkour, Marjan; Morales-Muñiz, Arturo; Pucher, Erich; Tournepiche, Jean-François; Uerpmann, Hans-Peter; Bălăşescu, Adrian; Germonpré, Mietje; Gündem, Can Y; Hemami, Mahmoud-Reza; Moullé, Pierre-Elie; Ötzan, Aliye; Uerpmann, Margarete; Walzer, Chris; Grange, Thierry; Geigl, Eva-Maria

    2017-01-01

    Taxonomic over-splitting of extinct or endangered taxa, due to an incomplete knowledge of both skeletal morphological variability and the geographical ranges of past populations, continues to confuse the link between isolated extant populations and their ancestors. This is particularly problematic with the genus Equus. To more reliably determine the evolution and phylogeographic history of the endangered Asiatic wild ass, we studied the genetic diversity and inter-relationships of both extinct and extant populations over the last 100,000 years, including samples throughout its previous range from Western Europe to Southwest and East Asia. Using 229 bp of the mitochondrial hypervariable region, an approach which allowed the inclusion of information from extremely poorly preserved ancient samples, we classify all non-African wild asses into eleven clades that show a clear phylogeographic structure revealing their phylogenetic history. This study places the extinct European wild ass, E. hydruntinus, the phylogeny of which has been debated since the end of the 19th century, into its phylogenetic context within the Asiatic wild asses and reveals recent mitochondrial introgression between populations currently regarded as separate species. The phylogeographic organization of clades resulting from these efforts can be used not only to improve future taxonomic determination of a poorly characterized group of equids, but also to identify historic ranges, interbreeding events between various populations, and the impact of ancient climatic changes. In addition, appropriately placing extant relict populations into a broader phylogeographic and genetic context can better inform ongoing conservation strategies for this highly-endangered species.

  5. Ancient DNA reveals lack of continuity between neolithic hunter-gatherers and contemporary Scandinavians

    DEFF Research Database (Denmark)

    Malmström, Helena; Gilbert, M Thomas P; Thomas, Mark G

    2009-01-01

    of the two cultures in Scandinavia has been cited as an argument against population replacement between the Mesolithic and the present [7, 8]. Through analysis of DNA extracted from ancient Scandinavian human remains, we show that people of the Pitted Ware culture were not the direct ancestors of modern......]. Furthermore, our data are consistent with the view that the eastern Baltic represents a genetic refugia for some of the European hunter-gatherer populations....

  6. Joint Estimation of Contamination, Error and Demography for Nuclear DNA from Ancient Humans

    Science.gov (United States)

    Slatkin, Montgomery

    2016-01-01

    When sequencing an ancient DNA sample from a hominin fossil, DNA from present-day humans involved in excavation and extraction will be sequenced along with the endogenous material. This type of contamination is problematic for downstream analyses as it will introduce a bias towards the population of the contaminating individual(s). Quantifying the extent of contamination is a crucial step as it allows researchers to account for possible biases that may arise in downstream genetic analyses. Here, we present an MCMC algorithm to co-estimate the contamination rate, sequencing error rate and demographic parameters—including drift times and admixture rates—for an ancient nuclear genome obtained from human remains, when the putative contaminating DNA comes from present-day humans. We assume we have a large panel representing the putative contaminant population (e.g. European, East Asian or African). The method is implemented in a C++ program called ‘Demographic Inference with Contamination and Error’ (DICE). We applied it to simulations and genome data from ancient Neanderthals and modern humans. With reasonable levels of genome sequence coverage (>3X), we find we can recover accurate estimates of all these parameters, even when the contamination rate is as high as 50%. PMID:27049965

  7. Genetic origin of goat populations in Oman revealed by mitochondrial DNA analysis

    Science.gov (United States)

    Gaafar, Osman Mahgoub; Costa, Vânia; Neira, Agusto Luzuriaga; Al-Atiyat, Raed Mahmoud; Beja-Pereira, Albano

    2017-01-01

    The Sultanate of Oman has a complex mosaic of livestock species and production systems, but the genetic diversity, demographic history or origins of these Omani animals has not been expensively studied. Goats might constitute one of the most abundant and important domestic livestock species since the Neolithic transition. Here, we examined the genetic diversity, origin, population structure and demographic history of Omani goats. Specifically, we analyzed a 525-bp fragment of the first hypervariable region of the mitochondrial DNA (mtDNA) control region from 69 Omani individuals and compared this fragment with 17 mtDNA sequences from Somalia and Yemen as well as 18 wild goat species and 1,198 previously published goat sequences from neighboring countries. The studied goat breeds show substantial diversity. The haplotype and nucleotide diversities of Omani goats were found equal to 0.983 ± 0.006 and 0.0284 ± 0.014, respectively. The phylogenetic analyses allowed us to classify Omani goats into three mtDNA haplogroups (A, B and G): haplogroup A was found to be predominant and widely distributed and accounted for 80% of all samples, and haplogroups B and G exhibited low frequencies. Phylogenetic comparisons with wild goats revealed that five of the native Omani goat populations originate from Capra aegagrus. Furthermore, most comparisons of pairwise population FST values within and between these five Omani goat breeds as well as between Omani goats and nine populations from nearby countries were not significant. These results suggest strong gene flow among goat populations caused by the extensive transport of goats and the frequent movements of human populations in ancient Arabia. The findings improve our understanding of the migration routes of modern goats from their region of domestication into southeastern Arabia and thereby shed light on human migratory and commercial networks during historical times. PMID:29281717

  8. Genetic origin of goat populations in Oman revealed by mitochondrial DNA analysis.

    Science.gov (United States)

    Al-Araimi, Nasser Ali; Gaafar, Osman Mahgoub; Costa, Vânia; Neira, Agusto Luzuriaga; Al-Atiyat, Raed Mahmoud; Beja-Pereira, Albano

    2017-01-01

    The Sultanate of Oman has a complex mosaic of livestock species and production systems, but the genetic diversity, demographic history or origins of these Omani animals has not been expensively studied. Goats might constitute one of the most abundant and important domestic livestock species since the Neolithic transition. Here, we examined the genetic diversity, origin, population structure and demographic history of Omani goats. Specifically, we analyzed a 525-bp fragment of the first hypervariable region of the mitochondrial DNA (mtDNA) control region from 69 Omani individuals and compared this fragment with 17 mtDNA sequences from Somalia and Yemen as well as 18 wild goat species and 1,198 previously published goat sequences from neighboring countries. The studied goat breeds show substantial diversity. The haplotype and nucleotide diversities of Omani goats were found equal to 0.983 ± 0.006 and 0.0284 ± 0.014, respectively. The phylogenetic analyses allowed us to classify Omani goats into three mtDNA haplogroups (A, B and G): haplogroup A was found to be predominant and widely distributed and accounted for 80% of all samples, and haplogroups B and G exhibited low frequencies. Phylogenetic comparisons with wild goats revealed that five of the native Omani goat populations originate from Capra aegagrus. Furthermore, most comparisons of pairwise population FST values within and between these five Omani goat breeds as well as between Omani goats and nine populations from nearby countries were not significant. These results suggest strong gene flow among goat populations caused by the extensive transport of goats and the frequent movements of human populations in ancient Arabia. The findings improve our understanding of the migration routes of modern goats from their region of domestication into southeastern Arabia and thereby shed light on human migratory and commercial networks during historical times.

  9. Mitochondrial catalase overexpressed transgenic mice are protected against lung fibrosis in part via preventing alveolar epithelial cell mitochondrial DNA damage.

    Science.gov (United States)

    Kim, Seok-Jo; Cheresh, Paul; Jablonski, Renea P; Morales-Nebreda, Luisa; Cheng, Yuan; Hogan, Erin; Yeldandi, Anjana; Chi, Monica; Piseaux, Raul; Ridge, Karen; Michael Hart, C; Chandel, Navdeep; Scott Budinger, G R; Kamp, David W

    2016-12-01

    Alveolar epithelial cell (AEC) injury and mitochondrial dysfunction are important in the development of lung fibrosis. Our group has shown that in the asbestos exposed lung, the generation of mitochondrial reactive oxygen species (ROS) in AEC mediate mitochondrial DNA (mtDNA) damage and apoptosis which are necessary for lung fibrosis. These data suggest that mitochondrial-targeted antioxidants should ameliorate asbestos-induced lung. To determine whether transgenic mice that express mitochondrial-targeted catalase (MCAT) have reduced lung fibrosis following exposure to asbestos or bleomycin and, if so, whether this occurs in association with reduced AEC mtDNA damage and apoptosis. Crocidolite asbestos (100µg/50µL), TiO 2 (negative control), bleomycin (0.025 units/50µL), or PBS was instilled intratracheally in 8-10 week-old wild-type (WT - C57Bl/6J) or MCAT mice. The lungs were harvested at 21d. Lung fibrosis was quantified by collagen levels (Sircol) and lung fibrosis scores. AEC apoptosis was assessed by cleaved caspase-3 (CC-3)/Surfactant protein C (SFTPC) immunohistochemistry (IHC) and semi-quantitative analysis. AEC (primary AT2 cells from WT and MCAT mice and MLE-12 cells) mtDNA damage was assessed by a quantitative PCR-based assay, apoptosis was assessed by DNA fragmentation, and ROS production was assessed by a Mito-Sox assay. Compared to WT, crocidolite-exposed MCAT mice exhibit reduced pulmonary fibrosis as measured by lung collagen levels and lung fibrosis score. The protective effects in MCAT mice were accompanied by reduced AEC mtDNA damage and apoptosis. Similar findings were noted following bleomycin exposure. Euk-134, a mitochondrial SOD/catalase mimetic, attenuated MLE-12 cell DNA damage and apoptosis. Finally, compared to WT, asbestos-induced MCAT AT2 cell ROS production was reduced. Our finding that MCAT mice have reduced pulmonary fibrosis, AEC mtDNA damage and apoptosis following exposure to asbestos or bleomycin suggests an important role

  10. Mitochondrial nucleoid clusters protect newly synthesized mtDNA during Doxorubicin- and Ethidium Bromide-induced mitochondrial stress

    Czech Academy of Sciences Publication Activity Database

    Alán, Lukáš; Špaček, Tomáš; Pajuelo-Reguera, David; Jabůrek, Martin; Ježek, Petr

    2016-01-01

    Roč. 302, Jul 1 (2016), s. 31-40 ISSN 0041-008X R&D Projects: GA ČR(CZ) GAP305/12/1247; GA MŠk(CZ) LQ1604; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:67985823 Keywords : Doxorubicin * Ethidium Bromide * nucleoid clusters * mitochondrial DNA stress * mitochondrial transcription factor A Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.791, year: 2016

  11. Mitochondrial DNA phylogeny of camel spiders (Arachnida: Solifugae) from Iran.

    Science.gov (United States)

    Maddahi, Hassan; Khazanehdari, Mahsa; Aliabadian, Mansour; Kami, Haji Gholi; Mirshamsi, Amin; Mirshamsi, Omid

    2017-11-01

    In the present study, the mitochondrial DNA phylogeny of five solifuge families of Iran is presented using phylogenetic analysis of mitochondrial cytochrome c oxidase, subunit 1 (COI) sequence data. Moreover, we included available representatives from seven families from GenBank to examine the genetic distance between Old and New World taxa and test the phylogenetic relationships among more solifuge families. Phylogenetic relationships were reconstructed based on the two most probabilistic methods, Maximum Likelihood (ML) and Bayesian inference (BI) approaches. Resulting topologies demonstrated the monophyly of the families Daesiidae, Eremobatidae, Galeodidae, Karschiidae and Rhagodidae, whereas the monophyly of the families Ammotrechidae and Gylippidae was not supported. Also, within the family Eremobatidae, the subfamilies Eremobatinae and Therobatinae and the genus Hemerotrecha were paraphyletic or polyphyletic. According to the resulted topologies, the taxonomic placements of Trichotoma michaelseni (Gylippidae) and Nothopuga sp. 1 (Ammotrechidae) are still remain under question and their revision might be appropriate. According to the results of this study, within the family Galeodidae, the validity of the genus Galeodopsis is supported, while the validity of the genus Paragaleodes still remains uncertain. Moreover, our results revealed that the species Galeodes bacillatus, and Rhagodes melanochaetus are junior synonyms of G. caspius, and R. eylandti, respectively.

  12. First description of a novel mitochondrial mutation in the MT-TI gene associated with multiple mitochondrial DNA deletion and depletion in family with severe dilated mitochondrial cardiomyopathy.

    Science.gov (United States)

    Alila-Fersi, Olfa; Tabebi, Mouna; Maalej, Marwa; Belguith, Neila; Keskes, Leila; Mkaouar-Rebai, Emna; Fakhfakh, Faiza

    2018-03-18

    Mitochondria are essential for early cardiac development and impaired mitochondrial function was described associated with heart diseases such as hypertrophic or dilated mitochondrial cardiomyopathy. In this study, we report a family including two individuals with severe dilated mitochondrial cardiomyopathy. The whole mitochondrial genome screening showed the presence of several variations and a novel homoplasmic mutation m.4318-4322delC in the MT-TI gene shared by the two patients and their mother and leading to a disruption of the tRNA Ile secondary structure. In addition, a mitochondrial depletion was present in blood leucocyte of the two affected brother whereas a de novo heteroplasmic multiple deletion in the major arc of mtDNA was present in blood leucocyte and mucosa of only one of them. These deletions in the major arc of the mtDNA resulted to the loss of several protein-encoding genes and also some tRNA genes. The mtDNA deletion and depletion could result to an impairment of the oxidative phosphorylation and energy metabolism in the respiratory chain in the studied patients. Our report is the first description of a family with severe lethal dilated mitochondrial cardiomyopathy and presenting several mtDNA abnormalities including punctual mutation, deletion and depletion. Copyright © 2018 Elsevier Inc. All rights reserved.

  13. DNA Sequences Proximal to Human Mitochondrial DNA Deletion Breakpoints Prevalent in Human Disease Form G-quadruplexes, a Class of DNA Structures Inefficiently Unwound by the Mitochondrial Replicative Twinkle Helicase*

    Science.gov (United States)

    Bharti, Sanjay Kumar; Sommers, Joshua A.; Zhou, Jun; Kaplan, Daniel L.; Spelbrink, Johannes N.; Mergny, Jean-Louis; Brosh, Robert M.

    2014-01-01

    Mitochondrial DNA deletions are prominent in human genetic disorders, cancer, and aging. It is thought that stalling of the mitochondrial replication machinery during DNA synthesis is a prominent source of mitochondrial genome instability; however, the precise molecular determinants of defective mitochondrial replication are not well understood. In this work, we performed a computational analysis of the human mitochondrial genome using the “Pattern Finder” G-quadruplex (G4) predictor algorithm to assess whether G4-forming sequences reside in close proximity (within 20 base pairs) to known mitochondrial DNA deletion breakpoints. We then used this information to map G4P sequences with deletions characteristic of representative mitochondrial genetic disorders and also those identified in various cancers and aging. Circular dichroism and UV spectral analysis demonstrated that mitochondrial G-rich sequences near deletion breakpoints prevalent in human disease form G-quadruplex DNA structures. A biochemical analysis of purified recombinant human Twinkle protein (gene product of c10orf2) showed that the mitochondrial replicative helicase inefficiently unwinds well characterized intermolecular and intramolecular G-quadruplex DNA substrates, as well as a unimolecular G4 substrate derived from a mitochondrial sequence that nests a deletion breakpoint described in human renal cell carcinoma. Although G4 has been implicated in the initiation of mitochondrial DNA replication, our current findings suggest that mitochondrial G-quadruplexes are also likely to be a source of instability for the mitochondrial genome by perturbing the normal progression of the mitochondrial replication machinery, including DNA unwinding by Twinkle helicase. PMID:25193669

  14. The mitochondrial outer membrane protein MDI promotes local protein synthesis and mtDNA replication.

    Science.gov (United States)

    Zhang, Yi; Chen, Yong; Gucek, Marjan; Xu, Hong

    2016-05-17

    Early embryonic development features rapid nuclear DNA replication cycles, but lacks mtDNA replication. To meet the high-energy demands of embryogenesis, mature oocytes are furnished with vast amounts of mitochondria and mtDNA However, the cellular machinery driving massive mtDNA replication in ovaries remains unknown. Here, we describe a Drosophila AKAP protein, MDI that recruits a translation stimulator, La-related protein (Larp), to the mitochondrial outer membrane in ovaries. The MDI-Larp complex promotes the synthesis of a subset of nuclear-encoded mitochondrial proteins by cytosolic ribosomes on the mitochondrial surface. MDI-Larp's targets include mtDNA replication factors, mitochondrial ribosomal proteins, and electron-transport chain subunits. Lack of MDI abolishes mtDNA replication in ovaries, which leads to mtDNA deficiency in mature eggs. Targeting Larp to the mitochondrial outer membrane independently of MDI restores local protein synthesis and rescues the phenotypes of mdi mutant flies. Our work suggests that a selective translational boost by the MDI-Larp complex on the outer mitochondrial membrane might be essential for mtDNA replication and mitochondrial biogenesis during oogenesis. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  15. Mitochondrial depolarization in yeast zygotes inhibits clonal expansion of selfish mtDNA.

    Science.gov (United States)

    Karavaeva, Iuliia E; Golyshev, Sergey A; Smirnova, Ekaterina A; Sokolov, Svyatoslav S; Severin, Fedor F; Knorre, Dmitry A

    2017-04-01

    Non-identical copies of mitochondrial DNA (mtDNA) compete with each other within a cell and the ultimate variant of mtDNA present depends on their relative replication rates. Using yeast Saccharomyces cerevisiae cells as a model, we studied the effects of mitochondrial inhibitors on the competition between wild-type mtDNA and mutant selfish mtDNA in heteroplasmic zygotes. We found that decreasing mitochondrial transmembrane potential by adding uncouplers or valinomycin changes the competition outcomes in favor of the wild-type mtDNA. This effect was significantly lower in cells with disrupted mitochondria fission or repression of the autophagy-related genes ATG8 , ATG32 or ATG33 , implying that heteroplasmic zygotes activate mitochondrial degradation in response to the depolarization. Moreover, the rate of mitochondrially targeted GFP turnover was higher in zygotes treated with uncoupler than in haploid cells or untreated zygotes. Finally, we showed that vacuoles of zygotes with uncoupler-activated autophagy contained DNA. Taken together, our data demonstrate that mitochondrial depolarization inhibits clonal expansion of selfish mtDNA and this effect depends on mitochondrial fission and autophagy. These observations suggest an activation of mitochondria quality control mechanisms in heteroplasmic yeast zygotes. © 2017. Published by The Company of Biologists Ltd.

  16. Mitochondrial DNA variation and genetic relationships of Populus species.

    Science.gov (United States)

    Barrett, J W; Rajora, O P; Yeh, F C; Dancik, B P; Strobeck, C

    1993-02-01

    We examined variation in and around the region coding for the cytochrome c oxidase I (coxI) and ATPase 6 (atp6) genes in the mitochondrial genomes of four Populus species (P. nigra, P. deltoides, P. maximowiczii, and P. tremuloides) and the natural hybrid P. x canadensis (P. deltoides x P. nigra). Total cellular DNAs of these poplars were digested with 16 restriction endonucleases and probed with maize mtDNA-specific probes (CoxI and Atp6). The only variant observed for Atp6 was interspecific, with P. maximowiczii separated from the other species as revealed by EcoRI digestions. No intraspecific mtDNA variation was observed among individuals of P. nigra, P. maximowiczii, P. x canadensis, or P. tremuloides for the CoxI probe. However, two varieties of P. deltoides were distinct because of a single site change in the KpnI digestions, demonstrating that P. deltoides var. deltoides (eastern cottonwood) and var. occidentalis (plains cottonwood) have distinct mitochondrial genomes in the region of the coxI gene. Populus x canadensis shared the same restriction fragment patterns as its suspected maternal parent P. deltoides. Nucleotide substitutions per base in and around the coxI and atp6 genes among the Populus species and the hybrid ranged from 0.0017 to 0.0077. The interspecific estimates of nucleotide substitution per base suggested that P. tremuloides was furthest removed from P. deltoides and P. x canadensis and least diverged from P. nigra. Populus maximowiczii was placed between these two clusters.

  17. Selective Gene Delivery for Integrating Exogenous DNA into Plastid and Mitochondrial Genomes Using Peptide-DNA Complexes.

    Science.gov (United States)

    Yoshizumi, Takeshi; Oikawa, Kazusato; Chuah, Jo-Ann; Kodama, Yutaka; Numata, Keiji

    2018-05-14

    Selective gene delivery into organellar genomes (mitochondrial and plastid genomes) has been limited because of a lack of appropriate platform technology, even though these organelles are essential for metabolite and energy production. Techniques for selective organellar modification are needed to functionally improve organelles and produce transplastomic/transmitochondrial plants. However, no method for mitochondrial genome modification has yet been established for multicellular organisms including plants. Likewise, modification of plastid genomes has been limited to a few plant species and algae. In the present study, we developed ionic complexes of fusion peptides containing organellar targeting signal and plasmid DNA for selective delivery of exogenous DNA into the plastid and mitochondrial genomes of intact plants. This is the first report of exogenous DNA being integrated into the mitochondrial genomes of not only plants, but also multicellular organisms in general. This fusion peptide-mediated gene delivery system is a breakthrough platform for both plant organellar biotechnology and gene therapy for mitochondrial diseases in animals.

  18. A mitochondrial DNA SNP multiplex assigning Caucasians into 36 haplo- and subhaplogroups

    DEFF Research Database (Denmark)

    Mikkelsen, Martin; Rockenbauer, Eszter; Sørensen, Erik

    2008-01-01

    Mitochondrial DNA (mtDNA) is maternally inherited without recombination events and has a high copy number, which makes mtDNA analysis feasible even when genomic DNA is sparse or degraded. Here, we present a SNP typing assay with 33 previously described mtDNA coding region SNPs for haplogroup...... previously typed by sequencing of the mitochondrial HV1 and HV2 regions. Haplogroup assignments based on mtDNA coding region SNPs and sequencing of HV1 and HV2 regions gave identical results for 27% of the samples, and except for one sample, differences in haplogroup assignments were at the subhaplogroup...

  19. Genetic polymorphisms in prehistoric Pacific islanders determined by analysis of ancient bone DNA.

    Science.gov (United States)

    Hagelberg, E; Clegg, J B

    1993-05-22

    A previously characterized Asian-specific mitochondrial DNA (mtDNA) length mutation has been detected in DNA isolated from prehistoric human bones from Polynesia, including Hawaii, Chatham Islands and Society Islands. In contrast, the Asian mutation was absent in skeletal samples from the Melanesian archipelagos of New Britain and Vanuatu and in the oldest samples from Fiji, Tonga and Samoa in the central Pacific (2700-1600 years BP) although it was present in a more recent prehistoric sample from Tonga. These results, augmented by informative DNA sequence data from the hypervariable region of mtDNA, fail to support current views that the central Pacific was settled directly by voyagers from island Southeast Asia, the putative ancestors of modern Polynesians. An earlier occupation by peoples from the neighbouring Melanesian archipelagos seems more likely.

  20. The last Viking King: a royal maternity case solved by ancient DNA analysis

    DEFF Research Database (Denmark)

    Dissing, Jørgen; Binladen, Jonas; Hansen, Anders

    2006-01-01

    Estridsen to haplogroup H; Estrid's sequence differed from that of Sven at two positions in HVR-1, 16093T-->C and 16304T-->C, indicating that she belongs to subgroup H5a. Given the maternal inheritance of mtDNA, offspring will have the same mtDNA sequence as their mother with the exception of rare cases...... doubts among historians whether the woman entombed was indeed Estrid. To shed light on this problem, we have extracted and analysed mitochondrial DNA (mtDNA) from pulp of teeth from each of the two royals. Four overlapping DNA-fragments covering about 400bp of hypervariable region 1 (HVR-1) of the D...

  1. Ancient microbes from halite fluid inclusions: optimized surface sterilization and DNA extraction.

    Science.gov (United States)

    Sankaranarayanan, Krithivasan; Timofeeff, Michael N; Spathis, Rita; Lowenstein, Tim K; Lum, J Koji

    2011-01-01

    Fluid inclusions in evaporite minerals (halite, gypsum, etc.) potentially preserve genetic records of microbial diversity and changing environmental conditions of Earth's hydrosphere for nearly one billion years. Here we describe a robust protocol for surface sterilization and retrieval of DNA from fluid inclusions in halite that, unlike previously published methods, guarantees removal of potentially contaminating surface-bound DNA. The protocol involves microscopic visualization of cell structures, deliberate surface contamination followed by surface sterilization with acid and bleach washes, and DNA extraction using Amicon centrifugal filters. Methods were verified on halite crystals of four different ages from Saline Valley, California (modern, 36 ka, 64 ka, and 150 ka), with retrieval of algal and archaeal DNA, and characterization of the algal community using ITS1 sequences. The protocol we developed opens up new avenues for study of ancient microbial ecosystems in fluid inclusions, understanding microbial evolution across geological time, and investigating the antiquity of life on earth and other parts of the solar system.

  2. Mitochondrial DNA Damage and Diseases [version 1; referees: 1 approved, 2 approved with reservations

    Directory of Open Access Journals (Sweden)

    Gyanesh Singh

    2015-07-01

    Full Text Available Various endogenous and environmental factors can cause mitochondrial DNA (mtDNA damage.  One of the reasons for enhanced mtDNA damage could be its proximity to the source of oxidants, and lack of histone-like protective proteins. Moreover, mitochondria contain inadequate DNA repair pathways, and, diminished DNA repair capacity may be one of the factors responsible for high mutation frequency of the mtDNA. mtDNA damage might cause impaired mitochondrial function, and, unrepaired mtDNA damage has been frequently linked with several diseases. Exploration of mitochondrial perspective of diseases might lead to a better understanding of several diseases, and will certainly open new avenues for detection, cure, and prevention of ailments.

  3. Associations of mitochondrial haplogroups and mitochondrial DNA copy numbers with end-stage renal disease in a Han population.

    Science.gov (United States)

    Zhang, Yuheng; Zhao, Ying; Wen, Shuzhen; Yan, Rengna; Yang, Qinglan; Chen, Huimei

    2017-09-01

    Mitochondrial DNA (mtDNA) is closely related to mitochondrion function, and variations have been suggested to be involved in pathogenesis of complex diseases. The present study sought to elucidate mitochondrial haplogroups and mtDNA copy number in end-stage renal disease (ESRD) in a Han population. First, the mitochondrial haplogroups of 37 ESRD patients were clustered into several haplogroups, and haplogroup A & D were taken as the candidate risk haplogroups for ESRD. Second, the frequencies of A and D were assessed in 344 ESRD patients and 438 healthy controls, respectively. Haplogroup D was found to be risk maker for ESRD in young subjects (numbers were evaluated with quantitative-PCR. The ESRD patients exhibited greater cell-free mtDNA contents than the healthy controls but less intracellular mtDNA. Haplogroup D exhibited a further increase in cell-free mtDNA content and a decrease in intracellular mtDNA content among the ESRDs patients. Our findings suggest that mtNDA haplogroup D may contributes to pathogenesis of early-onset ESRD through alterations of mtDNA copy numbers.

  4. Overexpression of DNA ligase III in mitochondria protects cells against oxidative stress and improves mitochondrial DNA base excision repair

    DEFF Research Database (Denmark)

    Akbari, Mansour; Keijzers, Guido; Maynard, Scott

    2014-01-01

    slower than the preceding mitochondrial BER steps. Overexpression of DNA ligase III in mitochondria improved the rate of overall BER, increased cell survival after menadione induced oxidative stress and reduced autophagy following the inhibition of the mitochondrial electron transport chain complex I...

  5. Mitochondrial DNA damage and vascular function in patients with diabetes mellitus and atherosclerotic cardiovascular disease.

    Science.gov (United States)

    Fetterman, Jessica L; Holbrook, Monica; Westbrook, David G; Brown, Jamelle A; Feeley, Kyle P; Bretón-Romero, Rosa; Linder, Erika A; Berk, Brittany D; Weisbrod, Robert M; Widlansky, Michael E; Gokce, Noyan; Ballinger, Scott W; Hamburg, Naomi M

    2016-03-31

    Prior studies demonstrate mitochondrial dysfunction with increased reactive oxygen species generation in peripheral blood mononuclear cells in diabetes mellitus. Oxidative stress-mediated damage to mitochondrial DNA promotes atherosclerosis in animal models. Thus, we evaluated the relation of mitochondrial DNA damage in peripheral blood mononuclear cells s with vascular function in patients with diabetes mellitus and with atherosclerotic cardiovascular disease. We assessed non-invasive vascular function and mitochondrial DNA damage in 275 patients (age 57 ± 9 years, 60 % women) with atherosclerotic cardiovascular disease alone (N = 55), diabetes mellitus alone (N = 74), combined atherosclerotic cardiovascular disease and diabetes mellitus (N = 48), and controls age >45 without diabetes mellitus or atherosclerotic cardiovascular disease (N = 98). Mitochondrial DNA damage measured by quantitative PCR in peripheral blood mononuclear cells was higher with clinical atherosclerosis alone (0.55 ± 0.65), diabetes mellitus alone (0.65 ± 1.0), and combined clinical atherosclerosis and diabetes mellitus (0.89 ± 1.32) as compared to control subjects (0.23 ± 0.64, P < 0.0001). In multivariable models adjusting for age, sex, and relevant cardiovascular risk factors, clinical atherosclerosis and diabetes mellitus remained associated with higher mitochondrial DNA damage levels (β = 0.14 ± 0.13, P = 0.04 and β = 0.21 ± 0.13, P = 0.002, respectively). Higher mitochondrial DNA damage was associated with higher baseline pulse amplitude, a measure of arterial pulsatility, but not with flow-mediated dilation or hyperemic response, measures of vasodilator function. We found greater mitochondrial DNA damage in patients with diabetes mellitus and clinical atherosclerosis. The association of mitochondrial DNA damage and baseline pulse amplitude may suggest a link between mitochondrial dysfunction and excessive small artery pulsatility with potentially adverse microvascular impact.

  6. An Analysis of Enzyme Kinetics Data for Mitochondrial DNA Strand Termination by Nucleoside Reverse Transcription Inhibitors

    Science.gov (United States)

    Wendelsdorf, Katherine V.; Song, Zhuo; Cao, Yang; Samuels, David C.

    2009-01-01

    Nucleoside analogs used in antiretroviral treatment have been associated with mitochondrial toxicity. The polymerase-γ hypothesis states that this toxicity stems from the analogs' inhibition of the mitochondrial DNA polymerase (polymerase-γ) leading to mitochondrial DNA (mtDNA) depletion. We have constructed a computational model of the interaction of polymerase-γ with activated nucleoside and nucleotide analog drugs, based on experimentally measured reaction rates and base excision rates, together with the mtDNA genome size, the human mtDNA sequence, and mitochondrial dNTP concentrations. The model predicts an approximately 1000-fold difference in the activated drug concentration required for a 50% probability of mtDNA strand termination between the activated di-deoxy analogs d4T, ddC, and ddI (activated to ddA) and the activated forms of the analogs 3TC, TDF, AZT, FTC, and ABC. These predictions are supported by experimental and clinical data showing significantly greater mtDNA depletion in cell culture and patient samples caused by the di-deoxy analog drugs. For zidovudine (AZT) we calculated a very low mtDNA replication termination probability, in contrast to its reported mitochondrial toxicity in vitro and clinically. Therefore AZT mitochondrial toxicity is likely due to a mechanism that does not involve strand termination of mtDNA replication. PMID:19132079

  7. Characterizing genetic diversity of contemporary pacific chickens using mitochondrial DNA analyses.

    Directory of Open Access Journals (Sweden)

    Kelsey Needham Dancause

    Full Text Available BACKGROUND: Mitochondrial DNA (mtDNA hypervariable region (HVR sequences of prehistoric Polynesian chicken samples reflect dispersal of two haplogroups--D and E--by the settlers of the Pacific. The distribution of these chicken haplogroups has been used as an indicator of human movement. Recent analyses suggested similarities between prehistoric Pacific and South American chicken samples, perhaps reflecting prehistoric Polynesian introduction of the chicken into South America. These analyses have been heavily debated. The current distribution of the D and E lineages among contemporary chicken populations in the Western Pacific is unclear, but might ultimately help to inform debates about the movements of humans that carried them. OBJECTIVES: We sought to characterize contemporary mtDNA diversity among chickens in two of the earliest settled archipelagos of Remote Oceania, the Marianas and Vanuatu. METHODS: We generated HVR sequences for 43 chickens from four islands in Vanuatu, and for 5 chickens from Guam in the Marianas. RESULTS: Forty samples from Vanuatu and three from Guam were assigned to haplogroup D, supporting this as a Pacific chicken haplogroup that persists in the Western Pacific. Two haplogroup E lineages were observed in Guam and two in Vanuatu. Of the E lineages in Vanuatu, one was identical to prehistoric Vanuatu and Polynesian samples and the other differed by one polymorphism. Contrary to our expectations, we observed few globally distributed domesticate lineages not associated with Pacific chicken dispersal. This might suggest less European introgression of chickens into Vanuatu than expected. If so, the E lineages might represent lineages maintained from ancient Pacific chicken introductions. The Vanuatu sample might thus provide an opportunity to distinguish between maintained ancestral Pacific chicken lineages and replacement by global domesticates through genomic analyses, which could resolve questions of contemporary

  8. Endurance exercise rescues progeroid aging and induces systemic mitochondrial rejuvenation in mtDNA mutator mice

    Science.gov (United States)

    Safdar, Adeel; Bourgeois, Jacqueline M.; Ogborn, Daniel I.; Little, Jonathan P.; Hettinga, Bart P.; Akhtar, Mahmood; Thompson, James E.; Melov, Simon; Mocellin, Nicholas J.; Kujoth, Gregory C.; Prolla, Tomas A.; Tarnopolsky, Mark A.

    2011-01-01

    A causal role for mitochondrial DNA (mtDNA) mutagenesis in mammalian aging is supported by recent studies demonstrating that the mtDNA mutator mouse, harboring a defect in the proofreading-exonuclease activity of mitochondrial polymerase gamma, exhibits accelerated aging phenotypes characteristic of human aging, systemic mitochondrial dysfunction, multisystem pathology, and reduced lifespan. Epidemiologic studies in humans have demonstrated that endurance training reduces the risk of chronic diseases and extends life expectancy. Whether endurance exercise can attenuate the cumulative systemic decline observed in aging remains elusive. Here we show that 5 mo of endurance exercise induced systemic mitochondrial biogenesis, prevented mtDNA depletion and mutations, increased mitochondrial oxidative capacity and respiratory chain assembly, restored mitochondrial morphology, and blunted pathological levels of apoptosis in multiple tissues of mtDNA mutator mice. These adaptations conferred complete phenotypic protection, reduced multisystem pathology, and prevented premature mortality in these mice. The systemic mitochondrial rejuvenation through endurance exercise promises to be an effective therapeutic approach to mitigating mitochondrial dysfunction in aging and related comorbidities. PMID:21368114

  9. SL1 RNA gene recovery from Enterobius vermicularis ancient DNA in pre-Columbian human coprolites.

    Science.gov (United States)

    Iñiguez, Alena Mayo; Reinhard, Karl; Carvalho Gonçalves, Marcelo Luiz; Ferreira, Luiz Fernando; Araújo, Adauto; Paulo Vicente, Ana Carolina

    2006-11-01

    Enterobius vermicularis, pinworm, is one of the most common helminths worldwide, infecting nearly a billion people at all socio-economic levels. In prehistoric populations the paleoparasitological findings show a pinworm homogeneous distribution among hunter-gatherers in North America, intensified with the advent of agriculture. This same increase also occurred in the transition from nomad hunter-gatherers to sedentary farmers in South America, although E. vermicularis infection encompasses only the ancient Andean peoples, with no record among the pre-Colombian populations in the South American lowlands. However, the outline of pinworm paleoepidemiology has been supported by microscopic finding of eggs recovered from coprolites. Since molecular techniques are precise and sensitive in detecting pathogen ancient DNA (aDNA), and also could provide insights into the parasite evolutionary history, in this work we have performed a molecular paleoparasitological study of E. vermicularis. aDNA was recovered and pinworm 5S rRNA spacer sequences were determined from pre-Columbian coprolites (4110 BC-AD 900) from four different North and South American archaeological sites. The sequence analysis confirmed E. vermicularis identity and revealed a similarity among ancient and modern sequences. Moreover, polymorphisms were identified at the relative positions 160, 173 and 180, in independent coprolite samples from Tulán, San Pedro de Atacama, Chile (1080-950 BC). We also verified the presence of peculiarities (Splicing leader (SL1) RNA sequence, spliced donor site, the Sm antigen biding site, and RNA secondary structure) which characterise the SL1 RNA gene. The analysis shows that the SL1 RNA gene of contemporary pinworms was present in pre-Columbian E. vermicularis by 6110 years ago. We were successful in detecting E. vermicularis aDNA even in coprolites without direct microscopic evidence of the eggs, improving the diagnosis of helminth infections in the past and further

  10. King penguin population on Macquarie Island recovers ancient DNA diversity after heavy exploitation in historic times.

    Science.gov (United States)

    Heupink, Tim H; van den Hoff, John; Lambert, David M

    2012-08-23

    Historically, king penguin populations on Macquarie Island have suffered greatly from human exploitation. Two large colonies on the island were drastically reduced to a single small colony as a result of harvesting for the blubber oil industry. However, recent conservation efforts have resulted in the king penguin population expanding in numbers and range to recolonize previous as well as new sites. Ancient DNA methods were used to estimate past genetic diversity and combined with studies of modern populations, we are now able to compare past levels of variation with extant populations on northern Macquarie Island. The ancient and modern populations are closely related and show a similar level of genetic diversity. These results suggest that the king penguin population has recovered past genetic diversity in just 80 years owing to conservation efforts, despite having seen the brink of extinction.

  11. A preliminary analysis of the DNA and diet of the extinct Beothuk: a systematic approach to ancient human DNA

    DEFF Research Database (Denmark)

    Kuch, Melanie; Gröcke, Darren R; Knyf, Martin C

    2007-01-01

    , which fall within haplogroups X and C, consistent with Northeastern Native populations today. In addition we have sexed the male using a novel-sexing assay and confirmed the authenticity of his Y chromosome with the presence of the Native American specific Y-QM3 single nucleotide polymorphism (SNP......). This is the first ancient nuclear SNP typed from a Native population in the Americas. In addition, using the same teeth we conducted a stable isotopes analysis of collagen and dentine to show that both individuals relied on marine sources (fresh and salt water fish, seals) with no hierarchy seen between them......, Nonosabasut) were of admixed (European-Native American) descent. We also analyzed patterns of DNA damage in the clones of authentic mtDNA sequences; there is no tendency for DNA damage to occur preferentially at previously defined mutational hotspots, suggesting that such mutational hotspots...

  12. The characterization of Helicobacter pylori DNA associated with ancient human remains recovered from a Canadian glacier.

    Directory of Open Access Journals (Sweden)

    Treena Swanston

    2011-02-01

    Full Text Available Helicobacter pylori is a gram-negative bacterium that colonizes the stomach of nearly half of the world's population. Genotypic characterization of H. pylori strains involves the analysis of virulence-associated genes, such as vacA, which has multiple alleles. Previous phylogenetic analyses have revealed a connection between modern H. pylori strains and the movement of ancient human populations. In this study, H. pylori DNA was amplified from the stomach tissue of the Kwäday Dän Ts'ìnchi individual. This ancient individual was recovered from the Samuel Glacier in Tatshenshini-Alsek Park, British Columbia, Canada on the traditional territory of the Champagne and Aishihik First Nations and radiocarbon dated to a timeframe of approximately AD 1670 to 1850. This is the first ancient H. pylori strain to be characterized with vacA sequence data. The Tatshenshini H. pylori strain has a potential hybrid vacA m2a/m1d middle (m region allele and a vacA s2 signal (s region allele. A vacA s2 allele is more commonly identified with Western strains, and this suggests that European strains were present in northwestern Canada during the ancient individual's time. Phylogenetic analysis indicated that the vacA m1d region of the ancient strain clusters with previously published novel Native American strains that are closely related to Asian strains. This indicates a past connection between the Kwäday Dän Ts'ìnchi individual and the ancestors who arrived in the New World thousands of years ago.

  13. Association between mitochondrial DNA variations and Alzheimer's Disease in the ADNI cohort

    Science.gov (United States)

    Lakatos, Anita; Derbeneva, Olga; Younes, Danny; Keator, David; Bakken, Trygve; Lvova, Maria; Brandon, Marty; Guffanti, Guia; Reglodi, Dora; Saykin, Andrew; Weiner, Michael; Macciardi, Fabio; Schork, Nicholas; Wallace, Douglas C.; Potkin, Steven G.

    2010-01-01

    Despite the central role of amyloid deposition in the development of Alzheimer's disease (AD), the pathogenesis of AD still remains elusive at the molecular level. Increasing evidence suggests that compromised mitochondrial function contributes to the aging process and thus may increase the risk of AD. Dysfunctional mitochondria contribute to reactive oxygen species (ROS) which can lead to extensive macromolecule oxidative damage and the progression of amyloid pathology. Oxidative stress and amyloid toxicity leave neurons chemically vulnerable. Because the brain relies on aerobic metabolism, it is apparent that mitochondria are critical for the cerebral function. Mitochondrial DNA sequence-changes could shift cell dynamics and facilitate neuronal vulnerability. Therefore we postulated that mitochondrial DNA sequence polymorphisms may increase the risk of AD. We evaluated the role of mitochondrial haplogroups derived from 138 mitochondrial polymorphisms in 358 Caucasian ADNI subjects. Our results indicate that the mitochondrial haplogroup UK may confer genetic susceptibility to AD independently of the APOE4 allele. PMID:20538375

  14. Quantification of the mitochondrial DNA common deletion in presbycusis.

    Science.gov (United States)

    Markaryan, Adam; Nelson, Erik G; Hinojosa, Raul

    2009-06-01

    This study was conducted to evaluate the association between the mitochondrial DNA (mtDNA) common deletion (CD) level in cochlear tissue and the severity of hearing loss in individuals with presbycusis. Nineteen individuals with presbycusis, ranging from 60 to 87 years of age, who met strict audiometric criteria were compared with four age frequency-matched normal hearing controls ranging from 51 to 76 years of age. Five additional normal hearing individuals, ranging from 9 to 50 years of age, were also studied. A duplex real time polymerase chain reaction assay was used to quantify the mtDNA in archival cochlear tissue samples. Linear regression models were used for comparison of the CD level between groups. The presbycusis group had a mean CD level of 32% with a standard deviation of 14%, and the normal hearing age matched control group had a mean CD level of 12% with a standard deviation of 2%. This difference in CD levels reached statistical significance (P = .011) and remained significant after adjusting for any differences in age between the two groups (age-adjusted P = .007). Furthermore, there was evidence for a significant association between the CD level and the severity of hearing loss based on audiometric thresholds at 8 kHz (r = 0.44, P = .034; age-adjusted partial correlation = 0.55, P = .007). For the first time, to our knowledge, these results demonstrate a relationship between quantitatively measured levels of the CD in human cochlear tissue and the severity of hearing loss in individuals with presbycusis. Laryngoscope, 2009.

  15. Endangered species: mitochondrial DNA loss as a mechanism of human disease.

    Science.gov (United States)

    Herrera, Alan; Garcia, Iraselia; Gaytan, Norma; Jones, Edith; Maldonado, Alicia; Gilkerson, Robert

    2015-06-01

    Human mitochondrial DNA (mtDNA) is a small maternally inherited DNA, typically present in hundreds of copies in a single human cell. Thus, despite its small size, the mitochondrial genome plays a crucial role in the metabolic homeostasis of the cell. Our understanding of mtDNA genotype-phenotype relationships is derived largely from studies of the classical mitochondrial neuromuscular diseases, in which mutations of mtDNA lead to compromised mitochondrial bioenergetic function, with devastating pathological consequences. Emerging research suggests that loss, rather than mutation, of mtDNA plays a major role across a range of prevalent human diseases, including diabetes mellitus, cardiovascular disease, and aging. Here, we examine the 'rules' of mitochondrial genetics and function, the clinical settings in which loss of mtDNA is an emerging pathogenic mechanism, and explore mtDNA damage and its consequences for the organellar network and cell at large. As extranuclear genetic material arrayed throughout the cell to support metabolism, mtDNA is increasingly implicated in a host of disease conditions, opening a range of exciting questions regarding mtDNA and its role in cellular homeostasis.

  16. The current status of studies on mitochondrial DNA with tumor, radiation biological effects and aging

    International Nuclear Information System (INIS)

    Liu Qingjie; Sang Lu

    2004-01-01

    The mitochondrial plays a very important role in sustaining the normal physiological function, because it is the center of energy making and mitochondrial DNA (mtDNA) is the only genetic material outside the nuclear. The result of studies showed that many diseases have a close relationship with mtDNA mutation and deletion. This article reviewed the current status of research on mtDNA with tumor, radiation biological effects and aging, in order to initiate the application study of mtDNA in the circle of radiation medicine

  17. The potential role for use of mitochondrial DNA copy number as predictive biomarker in presbycusis.

    Science.gov (United States)

    Falah, Masoumeh; Houshmand, Massoud; Najafi, Mohammad; Balali, Maryam; Mahmoudian, Saeid; Asghari, Alimohamad; Emamdjomeh, Hessamaldin; Farhadi, Mohammad

    2016-01-01

    Age-related hearing impairment, or presbycusis, is the most common communication disorder and neurodegenerative disease in the elderly. Its prevalence is expected to increase, due to the trend of growth of the elderly population. The current diagnostic test for detection of presbycusis is implemented after there has been a change in hearing sensitivity. Identification of a pre-diagnostic biomarker would raise the possibility of preserving hearing sensitivity before damage occurs. Mitochondrial dysfunction, including the production of reactive oxygen species and induction of expression of apoptotic genes, participates in the progression of presbycusis. Mitochondrial DNA sequence variation has a critical role in presbycusis. However, the nature of the relationship between mitochondrial DNA copy number, an important biomarker in many other diseases, and presbycusis is undetermined. Fifty-four subjects with presbycusis and 29 healthy controls were selected after ear, nose, throat examination and pure-tone audiometry. DNA was extracted from peripheral blood samples. The copy number of mitochondrial DNA relative to the nuclear genome was measured by quantitative real-time polymerase chain reaction. Subjects with presbycusis had a lower median mitochondrial DNA copy number than healthy subjects and the difference was statistically significant ( P =0.007). Mitochondrial DNA copy number was also significantly associated with degree of hearing impairment ( P =0.025) and audiogram configuration ( P =0.022). The findings of this study suggest that lower mitochondrial DNA copy number is responsible for presbycusis through alteration of mitochondrial function. Moreover, the significant association of mitochondrial DNA copy number in peripheral blood samples with the degree of hearing impairment and audiogram configuration has potential for use as a standard test for presbycusis, providing the possibility of the development of an easy-to-use biomarker for the early detection of

  18. The importance of mitochondrial DNA in aging and cancer

    DEFF Research Database (Denmark)

    Madsen, Claus Desler; Espersen, Maiken Lise Marcker; Singh, Keshav K

    2011-01-01

    Mitochondrial dysfunction has been implicated in premature aging, age-related diseases, and tumor initiation and progression. Alterations of the mitochondrial genome accumulate both in aging tissue and tumors. This paper describes our contemporary view of mechanisms by which alterations...... of the mitochondrial genome contributes to the development of age- and tumor-related pathological conditions. The mechanisms described encompass altered production of mitochondrial ROS, altered regulation of the nuclear epigenome, affected initiation of apoptosis, and a limiting effect on the production...

  19. Fidelity and mutational spectrum of Pfu DNA polymerase on a human mitochondrial DNA sequence.

    Science.gov (United States)

    André, P; Kim, A; Khrapko, K; Thilly, W G

    1997-08-01

    The study of rare genetic changes in human tissues requires specialized techniques. Point mutations at fractions at or below 10(-6) must be observed to discover even the most prominent features of the point mutational spectrum. PCR permits the increase in number of mutant copies but does so at the expense of creating many additional mutations or "PCR noise". Thus, each DNA sequence studied must be characterized with regard to the DNA polymerase and conditions used to avoid interpreting a PCR-generated mutation as one arising in human tissue. The thermostable DNA polymerase derived from Pyrococcus furiosus designated Pfu has the highest fidelity of any DNA thermostable polymerase studied to date, and this property recommends it for analyses of tissue mutational spectra. Here, we apply constant denaturant capillary electrophoresis (CDCE) to separate and isolate the products of DNA amplification. This new strategy permitted direct enumeration and identification of point mutations created by Pfu DNA polymerase in a 96-bp low melting domain of a human mitochondrial sequence despite the very low mutant fractions generated in the PCR process. This sequence, containing part of the tRNA glycine and NADH dehydrogenase subunit 3 genes, is the target of our studies of mitochondrial mutagenesis in human cells and tissues. Incorrectly synthesized sequences were separated from the wild type as mutant/wild-type heteroduplexes by sequential enrichment on CDCE. An artificially constructed mutant was used as an internal standard to permit calculation of the mutant fraction. Our study found that the average error rate (mutations per base pair duplication) of Pfu was 6.5 x 10(-7), and five of its more frequent mutations (hot spots) consisted of three transversions (GC-->TA, AT-->TA, and AT-->CG), one transition (AT-->GC), and one 1-bp deletion (in an AAAAAA sequence). To achieve an even higher sensitivity, the amount of Pfu-induced mutants must be reduced.

  20. Psychiatric symptoms of patients with primary mitochondrial DNA disorders

    Directory of Open Access Journals (Sweden)

    Inczedy-Farkas Gabriella

    2012-02-01

    Full Text Available Abstract Background The aim of our study was to assess psychiatric symptoms in patients with genetically proven primary mutation of the mitochondrial DNA. Methods 19 adults with known mitochondrial mutation (MT have been assessed with the Stanford Health Assessment Questionnaire 20-item Disability Index (HAQ-DI, the Symptom Check List-90-Revised (SCL-90-R, the Beck Depression Inventory-Short Form (BDI-SF, the Hamilton Depression Rating Scale (HDRS and the clinical version of the Structured Clinical Interview for the the DSM-IV (SCID-I and SCID-II As control, 10 patients with hereditary sensorimotor neuropathy (HN, harboring the peripheral myelin protein-22 (PMP22 mutation were examined with the same tools. Results The two groups did not differ significantly in gender, age or education. Mean HAQ-DI score was 0.82 in the MT (range: 0-1.625 and 0.71 in the HN group (range: 0-1.625. Level of disability between the two groups did not differ significantly (p = 0.6076. MT patients scored significantly higher on the BDI-SF and HDRS than HN patients (12.85 versus 4.40, p = 0.031, and 15.62 vs 7.30, p = 0.043, respectively. The Global Severity Index (GSI of SCL-90-R also showed significant difference (1.44 vs 0.46, p = 0.013 as well as the subscales except for somatization. SCID-I interview yielded a variety of mood disorders in both groups. Eight MT patient (42% had past, 6 (31% had current, 5 (26% had both past and current psychiatric diagnosis, yielding a lifetime prevalence of 9/19 (47% in the MT group. In the HN group, 3 patients had both past and current diagnosis showing a lifetime prevalence of 3/10 (30% in this group. SCID-II detected personality disorder in 8 MT cases (42%, yielding 3 avoidant, 2 obsessive-compulsive and 3 personality disorder not otherwise specified (NOS diagnosis. No personality disorder was identified in the HN group. Conclusions Clinicians should be aware of the high prevalence of psychiatric symptoms in patients with

  1. A revised timescale for human evolution based on ancient mitochondrial genomes

    Czech Academy of Sciences Publication Activity Database

    Fu, Q.; Mittnik, A.; Johnson, P. L. F.; Bos, K.; Lari, M.; Bollongino, R.; Sun, Ch.; Giemsch, L.; Schmitz, R.; Burger, J.; Ronchitelli, A. M.; Martini, F.; Cremonesi, R. G.; Svoboda, Jiří; Bauer, P.; Caramelli, D.; Castellano, S.; Reich, D.; Pääbo, S.; Krause, J.

    2013-01-01

    Roč. 23, April 8 (2013), s. 553-559 ISSN 0960-9822 Institutional support: RVO:68081758 Keywords : mitochondrial genome * human evolution * calibration Subject RIV: AC - Archeology, Anthropology, Ethnology OBOR OECD: Archaeology Impact factor: 9.916, year: 2013

  2. Nuclear transfer to prevent mitochondrial DNA disorders : revisiting the debate on reproductive cloning

    NARCIS (Netherlands)

    Bredenoord, A. L.; Dondorp, W.; Pennings, G.; De Wert, G.

    Preclinical experiments are currently performed to examine the feasibility of several types of nuclear transfer to prevent mitochondrial DNA (mtDNA) disorders. Whereas the two most promising types of nuclear transfer to prevent mtDNA disorders, spindle transfer and pronuclear transfer, do not amount

  3. Heterology of mitochondrial DNA from mammals detected by electron microscopic heteroduplex analyses

    DEFF Research Database (Denmark)

    Christiansen, Gunna; Christiansen, C

    1983-01-01

    Heteroduplex analysis of mitochondrial DNA (mtDNA) from evolutionary closely related mammals (rat vs. mouse, man vs. monkey) are analyzed and compared to heteroduplex analysis of mt-DNA from more distantly related mammals (rat vs. man, rat vs. monkey, mouse vs. man, mouse vs. monkey and man vs. c...

  4. The interplay between SUCLA2, SUCLG2, and mitochondrial DNA depletion

    DEFF Research Database (Denmark)

    Miller, Chaya; Wang, Liya; Ostergaard, Elsebet

    2011-01-01

    SUCLA2-related mitochondrial DNA (mtDNA) depletion syndrome is a result of mutations in the β subunit of the ADP-dependent isoform of the Krebs cycle succinyl-CoA synthase (SCS). The mechanism of tissue specificity and mtDNA depletion is elusive but complementation by the GDP-dependent isoform en...

  5. Distinct structural features of TFAM drive mitochondrial DNA packaging versus transcriptional activation.

    Science.gov (United States)

    Ngo, Huu B; Lovely, Geoffrey A; Phillips, Rob; Chan, David C

    2014-01-01

    TFAM (transcription factor A, mitochondrial) is a DNA-binding protein that activates transcription at the two major promoters of mitochondrial DNA (mtDNA)--the light strand promoter (LSP) and the heavy strand promoter 1 (HSP1). Equally important, it coats and packages the mitochondrial genome. TFAM has been shown to impose a U-turn on LSP DNA; however, whether this distortion is relevant at other sites is unknown. Here we present crystal structures of TFAM bound to HSP1 and to nonspecific DNA. In both, TFAM similarly distorts the DNA into a U-turn. Yet, TFAM binds to HSP1 in the opposite orientation from LSP explaining why transcription from LSP requires DNA bending, whereas transcription at HSP1 does not. Moreover, the crystal structures reveal dimerization of DNA-bound TFAM. This dimerization is dispensable for DNA bending and transcriptional activation but is important in DNA compaction. We propose that TFAM dimerization enhances mitochondrial DNA compaction by promoting looping of the DNA.

  6. Biomolecular identification of ancient Mycobacterium tuberculosis complex DNA in human remains from Britain and continental Europe.

    Science.gov (United States)

    Müller, Romy; Roberts, Charlotte A; Brown, Terence A

    2014-02-01

    Tuberculosis is known to have afflicted humans throughout history and re-emerged towards the end of the 20th century, to an extent that it was declared a global emergency in 1993. The aim of this study was to apply a rigorous analytical regime to the detection of Mycobacterium tuberculosis complex (MTBC) DNA in 77 bone and tooth samples from 70 individuals from Britain and continental Europe, spanning the 1st-19th centuries AD. We performed the work in dedicated ancient DNA facilities designed to prevent all types of modern contamination, we checked the authenticity of all products obtained by the polymerase chain reaction, and we based our conclusions on up to four replicate experiments for each sample, some carried out in an independent laboratory. We identified 12 samples that, according to our strict criteria, gave definite evidence for the presence of MTBC DNA, and another 22 that we classified as "probable" or "possible." None of the definite samples came from vertebrae displaying lesions associated with TB. Instead, eight were from ribs displaying visceral new bone formation, one was a tooth from a skeleton with rib lesions, one was taken from a skeleton with endocranial lesions, one from an individual with lesions to the sacrum and sacroiliac joint and the last was from an individual with no lesions indicative of TB or possible TB. Our results add to information on the past temporal and geographical distribution of TB and affirm the suitability of ribs for studying ancient TB. Copyright © 2013 Wiley Periodicals, Inc.

  7. Ancient DNA reveals genetic connections between early Di-Qiang and Han Chinese.

    Science.gov (United States)

    Li, Jiawei; Zeng, Wen; Zhang, Ye; Ko, Albert Min-Shan; Li, Chunxiang; Zhu, Hong; Fu, Qiaomei; Zhou, Hui

    2017-12-04

    Ancient Di-Qiang people once resided in the Ganqing region of China, adjacent to the Central Plain area from where Han Chinese originated. While gene flow between the Di-Qiang and Han Chinese has been proposed, there is no evidence to support this view. Here we analyzed the human remains from an early Di-Qiang site (Mogou site dated ~4000 years old) and compared them to other ancient DNA across China, including an early Han-related site (Hengbei site dated ~3000 years old) to establish the underlying genetic relationship between the Di-Qiang and ancestors of Han Chinese. We found Mogou mtDNA haplogroups were highly diverse, comprising 14 haplogroups: A, B, C, D (D*, D4, D5), F, G, M7, M8, M10, M13, M25, N*, N9a, and Z. In contrast, Mogou males were all Y-DNA haplogroup O3a2/P201; specifically one male was further assigned to O3a2c1a/M117 using targeted unique regions on the non-recombining region of the Y-chromosome. We compared Mogou to 7 other ancient and 38 modern Chinese groups, in a total of 1793 individuals, and found that Mogou shared close genetic distances with Taojiazhai (a more recent Di-Qiang population), Hengbei, and Northern Han. We modeled their interactions using Approximate Bayesian Computation, and support was given to a potential admixture of ~13-18% between the Mogou and Northern Han around 3300-3800 years ago. Mogou harbors the earliest genetically identifiable Di-Qiang, ancestral to the Taojiazhai, and up to ~33% paternal and ~70% of its maternal haplogroups could be found in present-day Northern Han Chinese.

  8. Bona fide colour: DNA prediction of human eye and hair colour from ancient and contemporary skeletal remains

    NARCIS (Netherlands)

    J. Draus-Barini (Jolanta); S. Walsh (Susan); E. Pośpiech (Ewelina); T. Kupiec (Tomasz); H. Głab (Henryk); W. Branicki (Wojciech); M.H. Kayser (Manfred)

    2013-01-01

    textabstractBackground: DNA analysis of ancient skeletal remains is invaluable in evolutionary biology for exploring the history of species, including humans. Contemporary human bones and teeth, however, are relevant in forensic DNA analyses that deal with the identification of perpetrators, missing

  9. Cockayne syndrome group B protein promotes mitochondrial DNA stability by supporting the DNA repair association with the mitochondrial membrane

    DEFF Research Database (Denmark)

    Aamann, Maria Diget; Sorensen, Martin M; Hvitby, Christina Poulsen

    2010-01-01

    in genomic maintenance and transcriptome regulation. By immunocytochemistry, mitochondrial fractionation, and Western blotting, we demonstrate that CSB localizes to mitochondria in different types of cells, with increased mitochondrial distribution following menadione-induced oxidative stress. Moreover, our...

  10. A role for recombination junctions in the segregation of mitochondrial DNA in yeast.

    Science.gov (United States)

    Lockshon, D; Zweifel, S G; Freeman-Cook, L L; Lorimer, H E; Brewer, B J; Fangman, W L

    1995-06-16

    In S. cerevisiae, mitochondrial DNA (mtDNA) molecules, in spite of their high copy number, segregate as if there were a small number of heritable units. The rapid segregation of mitochondrial genomes can be analyzed using mtDNA deletion variants. These small, amplified genomes segregate preferentially from mixed zygotes relative to wild-type mtDNA. This segregation advantage is abolished by mutations in a gene, MGT1, that encodes a recombination junction-resolving enzyme. We show here that resolvase deficiency causes a larger proportion of molecules to be linked together by recombination junctions, resulting in the aggregation of mtDNA into a small number of cytological structures. This change in mtDNA structure can account for the increased mitotic loss of mtDNA and the altered pattern of mtDNA segregation from zygotes. We propose that the level of unresolved recombination junctions influences the number of heritable units of mtDNA.

  11. Roche genome sequencer FLX based high-throughput sequencing of ancient DNA

    DEFF Research Database (Denmark)

    Alquezar-Planas, David E; Fordyce, Sarah Louise

    2012-01-01

    Since the development of so-called "next generation" high-throughput sequencing in 2005, this technology has been applied to a variety of fields. Such applications include disease studies, evolutionary investigations, and ancient DNA. Each application requires a specialized protocol to ensure...... that the data produced is optimal. Although much of the procedure can be followed directly from the manufacturer's protocols, the key differences lie in the library preparation steps. This chapter presents an optimized protocol for the sequencing of fossil remains and museum specimens, commonly referred...

  12. Ancient DNA from lake sediments: Bridging the gap between paleoecology and genetics

    Directory of Open Access Journals (Sweden)

    Lumibao Candice Y

    2011-01-01

    Full Text Available Abstract Background Quaternary plant ecology in much of the world has historically relied on morphological identification of macro- and microfossils from sediments of small freshwater lakes. Here, we report new protocols that reliably yield DNA sequence data from Holocene plant macrofossils and bulk lake sediment used to infer ecological change. This will allow changes in census populations, estimated from fossils and associated sediment, to be directly associated with population genetic changes. Results We successfully sequenced DNA from 64 samples (out of 126 comprised of bulk sediment and seeds, leaf fragments, budscales, and samaras extracted from Holocene lake sediments in the western Great Lakes region of North America. Overall, DNA yields were low. However, we were able to reliably amplify samples with as few as 10 copies of a short cpDNA fragment with little detectable PCR inhibition. Our success rate was highest for sediments Conclusions An ability to extract ancient DNA from Holocene sediments potentially allows exciting new insights into the genetic consequences of long-term environmental change. The low DNA copy numbers we found in fossil material and the discovery of multiple sequence variants from single macrofossil extractions highlight the need for careful experimental and laboratory protocols. Further application of these protocols should lead to better understanding of the ecological and evolutionary consequences of environmental change.

  13. Phylogeny of the Serrasalmidae (Characiformes based on mitochondrial DNA sequences

    Directory of Open Access Journals (Sweden)

    Guillermo Ortí

    2008-01-01

    Full Text Available Previous studies based on DNA sequences of mitochondrial (mt rRNA genes showed three main groups within the subfamily Serrasalminae: (1 a "pacu" clade of herbivores (Colossoma, Mylossoma, Piaractus; (2 the "Myleus" clade (Myleus, Mylesinus, Tometes, Ossubtus; and (3 the "piranha" clade (Serrasalmus, Pygocentrus, Pygopristis, Pristobrycon, Catoprion, Metynnis. The genus Acnodon was placed as the sister taxon of clade (2+3. However, poor resolution within each clade was obtained due to low levels of variation among rRNA gene sequences. Complete sequences of the hypervariable mtDNA control region for a total of 45 taxa, and additional sequences of 12S and 16S rRNA from a total of 74 taxa representing all genera in the family are now presented to address intragroup relationships. Control region sequences of several serrasalmid species exhibit tandem repeats of short motifs (12 to 33 bp in the 3' end of this region, accounting for substantial length variation. Bayesian inference and maximum parsimony analyses of these sequences identify the same groupings as before and provide further evidence to support the following observations: (a Serrasalmus gouldingi and species of Pristobrycon (non-striolatus form a monophyletic group that is the sister group to other species of Serrasalmus and Pygocentrus; (b Catoprion, Pygopristis, and Pristobrycon striolatus form a well supported clade, sister to the group described above; (c some taxa assigned to the genus Myloplus (M. asterias, M tiete, M ternetzi, and M rubripinnis form a well supported group whereas other Myloplus species remain with uncertain affinities (d Mylesinus, Tometes and Myleus setiger form a monophyletic group.

  14. Use of ancient sedimentary DNA as a novel conservation tool for high-altitude tropical biodiversity.

    Science.gov (United States)

    Boessenkool, Sanne; McGlynn, Gayle; Epp, Laura S; Taylor, David; Pimentel, Manuel; Gizaw, Abel; Nemomissa, Sileshi; Brochmann, Christian; Popp, Magnus

    2014-04-01

    Conservation of biodiversity may in the future increasingly depend upon the availability of scientific information to set suitable restoration targets. In traditional paleoecology, sediment-based pollen provides a means to define preanthropogenic impact conditions, but problems in establishing the exact provenance and ecologically meaningful levels of taxonomic resolution of the evidence are limiting. We explored the extent to which the use of sedimentary ancient DNA (sedaDNA) may complement pollen data in reconstructing past alpine environments in the tropics. We constructed a record of afro-alpine plants retrieved from DNA preserved in sediment cores from 2 volcanic crater sites in the Albertine Rift, eastern Africa. The record extended well beyond the onset of substantial anthropogenic effects on tropical mountains. To ensure high-quality taxonomic inference from the sedaDNA sequences, we built an extensive DNA reference library covering the majority of the afro-alpine flora, by sequencing DNA from taxonomically verified specimens. Comparisons with pollen records from the same sediment cores showed that plant diversity recovered with sedaDNA improved vegetation reconstructions based on pollen records by revealing both additional taxa and providing increased taxonomic resolution. Furthermore, combining the 2 measures assisted in distinguishing vegetation change at different geographic scales; sedaDNA almost exclusively reflects local vegetation, whereas pollen can potentially originate from a wide area that in highlands in particular can span several ecozones. Our results suggest that sedaDNA may provide information on restoration targets and the nature and magnitude of human-induced environmental changes, including in high conservation priority, biodiversity hotspots, where understanding of preanthropogenic impact (or reference) conditions is highly limited. © 2013 Society for Conservation Biology.

  15. Implementation of DNA mitochondrial analysis in rhinoclemmys nasuta (Testudines: Geoemydidae)

    International Nuclear Information System (INIS)

    Molina Henao, Yherson Franchesco; Barreto, Guillermo; Giraldo, Alan

    2014-01-01

    Rhinoclemmys nasuta (Testudines: geoemydidae) is considered an almost endemic specie to Colombia and the most primitive species of rhynoclemmys. However, it is classified data deficient by iucn because the available information is not enough to make a direct or indirect assessment of its extinction risk. Here, we describe the implementation of the method to analyze the mitochondrial DNA control sequence (mtdna) of R. nasuta in order to generate tools for future studies in systematics and population conservation. Genomic MTDNA was extracted by salting-out from blood samples from Isla Palma and Playa Chucheros (Bahia Malaga Colombian Pacific Coast) and we used a pair of degenerate primers (reported for chrysemys picta, testudines: emydidae) to perform amplification. Fragments of 800pb were obtained and the sequencing reaction was effective. A homology percentage above of 92 % was established between the obtained sequences and MTDNA sequences from Sacalia quadriocellata (Testudines: geoemydidae), and Cuora aurocapitata (Testudines: geoemydidae) reported in the genbank. This result shows that the described method can be a useful tool for the study of R. nasuta populations in the Colombian pacific region, achieving an effective sequencing of the MTDNA control region of this species.

  16. The Role of Mitochondrial DNA in Mediating Alveolar Epithelial Cell Apoptosis and Pulmonary Fibrosis

    Science.gov (United States)

    Kim, Seok-Jo; Cheresh, Paul; Jablonski, Renea P.; Williams, David B.; Kamp, David W.

    2015-01-01

    Convincing evidence has emerged demonstrating that impairment of mitochondrial function is critically important in regulating alveolar epithelial cell (AEC) programmed cell death (apoptosis) that may contribute to aging-related lung diseases, such as idiopathic pulmonary fibrosis (IPF) and asbestosis (pulmonary fibrosis following asbestos exposure). The mammalian mitochondrial DNA (mtDNA) encodes for 13 proteins, including several essential for oxidative phosphorylation. We review the evidence implicating that oxidative stress-induced mtDNA damage promotes AEC apoptosis and pulmonary fibrosis. We focus on the emerging role for AEC mtDNA damage repair by 8-oxoguanine DNA glycosylase (OGG1) and mitochondrial aconitase (ACO-2) in maintaining mtDNA integrity which is important in preventing AEC apoptosis and asbestos-induced pulmonary fibrosis in a murine model. We then review recent studies linking the sirtuin (SIRT) family members, especially SIRT3, to mitochondrial integrity and mtDNA damage repair and aging. We present a conceptual model of how SIRTs modulate reactive oxygen species (ROS)-driven mitochondrial metabolism that may be important for their tumor suppressor function. The emerging insights into the pathobiology underlying AEC mtDNA damage and apoptosis is suggesting novel therapeutic targets that may prove useful for the management of age-related diseases, including pulmonary fibrosis and lung cancer. PMID:26370974

  17. Fructose-Rich Diet Affects Mitochondrial DNA Damage and Repair in Rats.

    Science.gov (United States)

    Cioffi, Federica; Senese, Rosalba; Lasala, Pasquale; Ziello, Angela; Mazzoli, Arianna; Crescenzo, Raffaella; Liverini, Giovanna; Lanni, Antonia; Goglia, Fernando; Iossa, Susanna

    2017-03-24

    Evidence indicates that many forms of fructose-induced metabolic disturbance are associated with oxidative stress and mitochondrial dysfunction. Mitochondria are prominent targets of oxidative damage; however, it is not clear whether mitochondrial DNA (mtDNA) damage and/or its lack of repair are events involved in metabolic disease resulting from a fructose-rich diet. In the present study, we evaluated the degree of oxidative damage to liver mtDNA and its repair, in addition to the state of oxidative stress and antioxidant defense in the liver of rats fed a high-fructose diet. We used male rats feeding on a high-fructose or control diet for eight weeks. Our results showed an increase in mtDNA damage in the liver of rats fed a high-fructose diet and this damage, as evaluated by the expression of DNA polymerase γ, was not repaired; in addition, the mtDNA copy number was found to be significantly reduced. A reduction in the mtDNA copy number is indicative of impaired mitochondrial biogenesis, as is the finding of a reduction in the expression of genes involved in mitochondrial biogenesis. In conclusion, a fructose-rich diet leads to mitochondrial and mtDNA damage, which consequently may have a role in liver dysfunction and metabolic diseases.

  18. Ancient DNA analysis suggests negligible impact of the Wari Empire expansion in Peru's central coast during the Middle Horizon

    OpenAIRE

    Valverde, G.; Romero, M.; Espinoza, I.; Cooper, A.; Fehren-Schmitz, L.; Llamas, B.; Haak, W.

    2016-01-01

    The analysis of ancient human DNA from South America allows the exploration of pre-Columbian population history through time and to directly test hypotheses about cultural and demographic evolution. The Middle Horizon (650?1100 AD) represents a major transitional period in the Central Andes, which is associated with the development and expansion of ancient Andean empires such as Wari and Tiwanaku. These empires facilitated a series of interregional interactions and socio-political changes, wh...

  19. Complex forms of mitochondrial DNA in human B cells transformed by Epstein-Barr virus (EBV)

    DEFF Research Database (Denmark)

    Christiansen, Gunna; Christiansen, C; Zeuthen, J

    1983-01-01

    Human lymphocytes and lymphoid cell lines were analyzed for the presence of complex forms of mitochondrial DNA (mtDNA) by electron microscopy. A high frequency (9%-14.5%) of catenated dimers, circular dimers, or oligomers were found in samples from Epstein-Barr-virus-(EBV) transformed lymphoblast......Human lymphocytes and lymphoid cell lines were analyzed for the presence of complex forms of mitochondrial DNA (mtDNA) by electron microscopy. A high frequency (9%-14.5%) of catenated dimers, circular dimers, or oligomers were found in samples from Epstein-Barr-virus-(EBV) transformed...

  20. Complete mtDNA genomes of Filipino ethnolinguistic groups: a melting pot of recent and ancient lineages in the Asia-Pacific region

    Science.gov (United States)

    Delfin, Frederick; Min-Shan Ko, Albert; Li, Mingkun; Gunnarsdóttir, Ellen D; Tabbada, Kristina A; Salvador, Jazelyn M; Calacal, Gayvelline C; Sagum, Minerva S; Datar, Francisco A; Padilla, Sabino G; De Ungria, Maria Corazon A; Stoneking, Mark

    2014-01-01

    The Philippines is a strategic point in the Asia-Pacific region for the study of human diversity, history and origins, as it is a cross-road for human migrations and consequently exhibits enormous ethnolinguistic diversity. Following on a previous in-depth study of Y-chromosome variation, here we provide new insights into the maternal genetic history of Filipino ethnolinguistic groups by surveying complete mitochondrial DNA (mtDNA) genomes from a total of 14 groups (11 groups in this study and 3 groups previously published) including previously published mtDNA hypervariable segment (HVS) data from Filipino regional center groups. Comparison of HVS data indicate genetic differences between ethnolinguistic and regional center groups. The complete mtDNA genomes of 14 ethnolinguistic groups reveal genetic aspects consistent with the Y-chromosome, namely: diversity and heterogeneity of groups, no support for a simple dichotomy between Negrito and non-Negrito groups, and different genetic affinities with Asia-Pacific groups that are both ancient and recent. Although some mtDNA haplogroups can be associated with the Austronesian expansion, there are others that associate with South Asia, Near Oceania and Australia that are consistent with a southern migration route for ethnolinguistic group ancestors into the Asia-Pacific, with a timeline that overlaps with the initial colonization of the Asia-Pacific region, the initial colonization of the Philippines and a possible separate post-colonization migration into the Philippine archipelago. PMID:23756438

  1. Thymidine kinase 2 enzyme kinetics elucidate the mechanism of thymidine-induced mitochondrial DNA depletion.

    Science.gov (United States)

    Sun, Ren; Wang, Liya

    2014-10-07

    Mitochondrial thymidine kinase 2 (TK2) is a nuclear gene-encoded protein, synthesized in the cytosol and subsequently translocated into the mitochondrial matrix, where it catalyzes the phosphorylation of thymidine (dT) and deoxycytidine (dC). The kinetics of dT phosphorylation exhibits negative cooperativity, but dC phosphorylation follows hyperbolic Michaelis-Menten kinetics. The two substrates compete with each other in that dT is a competitive inhibitor of dC phosphorylation, while dC acts as a noncompetitive inhibitor of dT phosphorylation. In addition, TK2 is feedback inhibited by dTTP and dCTP. TK2 also phosphorylates a number of pyrimidine nucleoside analogues used in antiviral and anticancer therapy and thus plays an important role in mitochondrial toxicities caused by nucleoside analogues. Deficiency in TK2 activity due to genetic alterations causes devastating mitochondrial diseases, which are characterized by mitochondrial DNA (mtDNA) depletion or multiple deletions in the affected tissues. Severe TK2 deficiency is associated with early-onset fatal mitochondrial DNA depletion syndrome, while less severe deficiencies result in late-onset phenotypes. In this review, studies of the enzyme kinetic behavior of TK2 enzyme variants are used to explain the mechanism of mtDNA depletion caused by TK2 mutations, thymidine overload due to thymidine phosphorylase deficiency, and mitochondrial toxicity caused by antiviral thymidine analogues.

  2. Neanderthal behaviour, diet, and disease inferred from ancient DNA in dental calculus.

    Science.gov (United States)

    Weyrich, Laura S; Duchene, Sebastian; Soubrier, Julien; Arriola, Luis; Llamas, Bastien; Breen, James; Morris, Alan G; Alt, Kurt W; Caramelli, David; Dresely, Veit; Farrell, Milly; Farrer, Andrew G; Francken, Michael; Gully, Neville; Haak, Wolfgang; Hardy, Karen; Harvati, Katerina; Held, Petra; Holmes, Edward C; Kaidonis, John; Lalueza-Fox, Carles; de la Rasilla, Marco; Rosas, Antonio; Semal, Patrick; Soltysiak, Arkadiusz; Townsend, Grant; Usai, Donatella; Wahl, Joachim; Huson, Daniel H; Dobney, Keith; Cooper, Alan

    2017-04-20

    Recent genomic data have revealed multiple interactions between Neanderthals and modern humans, but there is currently little genetic evidence regarding Neanderthal behaviour, diet, or disease. Here we describe the shotgun-sequencing of ancient DNA from five specimens of Neanderthal calcified dental plaque (calculus) and the characterization of regional differences in Neanderthal ecology. At Spy cave, Belgium, Neanderthal diet was heavily meat based and included woolly rhinoceros and wild sheep (mouflon), characteristic of a steppe environment. In contrast, no meat was detected in the diet of Neanderthals from El Sidrón cave, Spain, and dietary components of mushrooms, pine nuts, and moss reflected forest gathering. Differences in diet were also linked to an overall shift in the oral bacterial community (microbiota) and suggested that meat consumption contributed to substantial variation within Neanderthal microbiota. Evidence for self-medication was detected in an El Sidrón Neanderthal with a dental abscess and a chronic gastrointestinal pathogen (Enterocytozoon bieneusi). Metagenomic data from this individual also contained a nearly complete genome of the archaeal commensal Methanobrevibacter oralis (10.2× depth of coverage)-the oldest draft microbial genome generated to date, at around 48,000 years old. DNA preserved within dental calculus represents a notable source of information about the behaviour and health of ancient hominin specimens, as well as a unique system that is useful for the study of long-term microbial evolution.

  3. Toward a new history and geography of human genes informed by ancient DNA.

    Science.gov (United States)

    Pickrell, Joseph K; Reich, David

    2014-09-01

    Genetic information contains a record of the history of our species, and technological advances have transformed our ability to access this record. Many studies have used genome-wide data from populations today to learn about the peopling of the globe and subsequent adaptation to local conditions. Implicit in this research is the assumption that the geographic locations of people today are informative about the geographic locations of their ancestors in the distant past. However, it is now clear that long-range migration, admixture, and population replacement subsequent to the initial out-of-Africa expansion have altered the genetic structure of most of the world's human populations. In light of this we argue that it is time to critically reevaluate current models of the peopling of the globe, as well as the importance of natural selection in determining the geographic distribution of phenotypes. We specifically highlight the transformative potential of ancient DNA. By accessing the genetic make-up of populations living at archaeologically known times and places, ancient DNA makes it possible to directly track migrations and responses to natural selection. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Optical dating of perennially frozen deposits associated with preserved ancient plant and animal DNA in north-central Siberia

    DEFF Research Database (Denmark)

    Arnold, L.J.; Roberts, R.G.; Macphee, R.D.E.

    2008-01-01

    We present chronological constraints on a suite of permanently frozen fluvial deposits which contain ancient DNA (aDNA) from the Taimyr Peninsula of north-central Siberia. The luminescence phenomenology of these samples is first discussed, focusing on the optically stimulated luminescence (OSL) d...... of providing a reliable chronometric framework for sedimentary aDNA records in permafrost environments. (C) 2007 Elsevier Ltd. All rights reserved Udgivelsesdato: 2008...

  5. Differential chromosomal and mitochondrial DNA synthesis in temperature-sensitive mutants of Ustilago maydis

    Energy Technology Data Exchange (ETDEWEB)

    Unrau, P.

    1977-01-01

    The amount and type of residual DNA synthesis was determined in eight temperature-sensitive mutants of the smut fungus Ustilago maydis after incubation at the restrictive temperature (32/sup 0/C) for eight hours. Mutants ts-220, ts-207, ts-432 and ts-346 were found to have an overall reduction in the synthesis of both nuclear and mitochondrial DNA in comparison to the wild-type. In mutants ts-20, tsd 1-1, ts-84 and pol 1-1 nuclear DNA synthesis was depressed relative to mitochondrial synthesis. The DNA-polymerase mutant pol 1-1 had persistent nuclear synthesis at about 50% of the rate of synthesis of mitochondrial DNA and similar behavior was observed in a diploid homozygous strain. Mutant ts-84 had an initial burst of DNA synthesis which was reduced for nuclear but not mitochondrial synthesis after three hours preincubation at 32/sup 0/C. tsd 1-1 and ts-20 had nuclear residual synthesis amounting to about 25% of the relative rate of mitochondrial synthesis which correlates to increasing UV sensitivity of these strains on incubation at 32/sup 0/C. A pol 1-1 ts-84 double mutant had an additive loss of nuclear DNA synthesis which indicates that the steps of replication involved may be sequential.

  6. Adult cases of mitochondrial DNA depletion due to TK2 defect: an expanding spectrum.

    Science.gov (United States)

    Béhin, A; Jardel, C; Claeys, K G; Fagart, J; Louha, M; Romero, N B; Laforêt, P; Eymard, B; Lombès, A

    2012-02-28

    In this study we aim to demonstrate the occurrence of adult forms of TK2 mutations causing progressive mitochondrial myopathy with significant muscle mitochondrial DNA (mtDNA) depletion. Patients' investigations included serum creatine kinase, blood lactate, electromyographic, echocardiographic, and functional respiratory analyses as well as TK2 gene sequencing and TK2 activity measurement. Mitochondrial activities and mtDNA were analyzed in the patients' muscle biopsy. The 3 adult patients with TK2 mutations presented with slowly progressive myopathy compatible with a fairly normal life during decades. Apart from its much slower progression, these patients' phenotype closely resembled that of pediatric cases including early onset, absence of CNS symptoms, generalized muscle weakness predominating on axial and proximal muscles but affecting facial, ocular, and respiratory muscles, typical mitochondrial myopathy with a mosaic pattern of COX-negative and ragged-red fibers, combined mtDNA-dependent respiratory complexes deficiency and mtDNA depletion. In accordance with the disease's relatively slow progression, the residual mtDNA content was higher than that observed in pediatric cases. That difference was not explained by the type of the TK2 mutations or by the residual TK2 activity. TK2 mutations can cause mitochondrial myopathy with a slow progression. Comparison of patients with similar mutations but different disease progression might address potential mechanisms of mtDNA maintenance modulation.

  7. Mitochondrial Targeted Endonuclease III DNA Repair Enzyme Protects against Ventilator Induced Lung Injury in Mice

    Directory of Open Access Journals (Sweden)

    Masahiro Hashizume

    2014-08-01

    Full Text Available The mitochondrial targeted DNA repair enzyme, 8-oxoguanine DNA glycosylase 1, was previously reported to protect against mitochondrial DNA (mtDNA damage and ventilator induced lung injury (VILI. In the present study we determined whether mitochondrial targeted endonuclease III (EndoIII which cleaves oxidized pyrimidines rather than purines from damaged DNA would also protect the lung. Minimal injury from 1 h ventilation at 40 cmH2O peak inflation pressure (PIP was reversed by EndoIII pretreatment. Moderate lung injury due to ventilation for 2 h at 40 cmH2O PIP produced a 25-fold increase in total extravascular albumin space, a 60% increase in W/D weight ratio, and marked increases in MIP-2 and IL-6. Oxidative mtDNA damage and decreases in the total tissue glutathione (GSH and the GSH/GSSH ratio also occurred. All of these indices of injury were attenuated by mitochondrial targeted EndoIII. Massive lung injury caused by 2 h ventilation at 50 cmH2O PIP was not attenuated by EndoIII pretreatment, but all untreated mice died prior to completing the two hour ventilation protocol, whereas all EndoIII-treated mice lived for the duration of ventilation. Thus, mitochondrial targeted DNA repair enzymes were protective against mild and moderate lung damage and they enhanced survival in the most severely injured group.

  8. Blocking human contaminant DNA during PCR allows amplification of rare mammal species from sedimentary ancient DNA

    DEFF Research Database (Denmark)

    Boessenkool, Sanne; Epp, Laura S.; Haile, James Seymour

    2012-01-01

    the amplification of contaminant sequences to such an extent that retrieval of the endogenous DNA is severely restricted. The application of blocking primers is a promising tool to avoid this bias and can greatly enhance the quantity and the diversity of the endogenous DNA sequences that are amplified....

  9. Potential efficacy of mitochondrial genes for animal DNA barcoding: a case study using eutherian mammals.

    Science.gov (United States)

    Luo, Arong; Zhang, Aibing; Ho, Simon Yw; Xu, Weijun; Zhang, Yanzhou; Shi, Weifeng; Cameron, Stephen L; Zhu, Chaodong

    2011-01-28

    A well-informed choice of genetic locus is central to the efficacy of DNA barcoding. Current DNA barcoding in animals involves the use of the 5' half of the mitochondrial cytochrome oxidase 1 gene (CO1) to diagnose and delimit species. However, there is no compelling a priori reason for the exclusive focus on this region, and it has been shown that it performs poorly for certain animal groups. To explore alternative mitochondrial barcoding regions, we compared the efficacy of the universal CO1 barcoding region with the other mitochondrial protein-coding genes in eutherian mammals. Four criteria were used for this comparison: the number of recovered species, sequence variability within and between species, resolution to taxonomic levels above that of species, and the degree of mutational saturation. Based on 1,179 mitochondrial genomes of eutherians, we found that the universal CO1 barcoding region is a good representative of mitochondrial genes as a whole because the high species-recovery rate (> 90%) was similar to that of other mitochondrial genes, and there were no significant differences in intra- or interspecific variability among genes. However, an overlap between intra- and interspecific variability was still problematic for all mitochondrial genes. Our results also demonstrated that any choice of mitochondrial gene for DNA barcoding failed to offer significant resolution at higher taxonomic levels. We suggest that the CO1 barcoding region, the universal DNA barcode, is preferred among the mitochondrial protein-coding genes as a molecular diagnostic at least for eutherian species identification. Nevertheless, DNA barcoding with this marker may still be problematic for certain eutherian taxa and our approach can be used to test potential barcoding loci for such groups.

  10. Silencing of PINK1 expression affects mitochondrial DNA and oxidative phosphorylation in dopaminergic cells.

    Directory of Open Access Journals (Sweden)

    Matthew E Gegg

    Full Text Available Mitochondrial dysfunction has been implicated in the pathogenesis of Parkinson's disease (PD. Impairment of the mitochondrial electron transport chain (ETC and an increased frequency in deletions of mitochondrial DNA (mtDNA, which encodes some of the subunits of the ETC, have been reported in the substantia nigra of PD brains. The identification of mutations in the PINK1 gene, which cause an autosomal recessive form of PD, has supported mitochondrial involvement in PD. The PINK1 protein is a serine/threonine kinase localized in mitochondria and the cytosol. Its precise function is unknown, but it is involved in neuroprotection against a variety of stress signalling pathways.In this report we have investigated the effect of silencing PINK1 expression in human dopaminergic SH-SY5Y cells by siRNA on mtDNA synthesis and ETC function. Loss of PINK1 expression resulted in a decrease in mtDNA levels and mtDNA synthesis. We also report a concomitant loss of mitochondrial membrane potential and decreased mitochondrial ATP synthesis, with the activity of complex IV of the ETC most affected. This mitochondrial dysfunction resulted in increased markers of oxidative stress under basal conditions and increased cell death following treatment with the free radical generator paraquat.This report highlights a novel function of PINK1 in mitochondrial biogenesis and a role in maintaining mitochondrial ETC activity. Dysfunction of both has been implicated in sporadic forms of PD suggesting that these may be key pathways in the development of the disease.

  11. Evolutional dynamics of 45S and 5S ribosomal DNA in ancient allohexaploid Atropa belladonna.

    Science.gov (United States)

    Volkov, Roman A; Panchuk, Irina I; Borisjuk, Nikolai V; Hosiawa-Baranska, Marta; Maluszynska, Jolanta; Hemleben, Vera

    2017-01-23

    inheritance from the tetraploid progenitor. The obtained molecular, cytogenetic and phylogenetic data demonstrate complex evolutionary dynamics of rDNA loci in allohexaploid species of Atropa belladonna. The high level of sequence unification revealed in 45S and 5S rDNA loci of this ancient hybrid species have been seemingly achieved by different molecular mechanisms.

  12. Phylogenetic Reconstruction Shows Independent Evolutionary Origins of Mitochondrial Transcription Factors from an Ancient Family of RNA Methyltransferase Proteins.

    Science.gov (United States)

    Aj Harris; Goldman, Aaron David

    2018-04-25

    Here, we generate a robust phylogenetic framework for the rRNA adenine N(6)-methyltransferase (RAMTase) protein family that shows a more ancient and complex evolutionary history within the family than previously reported. RAMTases occur universally by descent across the three domains of life, and typical orthologs within the family perform methylation of the small subunits of ribosomal RNA (rRNA). However, within the RAMTase family, two different groups of mitochondrial transcription factors, mtTFB1 and mtTFB2, have evolved in eukaryotes through neofunctionalization. Previous phylogenetic analyses have suggested that mtTFB1 and mtTFB2 comprise sister clades that arose via gene duplication, which occurred sometime following the endosymbiosis event that produced the mitochondrion. Through dense and taxonomically broad sampling of RAMTase family members especially within bacteria, we found that these eukaryotic mitochondrial transcription factors, mtTFB1 and mtTFB2, have independent origins in phylogenetically distant clades such that their divergence most likely predates the last universal common ancestor of life. The clade of mtTFB2s comprises orthologs in Opisthokonts and the clade of mtTFB1s includes orthologs in Amoebozoa and Metazoa. Thus, we clearly demonstrate that the neofunctionalization producing the transcription factor function evolved twice independently within the RAMTase family. These results are consistent with and help to elucidate outcomes from prior experimental studies, which found that some members of mtTFB1 still perform the ancestral rRNA methylation function, and the results have broader implications for understanding the evolution of new protein functions. Our phylogenetic reconstruction is also in agreement with prior studies showing two independent origins of plastid RAMTases in Viridiplantae and other photosynthetic autotrophs. We believe that this updated phylogeny of RAMTases should provide a robust evolutionary framework for ongoing

  13. Mitochondrial and Nuclear DNA Damage and Repair in Age-Related Macular Degeneration

    Directory of Open Access Journals (Sweden)

    Janusz Blasiak

    2013-01-01

    Full Text Available Aging and oxidative stress seem to be the most important factors in the pathogenesis of age-related macular degeneration (AMD, a condition affecting many elderly people in the developed world. However, aging is associated with the accumulation of oxidative damage in many biomolecules, including DNA. Furthermore, mitochondria may be especially important in this process because the reactive oxygen species produced in their electron transport chain can damage cellular components. Therefore, the cellular response to DNA damage, expressed mainly through DNA repair, may play an important role in AMD etiology. In several studies the increase in mitochondrial DNA (mtDNA damage and mutations, and the decrease in the efficacy of DNA repair have been correlated with the occurrence and the stage of AMD. It has also been shown that mitochondrial DNA accumulates more DNA lesions than nuclear DNA in AMD. However, the DNA damage response in mitochondria is executed by nucleus-encoded proteins, and thus mutagenesis in nuclear DNA (nDNA may affect the ability to respond to mutagenesis in its mitochondrial counterpart. We reported that lymphocytes from AMD patients displayed a higher amount of total endogenous basal and oxidative DNA damage, exhibited a higher sensitivity to hydrogen peroxide and UV radiation, and repaired the lesions induced by these factors less effectively than did cells from control individuals. We postulate that poor efficacy of DNA repair (i.e., is impaired above average for a particular age when combined with the enhanced sensitivity of retinal pigment epithelium cells to environmental stress factors, contributes to the pathogenesis of AMD. Collectively, these data suggest that the cellular response to both mitochondrial and nuclear DNA damage may play an important role in AMD pathogenesis.

  14. Age-related mitochondrial DNA depletion and the impact on pancreatic Beta cell function.

    Science.gov (United States)

    Nile, Donna L; Brown, Audrey E; Kumaheri, Meutia A; Blair, Helen R; Heggie, Alison; Miwa, Satomi; Cree, Lynsey M; Payne, Brendan; Chinnery, Patrick F; Brown, Louise; Gunn, David A; Walker, Mark

    2014-01-01

    Type 2 diabetes is characterised by an age-related decline in insulin secretion. We previously identified a 50% age-related decline in mitochondrial DNA (mtDNA) copy number in isolated human islets. The purpose of this study was to mimic this degree of mtDNA depletion in MIN6 cells to determine whether there is a direct impact on insulin secretion. Transcriptional silencing of mitochondrial transcription factor A, TFAM, decreased mtDNA levels by 40% in MIN6 cells. This level of mtDNA depletion significantly decreased mtDNA gene transcription and translation, resulting in reduced mitochondrial respiratory capacity and ATP production. Glucose-stimulated insulin secretion was impaired following partial mtDNA depletion, but was normalised following treatment with glibenclamide. This confirms that the deficit in the insulin secretory pathway precedes K+ channel closure, indicating that the impact of mtDNA depletion is at the level of mitochondrial respiration. In conclusion, partial mtDNA depletion to a degree comparable to that seen in aged human islets impaired mitochondrial function and directly decreased insulin secretion. Using our model of partial mtDNA depletion following targeted gene silencing of TFAM, we have managed to mimic the degree of mtDNA depletion observed in aged human islets, and have shown how this correlates with impaired insulin secretion. We therefore predict that the age-related mtDNA depletion in human islets is not simply a biomarker of the aging process, but will contribute to the age-related risk of type 2 diabetes.

  15. Phylogeography of the asian elephant (Elephas maximus) based on mitochondrial DNA.

    Science.gov (United States)

    Fleischer, R C; Perry, E A; Muralidharan, K; Stevens, E E; Wemmer, C M

    2001-09-01

    Populations of the Asian elephant (Elephas maximus) have been reduced in size and become highly fragmented during the past 3,000 to 4,000 years. Historical records reveal elephant dispersal by humans via trade and war. How have these anthropogenic impacts affected genetic variation and structure of Asian elephant populations? We sequenced mitochondrial DNA (mtDNA) to assay genetic variation and phylogeography across much of the Asian elephant's range. Initially we compare cytochrome b sequences (cyt b) between nine Asian and five African elephants and use the fossil-based age of their separation (approximately 5 million years ago) to obtain a rate of about 0.013 (95% CI = 0.011-0.018) corrected sequence divergence per million years. We also assess variation in part of the mtDNA control region (CR) and adjacent tRNA genes in 57 Asian elephants from seven countries (Sri Lanka, India, Nepal, Myanmar, Thailand, Malaysia, and Indonesia). Asian elephants have typical levels of mtDNA variation, and coalescence analyses suggest their populations were growing in the late Pleistocene. Reconstructed phylogenies reveal two major clades (A and B) differing on average by HKY85/gamma-corrected distances of 0.020 for cyt b and 0.050 for the CR segment (corresponding to a coalescence time based on our cyt b rate of approximately 1.2 million years). Individuals of both major clades exist in all locations but Indonesia and Malaysia. Most elephants from Malaysia and all from Indonesia are in well-supported, basal clades within clade A. thus supporting their status as evolutionarily significant units (ESUs). The proportion of clade A individuals decreases to the north, which could result from retention and subsequent loss of ancient lineages in long-term stable populations or, perhaps more likely, via recent mixing of two expanding populations that were isolated in the mid-Pleistocene. The distribution of clade A individuals appears to have been impacted by human trade in elephants

  16. Recent volcanism and mitochondrial DNA structuring in the lizard Gallotia atlantica from the island of Lanzarote.

    Science.gov (United States)

    Bloor, P; Kemp, S J; Brown, R P

    2008-02-01

    The phylogeography of the lacertid lizard Gallotia atlantica from the small volcanic island of Lanzarote (Canary Islands) was analysed based on 1075 bp of mitochondrial DNA (mtDNA) sequence (partial cytochrome b and ND2) for 157 individuals from 27 sites (including three sites from neighbouring islets). Levels of sequence divergence were generally low, with the most distant haplotypes separated by only 14 mutational steps. MtDNA divergence appears to coincide with formation of the middle Pleistocene lowland that united formerly separate ancient islands to form the current island of Lanzarote, allowing rejection of a two-island model of phylogeographical structure. There was evidence of large-scale population expansion after island unification, consistent with the colonization of new areas. A nested clade phylogeographical analysis (NCPA) revealed significant phylogeographical structuring. Two-step and higher-level clades each had disjunct distributions, being found to the east and west of a common area with a north-south orientation that extends between coasts in the centre-east of the island (El Jable). Other clades were almost entirely restricted to the El Jable region alone. Bayesian Markov chain Monte Carlo analyses were used to separate ongoing gene flow from historical associations. These supported the NCPA by indicating recent (75,000-150,000 years ago) east-west vicariance across the El Jable region. Lava flows covered El Jable and other parts of the central lowland at this time and likely led to population extinctions and temporary dispersal barriers, although present-day evidence suggests some populations would have survived in small refugia. Expansion of the latter appears to explain the presence of a clade located between the eastern and western components of the disjunct clades. Direct relationships between mtDNA lineages and morphology were not found, although one of two morphological forms on the island has a disjunct distribution that is broadly

  17. Detection of irradiated fresh, chilled, and frozen foods by the mitochondrial DNA method

    International Nuclear Information System (INIS)

    Machioni, E.; Bergaentzle, M.; Todoriki, S.; Hasselmann, C.; Kuntz, F.

    1996-01-01

    DNA molecules are very sensitive to ionising radiation, even at low doses. Strand breaks are easy to detect despite the generally low DNA content of foods, but such ruptures are not specific to radiation processing. Preliminary experiments showed that cellular DNA in beef underwent strong enzymatic degradation during storage at +4 o C and thus radiation effects could not be isolated. In order to make DNA strand rupture more specific to radiation (other than by deep freezing) it appears necessary to isolate the irradiated DNA from cell enzymes. This is the case for mitochondrial DNA which is protected from enzymatic degradation by the mitochondrial walls but not from radiation. It can, therefore, be assumed that DNA strand breaks in mitochondria will be specific to ionising radiation. The aim of this work is to develop and validate the proposed test on different food samples (meat and fish products) which are already or may be industrially irradiated in the near future. (author)

  18. DNA typing of ancient parasite eggs from environmental samples identifies human and animal worm infections in viking-age settlement

    DEFF Research Database (Denmark)

    Søe, Martin Jensen; Nejsum, Peter; Fredensborg, Brian Lund

    2015-01-01

    Ancient parasite eggs were recovered from environmental samples collected at a Viking-age settlement in Viborg, Denmark, dated 1018-1030 A.D. Morphological examination identified Ascaris sp., Trichuris sp., and Fasciola sp. eggs, but size and shape did not allow species identification. By carefully...... selecting genetic markers, PCR amplification and sequencing of ancient DNA (aDNA) isolates resulted in identification of: the human whipworm, Trichuris trichiura, using SSUrRNA sequence homology; Ascaris sp. with 100% homology to cox1 haplotype 07; and Fasciola hepatica using ITS1 sequence homology...

  19. Mitochondrial DNA copy number in peripheral blood cells declines with age and is associated with general health among elderly

    DEFF Research Database (Denmark)

    Mengel-From, Jonas; Thinggaard, Mikael; Dalgård, Christine

    2014-01-01

    compared to nuclear DNA, i.e. the mitochondrial DNA copy number, was measured by PCR technology and used as a proxy for the content of mitochondria copies. In 1,067 Danish twins and singletons (18-93 years of age), with the majority being elderly individuals, the estimated mean mitochondrial DNA copy...

  20. Ancient microbes from halite fluid inclusions: optimized surface sterilization and DNA extraction.

    Directory of Open Access Journals (Sweden)

    Krithivasan Sankaranarayanan

    Full Text Available Fluid inclusions in evaporite minerals (halite, gypsum, etc. potentially preserve genetic records of microbial diversity and changing environmental conditions of Earth's hydrosphere for nearly one billion years. Here we describe a robust protocol for surface sterilization and retrieval of DNA from fluid inclusions in halite that, unlike previously published methods, guarantees removal of potentially contaminating surface-bound DNA. The protocol involves microscopic visualization of cell structures, deliberate surface contamination followed by surface sterilization with acid and bleach washes, and DNA extraction using Amicon centrifugal filters. Methods were verified on halite crystals of four different ages from Saline Valley, California (modern, 36 ka, 64 ka, and 150 ka, with retrieval of algal and archaeal DNA, and characterization of the algal community using ITS1 sequences. The protocol we developed opens up new avenues for study of ancient microbial ecosystems in fluid inclusions, understanding microbial evolution across geological time, and investigating the antiquity of life on earth and other parts of the solar system.

  1. The effect of chronic alcohol consumption on mitochondrial DNA mutagenesis in human blood

    Energy Technology Data Exchange (ETDEWEB)

    Wurmb-Schwark, N. von [Institute of Legal Medicine, Christian Albrecht University of Kiel, Arnold-Heller-Str. 12, 24105 Kiel (Germany)], E-mail: nvonwurmb@rechtsmedizin.uni-kiel.de; Ringleb, A.; Schwark, T. [Institute of Legal Medicine, Christian Albrecht University of Kiel, Arnold-Heller-Str. 12, 24105 Kiel (Germany); Broese, T.; Weirich, S.; Schlaefke, D. [Clinic of Psychiatry and Psychotherapy, University of Rostock, Gehlsheimer Str. 20, Rostock (Germany); Wegener, R. [Institute of Legal Medicine, St-Georg-Str. 108, University of Rostock, 18055 Rostock (Germany); Oehmichen, M. [Institute of Legal Medicine, Christian Albrecht University of Kiel, Arnold-Heller-Str. 12, 24105 Kiel (Germany)

    2008-01-01

    The 4977 bp deletion of mitochondrial DNA (mtDNA) is known to accumulate with increasing age in post mitotic tissues. Recently, studies came out detecting this specific alteration also in fast replicating cells, e.g. in blood or skin tissue, often in correlation to specific diseases or - specifically in skin - external stressors such as UV radiation. In this study, we investigated mitochondrial mutagenesis in 69 patients with a chronic alcoholic disease and 46 age matched controls with a moderate drinking behavior. Two different fragments, specific for total and for deleted mtDNA (dmtDNA) were amplified in a duplex-PCR. A subsequent fragment analysis was performed and for relative quantification, the quotient of the peak areas of amplification products specific for deleted and total mtDNA was determined. Additionally, a real time PCR was performed to quantify mtDNA copy number. The relative amount of 4977 bp deleted mtDNA in alcoholics was significantly increased compared to controls. On the other hand, no difference regarding the mtDNA/nuclear DNA ratio in both investigated groups was detected. Additionally, no age dependence could be found nor in alcoholics, neither in the control group. These findings indicate that mtDNA mutagenesis in blood can be influenced by stressors such as alcohol. Ethanol seems to be a significant factor to alter mitochondrial DNA in blood and might be an additional contributor for the cellular aging process.

  2. The effect of chronic alcohol consumption on mitochondrial DNA mutagenesis in human blood

    International Nuclear Information System (INIS)

    Wurmb-Schwark, N. von; Ringleb, A.; Schwark, T.; Broese, T.; Weirich, S.; Schlaefke, D.; Wegener, R.; Oehmichen, M.

    2008-01-01

    The 4977 bp deletion of mitochondrial DNA (mtDNA) is known to accumulate with increasing age in post mitotic tissues. Recently, studies came out detecting this specific alteration also in fast replicating cells, e.g. in blood or skin tissue, often in correlation to specific diseases or - specifically in skin - external stressors such as UV radiation. In this study, we investigated mitochondrial mutagenesis in 69 patients with a chronic alcoholic disease and 46 age matched controls with a moderate drinking behavior. Two different fragments, specific for total and for deleted mtDNA (dmtDNA) were amplified in a duplex-PCR. A subsequent fragment analysis was performed and for relative quantification, the quotient of the peak areas of amplification products specific for deleted and total mtDNA was determined. Additionally, a real time PCR was performed to quantify mtDNA copy number. The relative amount of 4977 bp deleted mtDNA in alcoholics was significantly increased compared to controls. On the other hand, no difference regarding the mtDNA/nuclear DNA ratio in both investigated groups was detected. Additionally, no age dependence could be found nor in alcoholics, neither in the control group. These findings indicate that mtDNA mutagenesis in blood can be influenced by stressors such as alcohol. Ethanol seems to be a significant factor to alter mitochondrial DNA in blood and might be an additional contributor for the cellular aging process

  3. Ancient genomes

    OpenAIRE

    Hoelzel, A Rus

    2005-01-01

    Ever since its invention, the polymerase chain reaction has been the method of choice for work with ancient DNA. In an application of modern genomic methods to material from the Pleistocene, a recent study has instead undertaken to clone and sequence a portion of the ancient genome of the cave bear.

  4. Mitochondrial DNA analysis of medieval sheep (Ovis aries) in central Italy reveals the predominance of haplogroup B already in the Middle Ages.

    Science.gov (United States)

    Gabbianelli, F; Gargani, M; Pariset, L; Mariotti, M; Alhaique, F; De Minicis, E; Barelli, L; Ciammetti, E; Redi, F; Valentini, A

    2015-06-01

    We retrieved 34 medieval ovicaprine remains, from three archaeological sites of central Italy dating to about 1000 years old, and analyzed them using mitochondrial DNA. We compared the reconstructed haplogroups with modern sheep samples from Europe and the Middle East and sequences from the literature. In modern sheep, haplogroup HA is present in countries with access to the Mediterranean and close to the domestication center, whereas it is very rare or absent in the rest of Europe. The haplogroup HB was predominant in ancient samples (90%), whereas haplogroup HA was found at 10%. Ancient haplogroups match the present distribution in modern sheep in Italy, indicating that the current proportion of HA/HB was already established in the Middle Ages and is not the result of subsequent events such as selective breeding practices. © 2015 Stichting International Foundation for Animal Genetics.

  5. Assessment of precision and concordance of quantitative mitochondrial DNA assays: a collaborative international quality assurance study

    NARCIS (Netherlands)

    Hammond, Emma L.; Sayer, David; Nolan, David; Walker, Ulrich A.; Ronde, Anthony de; Montaner, Julio S. G.; Cote, Helene C. F.; Gahan, Michelle E.; Cherry, Catherine L.; Wesselingh, Steven L.; Reiss, Peter; Mallal, Simon

    2003-01-01

    Background: A number of international research groups have developed DNA quantitation assays in order to investigate the role of mitochondrial DNA depletion in anti-retroviral therapy-induced toxicities. Objectives: A collaborative study was undertaken to evaluate intra-assay precision and between

  6. In vitro-reconstituted nucleoids can block mitochondrial DNA replication and transcription

    NARCIS (Netherlands)

    Farge, Géraldine; Mehmedovic, Majda; Baclayon, Marian; van den Wildenberg, Siet M J L; Roos, Wouter H; Gustafsson, Claes M; Wuite, Gijs J L; Falkenberg, Maria

    2014-01-01

    The mechanisms regulating the number of active copies of mtDNA are still unclear. A mammalian cell typically contains 1,000-10,000 copies of mtDNA, which are packaged into nucleoprotein complexes termed nucleoids. The main protein component of these structures is mitochondrial transcription factor A

  7. Introducing Human Population Biology through an Easy Laboratory Exercise on Mitochondrial DNA

    Science.gov (United States)

    Pardinas, Antonio F.; Dopico, Eduardo; Roca, Agustin; Garcia-Vazquez, Eva; Lopez, Belen

    2010-01-01

    This article describes an easy and cheap laboratory exercise for students to discover their own mitochondrial haplogroup. Students use buccal swabs to obtain mucosa cells as noninvasive tissue samples, extract DNA, and with a simple polymerase chain reaction-restriction fragment length polymorphism analysis they can obtain DNA fragments of…

  8. Replication of vertebrate mitochondrial DNA entails transient ribonucleotide incorporation throughout the lagging strand.

    Science.gov (United States)

    Yasukawa, Takehiro; Reyes, Aurelio; Cluett, Tricia J; Yang, Ming-Yao; Bowmaker, Mark; Jacobs, Howard T; Holt, Ian J

    2006-11-15

    Using two-dimensional agarose gel electrophoresis, we show that mitochondrial DNA (mtDNA) replication of birds and mammals frequently entails ribonucleotide incorporation throughout the lagging strand (RITOLS). Based on a combination of two-dimensional agarose gel electrophoretic analysis and mapping of 5' ends of DNA, initiation of RITOLS replication occurs in the major non-coding region of vertebrate mtDNA and is effectively unidirectional. In some cases, conversion of nascent RNA strands to DNA starts at defined loci, the most prominent of which maps, in mammalian mtDNA, in the vicinity of the site known as the light-strand origin.

  9. The mitochondrial and plastid genomes of Volvox carteri: bloated molecules rich in repetitive DNA

    Directory of Open Access Journals (Sweden)

    Lee Robert W

    2009-03-01

    Full Text Available Abstract Background The magnitude of noncoding DNA in organelle genomes can vary significantly; it is argued that much of this variation is attributable to the dissemination of selfish DNA. The results of a previous study indicate that the mitochondrial DNA (mtDNA of the green alga Volvox carteri abounds with palindromic repeats, which appear to be selfish elements. We became interested in the evolution and distribution of these repeats when, during a cursory exploration of the V. carteri nuclear DNA (nucDNA and plastid DNA (ptDNA sequences, we found palindromic repeats with similar structural features to those of the mtDNA. Upon this discovery, we decided to investigate the diversity and evolutionary implications of these palindromic elements by sequencing and characterizing large portions of mtDNA and ptDNA and then comparing these data to the V. carteri draft nuclear genome sequence. Results We sequenced 30 and 420 kilobases (kb of the mitochondrial and plastid genomes of V. carteri, respectively – resulting in partial assemblies of these genomes. The mitochondrial genome is the most bloated green-algal mtDNA observed to date: ~61% of the sequence is noncoding, most of which is comprised of short palindromic repeats spread throughout the intergenic and intronic regions. The plastid genome is the largest (>420 kb and most expanded (>80% noncoding ptDNA sequence yet discovered, with a myriad of palindromic repeats in the noncoding regions, which have a similar size and secondary structure to those of the mtDNA. We found that 15 kb (~0.01% of the nuclear genome are homologous to the palindromic elements of the mtDNA, and 50 kb (~0.05% are homologous to those of the ptDNA. Conclusion Selfish elements in the form of short palindromic repeats have propagated in the V. carteri mtDNA and ptDNA, resulting in the distension of these genomes. Copies of these same repeats are also found in a small fraction of the nucDNA, but appear to be inert in this

  10. Genetic characteristics of mitochondrial DNA was associated with colorectal carcinogenesis and its prognosis.

    Directory of Open Access Journals (Sweden)

    Jae-Ho Lee

    Full Text Available Clinical value of mitochondrial DNA has been described in colorectal cancer (CRC. To clarify its role in colorectal carcinogenesis, mitochondrial microsatellite instability (mtMSI and other markers were investigated in CRCs and their precancerous lesions, as a multitier genetic study. DNA was isolated from paired normal and tumoral tissues in 78 tubular adenomas (TAs, 34 serrated polyps (SPs, and 100 CRCs. mtMSI, nucleus microsatellite instability (nMSI, KRAS mutation, and BRAF mutation were investigated in these tumors and their statistical analysis was performed. mtMSI was found in 30% of CRCs and 21.4% of precancerous lesions. Mitochondrial copy number was higher in SPs than TAs and it was associated with mtMSI in low grade TAs. KRAS and BRAF mutations were mutually exclusive in TAs and SPs. CRCs with mtMSI showed shorter overall survival times than the patients without mtMSI. In CRCs without nMSI or BRAF mutation, mtMSI was a more accurate marker for predicting prognosis. The genetic change of mitochondrial DNA is an early and independent event in colorectal precancerous lesions and mtMSI and mitochondrial contents are associated with the tubular adenoma-carcinoma sequence, resulting in poor prognosis. This result suggested that the genetic change in mitochondrial DNA appears to be a possible prognosis marker in CRC.

  11. Molecular dating of caprines using ancient DNA sequences of Myotragus balearicus, an extinct endemic Balearic mammal

    Directory of Open Access Journals (Sweden)

    Alcover Josep Antoni

    2005-12-01

    Full Text Available Abstract Background Myotragus balearicus was an endemic bovid from the Balearic Islands (Western Mediterranean that became extinct around 6,000-4,000 years ago. The Myotragus evolutionary lineage became isolated in the islands most probably at the end of the Messinian crisis, when the desiccation of the Mediterranean ended, in a geological date established at 5.35 Mya. Thus, the sequences of Myotragus could be very valuable for calibrating the mammalian mitochondrial DNA clock and, in particular, the tree of the Caprinae subfamily, to which Myotragus belongs. Results We have retrieved the complete mitochondrial cytochrome b gene (1,143 base pairs, plus fragments of the mitochondrial 12S gene and the nuclear 28S rDNA multi-copy gene from a well preserved Myotragus subfossil bone. The best resolved phylogenetic trees, obtained with the cytochrome b gene, placed Myotragus in a position basal to the Ovis group. Using the calibration provided by the isolation of Balearic Islands, we calculated that the initial radiation of caprines can be dated at 6.2 ± 0.4 Mya. In addition, alpine and southern chamois, considered until recently the same species, split around 1.6 ± 0.3 Mya, indicating that the two chamois species have been separated much longer than previously thought. Conclusion Since there are almost no extant endemic mammals in Mediterranean islands, the sequence of the extinct Balearic endemic Myotragus has been crucial for allowing us to use the Messinian crisis calibration point for dating the caprines phylogenetic tree.

  12. Multi-scale ancient DNA analyses confirm the western origin of Michelsberg farmers and document probable practices of human sacrifice.

    Directory of Open Access Journals (Sweden)

    Alice Beau

    Full Text Available In Europe, the Middle Neolithic is characterized by an important diversification of cultures. In northeastern France, the appearance of the Michelsberg culture has been correlated with major cultural changes and interpreted as the result of the settlement of new groups originating from the Paris Basin. This cultural transition has been accompanied by the expansion of particular funerary practices involving inhumations within circular pits and individuals in "non-conventional" positions (deposited in the pits without any particular treatment. If the status of such individuals has been highly debated, the sacrifice hypothesis has been retained for the site of Gougenheim (Alsace. At the regional level, the analysis of the Gougenheim mitochondrial gene pool (SNPs and HVR-I sequence analyses permitted us to highlight a major genetic break associated with the emergence of the Michelsberg in the region. This genetic discontinuity appeared to be linked to new affinities with farmers from the Paris Basin, correlated to a noticeable hunter-gatherer legacy. All of the evidence gathered supports (i the occidental origin of the Michelsberg groups and (ii the potential implication of this migration in the progression of the hunter-gatherer legacy from the Paris Basin to Alsace / Western Germany at the beginning of the Late Neolithic. At the local level, we noted some differences in the maternal gene pool of individuals in "conventional" vs. "non-conventional" positions. The relative genetic isolation of these sub-groups nicely echoes both their social distinction and the hypothesis of sacrifices retained for the site. Our investigation demonstrates that a multi-scale aDNA study of ancient communities offers a unique opportunity to disentangle the complex relationships between cultural and biological evolution.

  13. Archaeal community changes in Lateglacial lake sediments: Evidence from ancient DNA

    Science.gov (United States)

    Ahmed, Engy; Parducci, Laura; Unneberg, Per; Ågren, Rasmus; Schenk, Frederik; Rattray, Jayne E.; Han, Lu; Muschitiello, Francesco; Pedersen, Mikkel W.; Smittenberg, Rienk H.; Yamoah, Kweku Afrifa; Slotte, Tanja; Wohlfarth, Barbara

    2018-02-01

    The Lateglacial/early Holocene sediments from the ancient lake at Hässeldala Port, southern Sweden provide an important archive for the environmental and climatic shifts at the end of the last ice age and the transition into the present Interglacial. The existing multi-proxy data set highlights the complex interplay of physical and ecological changes in response to climatic shifts and lake status changes. Yet, it remains unclear how microorganisms, such as Archaea, which do not leave microscopic features in the sedimentary record, were affected by these climatic shifts. Here we present the metagenomic data set of Hässeldala Port with a special focus on the abundance and biodiversity of Archaea. This allows reconstructing for the first time the temporal succession of major Archaea groups between 13.9 and 10.8 ka BP by using ancient environmental DNA metagenomics and fossil archaeal cell membrane lipids. We then evaluate to which extent these findings reflect physical changes of the lake system, due to changes in lake-water summer temperature and seasonal lake-ice cover. We show that variations in archaeal composition and diversity were related to a variety of factors (e.g., changes in lake water temperature, duration of lake ice cover, rapid sediment infilling), which influenced bottom water conditions and the sediment-water interface. Methanogenic Archaea dominated during the Allerød and Younger Dryas pollen zones, when the ancient lake was likely stratified and anoxic for large parts of the year. The increase in archaeal diversity at the Younger Dryas/Holocene transition is explained by sediment infilling and formation of a mire/peatbog.

  14. Mitochondrial DNA is a direct target of anti-cancer anthracycline drugs

    International Nuclear Information System (INIS)

    Ashley, Neil; Poulton, Joanna

    2009-01-01

    The anthracyclines, such as doxorubicin (DXR), are potent anti-cancer drugs but they are limited by their clinical toxicity. The mechanisms involved remain poorly understood partly because of the difficulty in determining sub-cellular drug localisation. Using a novel method utilising the fluorescent DNA dye PicoGreen, we found that anthracyclines intercalated not only into nuclear DNA but also mitochondrial DNA (mtDNA). Intercalation of mtDNA by anthracyclines may thus contribute to the marked mitochondrial toxicity associated with these drugs. By contrast, ethidium bromide intercalated exclusively into mtDNA, without interacting with nuclear DNA, thereby explaining why mtDNA is the main target for ethidium. By exploiting PicoGreen quenching we also developed a novel assay for quantification of mtDNA levels by flow-cytometry, an approach which should be useful for studies of mitochondrial dysfunction. In summary our PicoGreen assay should be useful to study drug/DNA interactions within live cells, and facilitate therapeutic drug monitoring and kinetic studies in cancer patients.

  15. Nucleotide pools dictate the identity and frequency of ribonucleotide incorporation in mitochondrial DNA.

    Directory of Open Access Journals (Sweden)

    Anna-Karin Berglund

    2017-02-01

    Full Text Available Previous work has demonstrated the presence of ribonucleotides in human mitochondrial DNA (mtDNA and in the present study we use a genome-wide approach to precisely map the location of these. We find that ribonucleotides are distributed evenly between the heavy- and light-strand of mtDNA. The relative levels of incorporated ribonucleotides reflect that DNA polymerase γ discriminates the four ribonucleotides differentially during DNA synthesis. The observed pattern is also dependent on the mitochondrial deoxyribonucleotide (dNTP pools and disease-causing mutations that change these pools alter both the absolute and relative levels of incorporated ribonucleotides. Our analyses strongly suggest that DNA polymerase γ-dependent incorporation is the main source of ribonucleotides in mtDNA and argues against the existence of a mitochondrial ribonucleotide excision repair pathway in human cells. Furthermore, we clearly demonstrate that when dNTP pools are limiting, ribonucleotides serve as a source of building blocks to maintain DNA replication. Increased levels of embedded ribonucleotides in patient cells with disturbed nucleotide pools may contribute to a pathogenic mechanism that affects mtDNA stability and impair new rounds of mtDNA replication.

  16. Nucleotide pools dictate the identity and frequency of ribonucleotide incorporation in mitochondrial DNA.

    Science.gov (United States)

    Berglund, Anna-Karin; Navarrete, Clara; Engqvist, Martin K M; Hoberg, Emily; Szilagyi, Zsolt; Taylor, Robert W; Gustafsson, Claes M; Falkenberg, Maria; Clausen, Anders R

    2017-02-01

    Previous work has demonstrated the presence of ribonucleotides in human mitochondrial DNA (mtDNA) and in the present study we use a genome-wide approach to precisely map the location of these. We find that ribonucleotides are distributed evenly between the heavy- and light-strand of mtDNA. The relative levels of incorporated ribonucleotides reflect that DNA polymerase γ discriminates the four ribonucleotides differentially during DNA synthesis. The observed pattern is also dependent on the mitochondrial deoxyribonucleotide (dNTP) pools and disease-causing mutations that change these pools alter both the absolute and relative levels of incorporated ribonucleotides. Our analyses strongly suggest that DNA polymerase γ-dependent incorporation is the main source of ribonucleotides in mtDNA and argues against the existence of a mitochondrial ribonucleotide excision repair pathway in human cells. Furthermore, we clearly demonstrate that when dNTP pools are limiting, ribonucleotides serve as a source of building blocks to maintain DNA replication. Increased levels of embedded ribonucleotides in patient cells with disturbed nucleotide pools may contribute to a pathogenic mechanism that affects mtDNA stability and impair new rounds of mtDNA replication.

  17. Mitochondrial DNA depletion syndrome presenting with ataxia and ...

    African Journals Online (AJOL)

    Laila Selim

    2012-07-24

    Jul 24, 2012 ... Sequencing analysis of the TK2 gene revealed no sequence variation. ... the pathogenesis of the myopathic form of mitochondrial depletion syndrome should be ..... [39,40]. However, the biochemical evidence of deficiency of.

  18. Ancient DNA reveals the Arctic origin of Viking Age cod from Haithabu, Germany.

    Science.gov (United States)

    Star, Bastiaan; Boessenkool, Sanne; Gondek, Agata T; Nikulina, Elena A; Hufthammer, Anne Karin; Pampoulie, Christophe; Knutsen, Halvor; André, Carl; Nistelberger, Heidi M; Dierking, Jan; Petereit, Christoph; Heinrich, Dirk; Jakobsen, Kjetill S; Stenseth, Nils Chr; Jentoft, Sissel; Barrett, James H

    2017-08-22

    Knowledge of the range and chronology of historic trade and long-distance transport of natural resources is essential for determining the impacts of past human activities on marine environments. However, the specific biological sources of imported fauna are often difficult to identify, in particular if species have a wide spatial distribution and lack clear osteological or isotopic differentiation between populations. Here, we report that ancient fish-bone remains, despite being porous, brittle, and light, provide an excellent source of endogenous DNA (15-46%) of sufficient quality for whole-genome reconstruction. By comparing ancient sequence data to that of modern specimens, we determine the biological origin of 15 Viking Age (800-1066 CE) and subsequent medieval (1066-1280 CE) Atlantic cod ( Gadus morhua ) specimens from excavation sites in Germany, Norway, and the United Kingdom. Archaeological context indicates that one of these sites was a fishing settlement for the procurement of local catches, whereas the other localities were centers of trade. Fish from the trade sites show a mixed ancestry and are statistically differentiated from local fish populations. Moreover, Viking Age samples from Haithabu, Germany, are traced back to the North East Arctic Atlantic cod population that has supported the Lofoten fisheries of Norway for centuries. Our results resolve a long-standing controversial hypothesis and indicate that the marine resources of the North Atlantic Ocean were used to sustain an international demand for protein as far back as the Viking Age.

  19. The potential role for use of mitochondrial DNA copy number as predictive biomarker in presbycusis

    Directory of Open Access Journals (Sweden)

    Falah M

    2016-10-01

    Full Text Available Masoumeh Falah,1,2 Massoud Houshmand,3 Mohammad Najafi,2 Maryam Balali,1 Saeid Mahmoudian,1 Alimohamad Asghari,4 Hessamaldin Emamdjomeh,1 Mohammad Farhadi1 1ENT and Head & Neck Research Center and Department, Iran University of Medical Sciences, Tehran, Iran; 2Cellular and Molecular Research Center, Biochemistry Department, Iran University of Medical Sciences, Tehran, Iran; 3Department of Medical Genetics, National Institute for Genetic Engineering and Biotechnology, Tehran, Iran; 4Skull base research center, Iran University of Medical Sciences, Tehran, Iran Objectives: Age-related hearing impairment, or presbycusis, is the most common communication disorder and neurodegenerative disease in the elderly. Its prevalence is expected to increase, due to the trend of growth of the elderly population. The current diagnostic test for detection of presbycusis is implemented after there has been a change in hearing sensitivity. Identification of a pre-diagnostic biomarker would raise the possibility of preserving hearing sensitivity before damage occurs. Mitochondrial dysfunction, including the production of reactive oxygen species and induction of expression of apoptotic genes, participates in the progression of presbycusis. Mitochondrial DNA sequence variation has a critical role in presbycusis. However, the nature of the relationship between mitochondrial DNA copy number, an important biomarker in many other diseases, and presbycusis is undetermined.Methods: Fifty-four subjects with presbycusis and 29 healthy controls were selected after ear, nose, throat examination and pure-tone audiometry. DNA was extracted from peripheral blood samples. The copy number of mitochondrial DNA relative to the nuclear genome was measured by quantitative real-time polymerase chain reaction.Results: Subjects with presbycusis had a lower median mitochondrial DNA copy number than healthy subjects and the difference was statistically significant (P=0.007. Mitochondrial DNA

  20. Multiplexed SNP Typing of Ancient DNA Clarifies the Origin of Andaman mtDNA Haplogroups amongst South Asian Tribal Populations

    Science.gov (United States)

    Endicott, Phillip; Metspalu, Mait; Stringer, Chris; Macaulay, Vincent; Cooper, Alan; Sanchez, Juan J.

    2006-01-01

    The issue of errors in genetic data sets is of growing concern, particularly in population genetics where whole genome mtDNA sequence data is coming under increased scrutiny. Multiplexed PCR reactions, combined with SNP typing, are currently under-exploited in this context, but have the potential to genotype whole populations rapidly and accurately, significantly reducing the amount of errors appearing in published data sets. To show the sensitivity of this technique for screening mtDNA genomic sequence data, 20 historic samples of the enigmatic Andaman Islanders and 12 modern samples from three Indian tribal populations (Chenchu, Lambadi and Lodha) were genotyped for 20 coding region sites after provisional haplogroup assignment with control region sequences. The genotype data from the historic samples significantly revise the topologies for the Andaman M31 and M32 mtDNA lineages by rectifying conflicts in published data sets. The new Indian data extend the distribution of the M31a lineage to South Asia, challenging previous interpretations of mtDNA phylogeography. This genetic connection between the ancestors of the Andamanese and South Asian tribal groups ∼30 kya has important implications for the debate concerning migration routes and settlement patterns of humans leaving Africa during the late Pleistocene, and indicates the need for more detailed genotyping strategies. The methodology serves as a low-cost, high-throughput model for the production and authentication of data from modern or ancient DNA, and demonstrates the value of museum collections as important records of human genetic diversity. PMID:17218991

  1. mtDNA, Metastasis, and the Mitochondrial Unfolded Protein Response (UPRmt).

    Science.gov (United States)

    Kenny, Timothy C; Germain, Doris

    2017-01-01

    While several studies have confirmed a link between mitochondrial DNA (mtDNA) mutations and cancer cell metastasis, much debate remains regarding the nature of the alternations in mtDNA leading to this effect. Meanwhile, the mitochondrial unfolded protein response (UPR mt ) has gained much attention in recent years, with most studies of this pathway focusing on its role in aging. However, the UPR mt has also been studied in the context of cancer. More recent work suggests that rather than a single mutation or alternation, specific combinatorial mtDNA landscapes able to activate the UPR mt may be those that are selected by metastatic cells, while mtDNA landscapes unable to activate the UPR mt do not. This review aims at offering an overview of the confusing literature on mtDNA mutations and metastasis and the more recent work on the UPR mt in this setting.

  2. Periodic expression of nuclear and mitochondrial DNA replication genes during the trypanosomatid cell cycle.

    Science.gov (United States)

    Pasion, S G; Brown, G W; Brown, L M; Ray, D S

    1994-12-01

    In trypanosomatids, DNA replication in the nucleus and in the single mitochondrion (or kinetoplast) initiates nearly simultaneously, suggesting that the DNA synthesis (S) phases of the nucleus and the mitochondrion are coordinately regulated. To investigate the basis for the temporal link between nuclear and mitochondrial DNA synthesis phases the expression of the genes encoding DNA ligase I, the 51 and 28 kDa subunits of replication protein A, dihydrofolate reductase and the mitochondrial type II topoisomerase were analyzed during the cell cycle progression of synchronous cultures of Crithidia fasciculata. These DNA replication genes were all expressed periodically, with peak mRNA levels occurring just prior to or at the peak of DNA synthesis in the synchronized cultures. A plasmid clone (pdN-1) in which TOP2, the gene encoding the mitochondrial topoisomerase, was disrupted by the insertion of a NEO drug-resistance cassette was found to express both a truncated TOP2 mRNA and a truncated topoisomerase polypeptide. The truncated mRNA was also expressed periodically coordinate with the expression of the endogenous TOP2 mRNA indicating that cis elements necessary for periodic expression are contained within cloned sequences. The expression of both TOP2 and nuclear DNA replication genes at the G1/S boundary suggests that regulated expression of these genes may play a role in coordinating nuclear and mitochondrial S phases in trypanosomatids.

  3. Slow mitochondrial repair of 5'-AMP renders mtDNA susceptible to damage in APTX deficient cells

    DEFF Research Database (Denmark)

    Akbari, Mansour; Sykora, Peter; Bohr, Vilhelm A

    2015-01-01

    deficient cells. Moreover, the removal of 5'-AMP from DNA was significantly slower in the mitochondrial extracts from human cell lines and mouse tissues compared with their corresponding nuclear extracts. These results suggest that, contrary to nuclear DNA repair, mitochondrial DNA repair is not able...... elucidated. Here, we monitored the repair of 5'-AMP DNA damage in nuclear and mitochondrial extracts from human APTX(+/+) and APTX(-/-) cells. The efficiency of repair of 5'-AMP DNA was much lower in mitochondrial than in nuclear protein extracts, and resulted in persistent DNA repair intermediates in APTX......Aborted DNA ligation events in eukaryotic cells can generate 5'-adenylated (5'-AMP) DNA termini that can be removed from DNA by aprataxin (APTX). Mutations in APTX cause an inherited human disease syndrome characterized by early-onset progressive ataxia with ocular motor apraxia (AOA1). APTX...

  4. Mitochondrial DNA Unwinding Enzyme Required for Liver Regeneration | Center for Cancer Research

    Science.gov (United States)

    The liver has an exceptional capacity to proliferate. This ability allows the liver to regenerate its mass after partial surgical removal or injury and is the key to successful partial liver transplants. Liver cells, called hepatocytes, are packed with mitochondria, and regulating mitochondrial DNA (mtDNA) copy number is crucial to mitochondrial function, including energy production, during proliferation. Yves Pommier, M.D., Ph.D., of CCR’s Developmental Therapeutics Branch, and his colleagues recently showed that the vertebrate mitochondrial topoisomerase, Top1mt, was critical in maintaining mitochondrial function in the heart after doxorubicin-induced damage. The group wondered whether Top1mt might play a similar role in liver regeneration.

  5. Molecular diversification of Trichuris spp. from Sigmodontinae (Cricetidae) rodents from Argentina based on mitochondrial DNA sequences.

    Science.gov (United States)

    Callejón, Rocío; Robles, María Del Rosario; Panei, Carlos Javier; Cutillas, Cristina

    2016-08-01

    A molecular phylogenetic hypothesis is presented for the genus Trichuris based on sequence data from mitochondrial cytochrome c oxidase 1 (cox1) and cytochrome b (cob). The taxa consisted of nine populations of whipworm from five species of Sigmodontinae rodents from Argentina. Bayesian Inference, Maximum Parsimony, and Maximum Likelihood methods were used to infer phylogenies for each gene separately but also for the combined mitochondrial data and the combined mitochondrial and nuclear dataset. Phylogenetic results based on cox1 and cob mitochondrial DNA (mtDNA) revealed three clades strongly resolved corresponding to three different species (Trichuris navonae, Trichuris bainae, and Trichuris pardinasi) showing phylogeographic variation, but relationships among Trichuris species were poorly resolved. Phylogenetic reconstruction based on concatenated sequences had greater phylogenetic resolution for delimiting species and populations intra-specific of Trichuris than those based on partitioned genes. Thus, populations of T. bainae and T. pardinasi could be affected by geographical factors and co-divergence parasite-host.

  6. Temporal pattern of africanization in a feral honeybee population from Texas inferred from mitochondrial DNA

    OpenAIRE

    Pinto, M. Alice; Rubink, William L.; Coulson, Robert N.; Patton, John C.; Johnston, J. Spencer

    2004-01-01

    The invasion of Africanized honeybees (Apis mellifera L.) in the Americas provides a window of opportunity to study the dynamics of secondary contact of subspecies of bees that evolved in allopatry in ecologically distinctive habitats of the Old World. We report here the results of an 11-year mitochondrial DNA survey of a feral honeybee population from southern United States (Texas). The mitochondrial haplotype (mitotype) frequencies changed radically during the 11-year study peri...

  7. Ancient DNA Analysis Suggests Negligible Impact of the Wari Empire Expansion in Peru’s Central Coast during the Middle Horizon

    Science.gov (United States)

    Barreto Romero, María Inés; Flores Espinoza, Isabel; Cooper, Alan; Fehren-Schmitz, Lars

    2016-01-01

    The analysis of ancient human DNA from South America allows the exploration of pre-Columbian population history through time and to directly test hypotheses about cultural and demographic evolution. The Middle Horizon (650–1100 AD) represents a major transitional period in the Central Andes, which is associated with the development and expansion of ancient Andean empires such as Wari and Tiwanaku. These empires facilitated a series of interregional interactions and socio-political changes, which likely played an important role in shaping the region’s demographic and cultural profiles. We analyzed individuals from three successive pre-Columbian cultures present at the Huaca Pucllana archaeological site in Lima, Peru: Lima (Early Intermediate Period, 500–700 AD), Wari (Middle Horizon, 800–1000 AD) and Ychsma (Late Intermediate Period, 1000–1450 AD). We sequenced 34 complete mitochondrial genomes to investigate the potential genetic impact of the Wari Empire in the Central Coast of Peru. The results indicate that genetic diversity shifted only slightly through time, ruling out a complete population discontinuity or replacement driven by the Wari imperialist hegemony, at least in the region around present-day Lima. However, we caution that the very subtle genetic contribution of Wari imperialism at the particular Huaca Pucllana archaeological site might not be representative for the entire Wari territory in the Peruvian Central Coast. PMID:27248693

  8. Preventing the transmission of mitochondrial DNA disorders using prenatal or preimplantation genetic diagnosis.

    Science.gov (United States)

    Smeets, Hubert J M; Sallevelt, Suzanne C E H; Dreesen, Jos C F M; de Die-Smulders, Christine E M; de Coo, Irenaeus F M

    2015-09-01

    Mitochondrial disorders are among the most common inborn errors of metabolism; at least 15% are caused by mitochondrial DNA (mtDNA) mutations, which occur de novo or are maternally inherited. For familial heteroplasmic mtDNA mutations, the mitochondrial bottleneck defines the mtDNA mutation load in offspring, with an often high or unpredictable recurrence risk. Oocyte donation is a safe option to prevent the transmission of mtDNA disease, but the offspring resulting from oocyte donation are genetically related only to the father. Prenatal diagnosis (PND) is technically possible but usually not applicable because of limitations in predicting the phenotype. For de novo mtDNA point mutations, recurrence risks are low and PND can be offered to provide reassurance regarding fetal health. PND is also the best option for female carriers with low-level mutations demonstrating skewing to 0% or 100%. A fairly new option for preventing the transmission of mtDNA diseases is preimplantation genetic diagnosis (PGD), in which embryos with a mutant load below a mutation-specific or general expression threshold of 18% can be transferred. PGD is currently the best reproductive option for familial heteroplasmic mtDNA point mutations. Nuclear genome transfer and genome editing techniques are currently being investigated and might offer additional reproductive options for specific mtDNA disease cases. © 2015 New York Academy of Sciences.

  9. Genotype-Phenotype Correlation of Maternally Inherited Disorders due to Mutations in Mitochondrial DNA

    Directory of Open Access Journals (Sweden)

    Peterus Thajeb

    2006-09-01

    Full Text Available Mitochondrial disorders are heterogeneous systemic ailments that are most often caused by maternal inheritance of a variety of mutations of the mitochondrial (mt DNA. Paternal inheritance and somatic mutation are rare. The disorders are well recognized not only for the genotypic heterogeneity, but also the phenotypic variation among the affected members of a single family. The genotype-phenotype correlation of the diversity of the syndromic and non-syndromic features of mitochondrial disorders are discussed. Some aspects of the molecular mechanisms of this heterogeneity, and the histopathologic findings are highlighted.

  10. A ketogenic diet accelerates neurodegeneration in mice with induced mitochondrial DNA toxicity in the forebrain.

    Science.gov (United States)

    Lauritzen, Knut H; Hasan-Olive, Md Mahdi; Regnell, Christine E; Kleppa, Liv; Scheibye-Knudsen, Morten; Gjedde, Albert; Klungland, Arne; Bohr, Vilhelm A; Storm-Mathisen, Jon; Bergersen, Linda H

    2016-12-01

    Mitochondrial genome maintenance plays a central role in preserving brain health. We previously demonstrated accumulation of mitochondrial DNA damage and severe neurodegeneration in transgenic mice inducibly expressing a mutated mitochondrial DNA repair enzyme (mutUNG1) selectively in forebrain neurons. Here, we examine whether severe neurodegeneration in mutUNG1-expressing mice could be rescued by feeding the mice a ketogenic diet, which is known to have beneficial effects in several neurological disorders. The diet increased the levels of superoxide dismutase 2, and mitochondrial mass, enzymes, and regulators such as SIRT1 and FIS1, and appeared to downregulate N-methyl-D-aspartic acid (NMDA) receptor subunits NR2A/B and upregulate γ-aminobutyric acid A (GABA A ) receptor subunits α 1 . However, unexpectedly, the ketogenic diet aggravated neurodegeneration and mitochondrial deterioration. Electron microscopy showed structurally impaired mitochondria accumulating in neuronal perikarya. We propose that aggravation is caused by increased mitochondrial biogenesis of generally dysfunctional mitochondria. This study thereby questions the dogma that a ketogenic diet is unambiguously beneficial in mitochondrial disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Mitochondrial DNA D-loop sequence variation among 5 maternal lines of the Zemaitukai horse breed

    Directory of Open Access Journals (Sweden)

    E. Gus Cothran

    2005-12-01

    Full Text Available Genetic variation in Zemaitukai horses was investigated using mitochondrial DNA (mtDNA sequencing. The study was performed on 421 bp of the mitochondrial DNA control region, which is known to be more variable than other sections of the mitochondrial genome. Samples from each of the remaining maternal family lines of Zemaitukai horses and three random samples for other Lithuanian (Lithuanian Heavy Draught, Zemaitukai large type and ten European horse breeds were sequenced. Five distinct haplotypes were obtained for the five Zemaitukai maternal families supporting the pedigree data. The minimal difference between two different sequence haplotypes was 6 and the maximal 11 nucleotides in Zemaitukai horse breed. A total of 20 nucleotide differences compared to the reference sequence were found in Lithuanian horse breeds. Genetic cluster analysis did not shown any clear pattern of relationship among breeds of different type.

  12. Retrospective assessment of the most common mitochondrial DNA mutations in a large Hungarian cohort of suspect mitochondrial cases.

    Science.gov (United States)

    Remenyi, Viktoria; Inczedy-Farkas, Gabriella; Komlosi, Katalin; Horvath, Rita; Maasz, Anita; Janicsek, Ingrid; Pentelenyi, Klara; Gal, Aniko; Karcagi, Veronika; Melegh, Bela; Molnar, Maria Judit

    2015-08-01

    Prevalence estimations for mitochondrial disorders still vary widely and only few epidemiologic studies have been carried out so far. With the present work we aim to give a comprehensive overview about frequencies of the most common mitochondrial mutations in Hungarian patients. A total of 1328 patients were tested between 1999 and 2012. Among them, 882 were screened for the m.3243A > G, m.8344A > G, m.8993T > C/G mutations and deletions, 446 for LHON primary mutations. The mutation frequency in our cohort was 2.61% for the m.3243A > G, 1.47% for the m.8344A > G, 17.94% for Leber's Hereditary Optic Neuropathy (m.3460G > A, m.11778G > A, m.14484T > C) and 0.45% for the m.8993T > C/G substitutions. Single mtDNA deletions were detected in 14.97%, while multiple deletions in 6.01% of the cases. The mutation frequency in Hungarian patients suggestive of mitochondrial disease was similar to other Caucasian populations. Further retrospective studies of different populations are needed in order to accurately assess the importance of mitochondrial diseases and manage these patients.

  13. Maternal age effect and severe germ-line bottleneck in the inheritance of human mitochondrial DNA

    DEFF Research Database (Denmark)

    Rebolledo-Jaramillo, Boris; Su, Marcia Shu-Wei; Stoler, Nicholas

    2014-01-01

    The manifestation of mitochondrial DNA (mtDNA) diseases depends on the frequency of heteroplasmy (the presence of several alleles in an individual), yet its transmission across generations cannot be readily predicted owing to a lack of data on the size of the mtDNA bottleneck during oogenesis......, an order of magnitude higher than for nuclear DNA. Notably, we found a positive association between the number of heteroplasmies in a child and maternal age at fertilization, likely attributable to oocyte aging. This study also took advantage of droplet digital PCR (ddPCR) to validate heteroplasmies...... and confirm a de novo mutation. Our results can be used to predict the transmission of disease-causing mtDNA variants and illuminate evolutionary dynamics of the mitochondrial genome....

  14. The last Viking King: a royal maternity case solved by ancient DNA analysis.

    Science.gov (United States)

    Dissing, Jørgen; Binladen, Jonas; Hansen, Anders; Sejrsen, Birgitte; Willerslev, Eske; Lynnerup, Niels

    2007-02-14

    The last of the Danish Viking Kings, Sven Estridsen, died in a.d. 1074 and is entombed in Roskilde Cathedral with other Danish kings and queens. Sven's mother, Estrid, is entombed in a pillar across the chancel. However, while there is no reasonable doubt about the identity of Sven, there have been doubts among historians whether the woman entombed was indeed Estrid. To shed light on this problem, we have extracted and analysed mitochondrial DNA (mtDNA) from pulp of teeth from each of the two royals. Four overlapping DNA-fragments covering about 400bp of hypervariable region 1 (HVR-1) of the D-loop were PCR amplified, cloned and a number of clones with each segment were sequenced. Also a segment containing the H/non-H specific nucleotide 7028 was sequenced. Consensus sequences were determined and D-loop results were replicated in an independent laboratory. This allowed the assignment of King Sven Estridsen to haplogroup H; Estrid's sequence differed from that of Sven at two positions in HVR-1, 16093T-->C and 16304T-->C, indicating that she belongs to subgroup H5a. Given the maternal inheritance of mtDNA, offspring will have the same mtDNA sequence as their mother with the exception of rare cases where the sequence has been altered by a germ line mutation. Therefore, the observation of two sequence differences makes it highly unlikely that the entombed woman was the mother of Sven. In addition, physical examination of the skeleton and the teeth strongly indicated that this woman was much younger (approximately 35 years) at the time of death than the 70 years history records tell. Although the entombed woman cannot be the Estrid, she may well be one of Sven's two daughters-in-law who were also called Estrid and who both became queens.

  15. Quantitative PCR analysis of diepoxybutane and epihalohydrin damage to nuclear versus mitochondrial DNA

    Energy Technology Data Exchange (ETDEWEB)

    LaRiviere, Frederick J. [Department of Chemistry, Washington and Lee University, Lexington, VA 24450 (United States); Newman, Adam G.; Watts, Megan L.; Bradley, Sharonda Q.; Juskewitch, Justin E. [Department of Chemistry, Colby College, 5757 Mayflower Hill Drive, Waterville, ME 04901 (United States); Greenwood, Paul G. [Department of Biology, Colby College, Waterville, ME 04901 (United States); Millard, Julie T., E-mail: jtmillar@colby.edu [Department of Chemistry, Colby College, 5757 Mayflower Hill Drive, Waterville, ME 04901 (United States)

    2009-05-12

    The bifunctional alkylating agents diepoxybutane (DEB) and epichlorohydrin (ECH) are linked to the elevated incidence of certain cancers among workers in the synthetic polymer industry. Both compounds form interstrand cross-links within duplex DNA, an activity suggested to contribute to their cytotoxicity. To assess the DNA targeting of these compounds in vivo, we assayed for damage within chicken erythro-progenitor cells at three different sites: one within mitochondrial DNA, one within expressed nuclear DNA, and one within unexpressed nuclear DNA. We determined the degree of damage at each site via a quantitative polymerase chain reaction, which compares amplification of control, untreated DNA to that from cells exposed to the agent in question. We found that ECH and the related compound epibromohydrin preferentially target nuclear DNA relative to mitochondrial DNA, whereas DEB reacts similarly with the two genomes. Decreased reactivity of the mitochondrial genome could contribute to the reduced apoptotic potential of ECH relative to DEB. Additionally, formation of lesions by all agents occurred at comparable levels for unexpressed and expressed nuclear loci, suggesting that alkylation is unaffected by the degree of chromatin condensation.

  16. Quantitative PCR analysis of diepoxybutane and epihalohydrin damage to nuclear versus mitochondrial DNA

    International Nuclear Information System (INIS)

    LaRiviere, Frederick J.; Newman, Adam G.; Watts, Megan L.; Bradley, Sharonda Q.; Juskewitch, Justin E.; Greenwood, Paul G.; Millard, Julie T.

    2009-01-01

    The bifunctional alkylating agents diepoxybutane (DEB) and epichlorohydrin (ECH) are linked to the elevated incidence of certain cancers among workers in the synthetic polymer industry. Both compounds form interstrand cross-links within duplex DNA, an activity suggested to contribute to their cytotoxicity. To assess the DNA targeting of these compounds in vivo, we assayed for damage within chicken erythro-progenitor cells at three different sites: one within mitochondrial DNA, one within expressed nuclear DNA, and one within unexpressed nuclear DNA. We determined the degree of damage at each site via a quantitative polymerase chain reaction, which compares amplification of control, untreated DNA to that from cells exposed to the agent in question. We found that ECH and the related compound epibromohydrin preferentially target nuclear DNA relative to mitochondrial DNA, whereas DEB reacts similarly with the two genomes. Decreased reactivity of the mitochondrial genome could contribute to the reduced apoptotic potential of ECH relative to DEB. Additionally, formation of lesions by all agents occurred at comparable levels for unexpressed and expressed nuclear loci, suggesting that alkylation is unaffected by the degree of chromatin condensation.

  17. Mt-rps3 is an ancient gene which provides insight into the evolution of fungal mitochondrial genomes.

    Science.gov (United States)

    Korovesi, Artemis G; Ntertilis, Maria; Kouvelis, Vassili N

    2018-05-12

    The nuclear ribosomal protein S3 (Rps3) is implicated in the assembly of the ribosomal small subunit. Fungi and plants present a gene copy in their mitochondrial (mt) genomes. An analysis of 303 complete fungal mt genomes showed that, when rps3 is found, it is either a free-standing gene or an anchored gene within the omega intron of the rnl gene. Early divergent fungi, Basidiomycota and all yeasts but the CTG group belong to the first case, and Pezizomycotina to the second. Its position, size and genetic code employed are conserved within species of the same Order. Size variability is attributed to different number of repeats. These repeats consist of AT-rich sequences. MtRps3 proteins lack the KH domain, necessary for binding to rRNA, in their N-terminal region. Their C-terminal region is conserved in all Domains of life. Phylogenetic analysis showed that nuclear and mt Rps3 proteins are descendants of archaeal and a-proteobacterial homologues, respectively. Thus, fungal mt-rps3 gene is an ancient gene which evolved within the endosymbiotic model and presents different evolutionary routes: (a) coming from a-proteobacteria, it was relocated to another region of the mt genome, (b) via its insertion to the omega intron, it was transferred to the nucleus and/or got lost, and (c) it was re-routed to the mt genome again. Today, Basidiomycota and Saccharomycetales seem to follow the first evolutionary route and almost all Pezizomycotina support the second scenario with their exceptions being the result of the third scenario, i.e., the gene's re-entry to the mt genome. Copyright © 2018. Published by Elsevier Inc.

  18. Thymidine kinase 2 (H126N) knockin mice show the essential role of balanced deoxynucleotide pools for mitochondrial DNA maintenance

    OpenAIRE

    Akman, Hasan O.; Dorado, Beatriz; López, Luis C.; García-Cazorla, Ángeles; Vilà, Maya R.; Tanabe, Lauren M.; Dauer, William T.; Bonilla, Eduardo; Tanji, Kurenai; Hirano, Michio

    2008-01-01

    Mitochondrial DNA (mtDNA) depletion syndrome (MDS), an autosomal recessive condition, is characterized by variable organ involvement with decreased mtDNA copy number and activities of respiratory chain enzymes in affected tissues. MtDNA depletion has been associated with mutations in nine autosomal genes, including thymidine kinase (TK2), which encodes a ubiquitous mitochondrial protein. To study the pathogenesis of TK2-deficiency, we generated mice harboring an H126N Tk2 mutation. Homozygous...

  19. Lack of mitochondrial MutS homolog 1 in Toxoplasma gondii disrupts maintenance and fidelity of mitochondrial DNA and reveals metabolic plasticity.

    Directory of Open Access Journals (Sweden)

    Tamila Garbuz

    Full Text Available The importance of maintaining the fidelity of the mitochondrial genome is underscored by the presence of various repair pathways within this organelle. Presumably, the repair of mitochondrial DNA would be of particular importance in organisms that possess only a single mitochondrion, like the human pathogens Plasmodium falciparum and Toxoplasma gondii. Understanding the machinery that maintains mitochondrial DNA in these parasites is of particular relevance, as mitochondrial function is a validated and effective target for anti-parasitic drugs. We previously determined that the Toxoplasma MutS homolog TgMSH1 localizes to the mitochondrion. MutS homologs are key components of the nuclear mismatch repair system in mammalian cells, and both yeast and plants possess MutS homologs that localize to the mitochondria where they regulate DNA stability. Here we show that the lack of TgMSH1 results in accumulation of single nucleotide variations in mitochondrial DNA and a reduction in mitochondrial DNA content. Additionally, parasites lacking TgMSH1 function can survive treatment with the cytochrome b inhibitor atovaquone. While the Tgmsh1 knockout strain has several missense mutations in cytochrome b, none affect amino acids known to be determinants of atovaquone sensitivity and atovaquone is still able to inhibit electron transport in the Tgmsh1 mutants. Furthermore, culture of Tgmsh1 mutant in the presence atovaquone leads to parasites with enhanced atovaquone resistance and complete shutdown of respiration. Thus, parasites lacking TgMSH1 overcome the disruption of mitochondrial DNA by adapting their physiology allowing them to forgo the need for oxidative phosphorylation. Consistent with this idea, the Tgmsh1 mutant is resistant to mitochondrial inhibitors with diverse targets and exhibits reduced ability to grow in the absence of glucose. This work shows TgMSH1 as critical for the maintenance and fidelity of the mitochondrial DNA in Toxoplasma

  20. mtDNA depletion myopathy: elucidation of the tissue specificity in the mitochondrial thymidine kinase (TK2) deficiency.

    Science.gov (United States)

    Saada, Ann; Shaag, Avraham; Elpeleg, Orly

    2003-05-01

    Decreased mitochondrial thymidine kinase (TK2) activity is associated with mitochondrial DNA (mtDNA) depletion and respiratory chain dysfunction and is manifested by isolated, fatal skeletal myopathy. Other tissues such as liver, brain, heart, and skin remain unaffected throughout the patients' life. In order to elucidate the mechanism of tissue specificity in the disease we have investigated the expression of the mitochondrial deoxynucleotide carrier, the mtDNA content and the activity of TK2 in mitochondria of various tissues. Our results suggest that low basal TK2 activity combined with a high requirement for mitochondrial encoded proteins in muscle predispose this tissue to the devastating effect of TK2 deficiency.

  1. Method for assessing damage to mitochondrial DNA caused by radiation and epichlorohydrin

    International Nuclear Information System (INIS)

    Singh, G.; Hauswirth, W.W.; Ross, W.E.; Neims, A.H.

    1985-01-01

    This paper describes a rapid and reliable method for quantification of damage to mitochondrial DNA (mtDNA), especially strand breaks. The degree of damage to mtDNA is assessed by the proportion of physical forms (i.e., supercoiled versus open-circular and linear forms) upon agarose gel electrophoresis, blotting, and visualization by hybridization with [ 32 P]mtDNA probes. The use of a radiolabeled probe is a crucial step in the procedure because it provides both a means to quantify by radioautography and to obtain the mtDNA specificity required to eliminate misinterpretation due to nuclear DNA contamination. To demonstrate the utility of this technique, X-irradiation and epichlorohydrin are shown to damage both isolated mtDNA and mtDNA in whole cells in a dose-dependent fashion

  2. Mitochondrial DNA depletion syndrome presenting with ataxia and ...

    African Journals Online (AJOL)

    The patient presented to Cairo University Pediatric Hospital with the clinical suspicion of mitochondrial encephalomyopathy. Histochemical and biochemical studies of the respiratory chain complexes were performed on the muscle biopsy specimen from the patient. Molecular diagnosis was done by quantitative radioactive ...

  3. Mitochondrial DNA deletion and impairment of mitochondrial biogenesis are mediated by reactive oxygen species in ionizing radiation-induced premature senescence

    International Nuclear Information System (INIS)

    Eom, Hyeon Soo; Jung, U Hee; Jo, Sung Kee; Kim, Young Sang

    2011-01-01

    Mitochondrial DNA (mtDNA) deletion is a well-known marker for oxidative stress and aging, and contributes to harmful effects in cultured cells and animal tissues. mtDNA biogenesis genes (NRF-1, TFAM) are essential for the maintenance of mtDNA, as well as the transcription and replication of mitochondrial genomes. Considering that oxidative stress is known to affect mitochondrial biogenesis, we hypothesized that ionizing radiation (IR)-induced reactive oxygen species (ROS) causes mtDNA deletion by modulating the mitochondrial biogenesis, thereby leading to cellular senescence. Therefore, we examined the effects of IR on ROS levels, cellular senescence, mitochondrial biogenesis, and mtDNA deletion in IMR-90 human lung fibroblast cells. Young IMR-90 cells at population doubling (PD) 39 were irradiated at 4 or 8 Gy. Old cells at PD55, and H2O2-treated young cells at PD 39, were compared as a positive control. The IR increased the intracellular ROS level, senescence-associated β-galactosidase (SA-β-gal) activity, and mtDNA common deletion (4977 bp), and it decreased the mRNA expression of NRF-1 and TFAM in IMR-90 cells. Similar results were also observed in old cells (PD 55) and H 2 O 2 -treated young cells. To confirm that a increase in ROS level is essential for mtDNA deletion and changes of mitochondrial biogenesis in irradiated cells, the effects of N-acetylcysteine (NAC) were examined. In irradiated and H 2 O 2 -treated cells, 5 mM NAC significantly attenuated the increases of ROS, mtDNA deletion, and SA-β-gal activity, and recovered from decreased expressions of NRF-1 and TFAM mRNA. These results suggest that ROS is a key cause of IR-induced mtDNA deletion, and the suppression of the mitochondrial biogenesis gene may mediate this process.

  4. Mitochondrial DNA deletion and impairment of mitochondrial biogenesis are mediated by reactive oxygen species in ionizing radiation-induced premature senescence

    Energy Technology Data Exchange (ETDEWEB)

    Eom, Hyeon Soo; Jung, U Hee; Jo, Sung Kee [Radiation Biotechnology Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Young Sang [College of Natural Sciences, Chungnam National University, Daejeon (Korea, Republic of)

    2011-09-15

    Mitochondrial DNA (mtDNA) deletion is a well-known marker for oxidative stress and aging, and contributes to harmful effects in cultured cells and animal tissues. mtDNA biogenesis genes (NRF-1, TFAM) are essential for the maintenance of mtDNA, as well as the transcription and replication of mitochondrial genomes. Considering that oxidative stress is known to affect mitochondrial biogenesis, we hypothesized that ionizing radiation (IR)-induced reactive oxygen species (ROS) causes mtDNA deletion by modulating the mitochondrial biogenesis, thereby leading to cellular senescence. Therefore, we examined the effects of IR on ROS levels, cellular senescence, mitochondrial biogenesis, and mtDNA deletion in IMR-90 human lung fibroblast cells. Young IMR-90 cells at population doubling (PD) 39 were irradiated at 4 or 8 Gy. Old cells at PD55, and H2O2-treated young cells at PD 39, were compared as a positive control. The IR increased the intracellular ROS level, senescence-associated {beta}-galactosidase (SA-{beta}-gal) activity, and mtDNA common deletion (4977 bp), and it decreased the mRNA expression of NRF-1 and TFAM in IMR-90 cells. Similar results were also observed in old cells (PD 55) and H{sub 2}O{sub 2}-treated young cells. To confirm that a increase in ROS level is essential for mtDNA deletion and changes of mitochondrial biogenesis in irradiated cells, the effects of N-acetylcysteine (NAC) were examined. In irradiated and H{sub 2}O{sub 2}-treated cells, 5 mM NAC significantly attenuated the increases of ROS, mtDNA deletion, and SA-{beta}-gal activity, and recovered from decreased expressions of NRF-1 and TFAM mRNA. These results suggest that ROS is a key cause of IR-induced mtDNA deletion, and the suppression of the mitochondrial biogenesis gene may mediate this process.

  5. Mitochondrial DNA damage and oxidative damage in HL-60 cells exposed to 900 MHz radiofrequency fields

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yulong; Zong, Lin; Gao, Zhen [School of Public Health, Soochow University, Suzhou, Jiangsu Province (China); Zhu, Shunxing [Laboratory Animal Center, Nantong University, Nantong, Jiangsu Province (China); Tong, Jian [School of Public Health, Soochow University, Suzhou, Jiangsu Province (China); Cao, Yi, E-mail: yicao@suda.edu.cn [School of Public Health, Soochow University, Suzhou, Jiangsu Province (China)

    2017-03-15

    Highlights: • Increased reactive oxygen species. • Decreased mitochondrial transcription Factor A and polymerase gamma. • Decreased mitochondrial transcripts (ND1 and 16S) and mtDNA copy number. • Increased 8-hydroxy-2′deoxyguanosine. • Decreased adenosine triphosphate. - Abstract: HL-60 cells, derived from human promyelocytic leukemia, were exposed to continuous wave 900 MHz radiofrequency fields (RF) at 120 μW/cm{sup 2} power intensity for 4 h/day for 5 consecutive days to examine whether such exposure is capable damaging the mitochondrial DNA (mtDNA) mediated through the production of reactive oxygen species (ROS). In addition, the effect of RF exposure was examined on 8-hydroxy-2′-dexoyguanosine (8-OHdG) which is a biomarker for oxidative damage and on the mitochondrial synthesis of adenosine triphosphate (ATP) which is the energy required for cellular functions. The results indicated a significant increase in ROS and significant decreases in mitochondrial transcription factor A, mtDNA polymerase gamma, mtDNA transcripts and mtDNA copy number in RF-exposed cells compared with those in sham-exposed control cells. In addition, there was a significant increase in 8-OHdG and a significant decrease in ATP in RF-exposed cells. The response in positive control cells exposed to gamma radiation (GR, which is also known to induce ROS) was similar to those in RF-exposed cells. Thus, the overall data indicated that RF exposure was capable of inducing mtDNA damage mediated through ROS pathway which also induced oxidative damage. Prior-treatment of RF- and GR-exposed the cells with melatonin, a well-known free radical scavenger, reversed the effects observed in RF-exposed cells.

  6. Use DNA to learn from the past: how modern and ancient DNA studies may help reveal the past and predict the future distribution of species

    Science.gov (United States)

    Edwards, M. E.; Alsos, I. G.; Sjögren, P.; Coissac, E.; Gielly, L.; Yoccoz, N.; Føreid, M. K.; Taberlet, P.

    2015-12-01

    Knowledge of how climate change affected species distribution in the past may help us predict the effect of ongoing environmental changes. We explore how the use of modern (AFLP fingerprinting techniques) and ancient DNA (metabarcoding P6 loop of chloroplast DNA) help to reveal past distribution of vascular plant species, dispersal processes, and effect of species traits. Based on studies of modern DNA combined with species distribution models, we show the dispersal routes and barriers to dispersal throughout the circumarctic/circumboreal region, likely dispersal vectors, the cost of dispersal in term of loss of genetic diversity, and how these relates to species traits, dispersal distance, and size of colonized region. We also estimate the expected future distribution and loss of genetic diversity and show how this relates to life form and adaptations to dispersal. To gain more knowledge on time lags in past range change events, we rely on palaeorecords. Current data on past distribution are limited by the taxonomic and time resolution of macrofossil and pollen records. We show how this may be improved by studying ancient DNA of lake sediments. DNA of lake sediments recorded about half of the flora surrounding the lake. Compared to macrofossil, the taxonomic resolution is similar but the detection rate is considerable improved. By taking into account main determinants of founder effect, dispersal vectors, and dispersal lags, we may improve our ability to forecast effects of climate change, whereas more studies on ancient DNA may provide us with knowledge on distribution time lags.

  7. Mitochondrial Disease

    OpenAIRE

    Bulent Kurt; Turgut Topal

    2013-01-01

    Mitochondria are the major energy source of cells. Mitochondrial disease occurs due to a defect in mitochondrial energy production. A valuable energy production in mitochondria depend a healthy interconnection between nuclear and mitochondrial DNA. A mutation in nuclear or mitochondrial DNA may cause abnormalities in ATP production and single or multiple organ dysfunctions, secondarily. In this review, we summarize mitochondrial physiology, mitochondrial genetics, and clinical expression and ...

  8. Mitochondrial-targeted DNA delivery using a DF-MITO-Porter, an innovative nano carrier with cytoplasmic and mitochondrial fusogenic envelopes

    International Nuclear Information System (INIS)

    Yamada, Yuma; Kawamura, Eriko; Harashima, Hideyoshi

    2012-01-01

    Mitochondrial gene therapy has the potential for curing a variety of diseases that are associated with mitochondrial DNA mutations and/or defects. To achieve this, it will be necessary to deliver therapeutic agents into the mitochondria in diseased cells. A number of mitochondrial drug delivery systems have been reported to date. However, reports of mitochondrial-targeted DNA delivery are limited. To achieve this, the therapeutic agent must be taken up by the cell (1), after which, the multi-processes associated with intracellular trafficking must be sophisticatedly regulated so as to release the agent from the endosome and deliver it to the cytosol (2) and to pass through the mitochondrial membrane (3). We report herein on the mitochondrial delivery of oligo DNA as a model therapeutic using a Dual Function (DF)-MITO-Porter, an innovative nano carrier designed for mitochondrial delivery. The critical structural elements of the DF-MITO-Porter include mitochondria-fusogenic inner envelopes and endosome-fusogenic outer envelopes, modified with octaarginine which greatly assists in cellular uptake. Inside the cell, the carrier passes through the endosomal and mitochondrial membranes via step-wise membrane fusion. When the oligo DNA was packaged in the DF-MITO-Porter, cellular uptake efficiency was strongly enhanced. Intracellular observation using confocal laser scanning microscopy showed that the DF-MITO-Porter was effectively released from endosomes. Moreover, the findings confirmed that the mitochondrial targeting activity of the DF-MITO-Porter was significantly higher than that of a carrier without outer endosome-fusogenic envelopes. These results support the conclusion that mitochondrial-targeted DNA delivery using a DF-MITO-Porter can be achieved when intracellular trafficking is optimally regulated.

  9. Mitochondrial-targeted DNA delivery using a DF-MITO-Porter, an innovative nano carrier with cytoplasmic and mitochondrial fusogenic envelopes

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Yuma; Kawamura, Eriko; Harashima, Hideyoshi, E-mail: harasima@pharm.hokudai.ac.jp [Hokkaido University, Laboratory for Molecular Design of Pharmaceutics, Faculty of Pharmaceutical Sciences (Japan)

    2012-08-15

    Mitochondrial gene therapy has the potential for curing a variety of diseases that are associated with mitochondrial DNA mutations and/or defects. To achieve this, it will be necessary to deliver therapeutic agents into the mitochondria in diseased cells. A number of mitochondrial drug delivery systems have been reported to date. However, reports of mitochondrial-targeted DNA delivery are limited. To achieve this, the therapeutic agent must be taken up by the cell (1), after which, the multi-processes associated with intracellular trafficking must be sophisticatedly regulated so as to release the agent from the endosome and deliver it to the cytosol (2) and to pass through the mitochondrial membrane (3). We report herein on the mitochondrial delivery of oligo DNA as a model therapeutic using a Dual Function (DF)-MITO-Porter, an innovative nano carrier designed for mitochondrial delivery. The critical structural elements of the DF-MITO-Porter include mitochondria-fusogenic inner envelopes and endosome-fusogenic outer envelopes, modified with octaarginine which greatly assists in cellular uptake. Inside the cell, the carrier passes through the endosomal and mitochondrial membranes via step-wise membrane fusion. When the oligo DNA was packaged in the DF-MITO-Porter, cellular uptake efficiency was strongly enhanced. Intracellular observation using confocal laser scanning microscopy showed that the DF-MITO-Porter was effectively released from endosomes. Moreover, the findings confirmed that the mitochondrial targeting activity of the DF-MITO-Porter was significantly higher than that of a carrier without outer endosome-fusogenic envelopes. These results support the conclusion that mitochondrial-targeted DNA delivery using a DF-MITO-Porter can be achieved when intracellular trafficking is optimally regulated.

  10. Frequent occurrence of mitochondrial DNA mutations in Barrett's metaplasia without the presence of dysplasia.

    Directory of Open Access Journals (Sweden)

    Soong Lee

    Full Text Available BACKGROUND: Barrett's esophagus (BE is one of the most common premalignant lesions and can progress to esophageal adenocarcinoma (EA. The numerous molecular events may play a role in the neoplastic transformation of Barrett's mucosa such as the change of DNA ploidy, p53 mutation and alteration of adhesion molecules. However, the molecular mechanism of the progression of BE to EA remains unclear and most studies of mitochondrial DNA (mtDNA mutations in BE have performed on BE with the presence of dysplasia. METHODS/FINDINGS: Thus, the current study is to investigate new molecular events (Barrett's esophageal tissue-specific-mtDNA alterations/instabilities in mitochondrial genome and causative factors for their alterations using the corresponding adjacent normal mucosal tissue (NT and tissue (BT from 34 patients having Barrett's metaplasia without the presence of dysplasia. Eighteen patients (53% exhibited mtDNA mutations which were not found in adjacent NT. mtDNA copy number was about 3 times higher in BT than in adjacent NT. The activity of the mitochondrial respiratory chain enzyme complexes in tissues from Barrett's metaplasia without the presence of dysplasia was impaired. Reactive oxygen species (ROS level in BT was significantly higher than those in corresponding samples. CONCLUSION/SIGNIFICANCE: High ROS level in BT may contribute to the development of mtDNA mutations, which may play a crucial role in disease progression and tumorigenesis in BE.

  11. Mitochondrial DNA plays an equal role in influencing female and male longevity in centenarians.

    Science.gov (United States)

    He, Yong-Han; Lu, Xiang; Tian, Jiao-Yang; Yan, Dong-Jing; Li, Yu-Chun; Lin, Rong; Perry, Benjamin; Chen, Xiao-Qiong; Yu, Qin; Cai, Wang-Wei; Kong, Qing-Peng

    2016-10-01

    The mitochondrion is a double membrane-bound organelle which plays important functional roles in aging and many other complex phenotypes. Transmission of the mitochondrial genome in the matrilineal line causes the evolutionary selection sieve only in females. Theoretically, beneficial or neutral variations are more likely to accumulate and be retained in the female mitochondrial genome during evolution, which may be an initial trigger of gender dimorphism in aging. The asymmetry of evolutionary processes between gender could lead to males and females aging in different ways. If so, gender specific variation loads could be an evolutionary result of maternal heritage of mitochondrial genomes, especially in centenarians who live to an extreme age and are considered as good models for healthy aging. Here, we tested whether the mitochondrial variation loads were associated with altered aging patterns by investigating the mtDNA haplogroup distribution and genetic diversity between female and male centenarians. We found no evidence of differences in aging patterns between genders in centenarians. Our results indicate that the evolutionary consequence of gender dimorphism in mitochondrial genomes is not a factor in the altered aging patterns in human, and that mitochondrial DNA contributes equally to longevity in males and females. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Global DNA methylation synergistically regulates the nuclear and mitochondrial genomes in glioblastoma cells.

    Science.gov (United States)

    Sun, Xin; Johnson, Jacqueline; St John, Justin C

    2018-05-02

    Replication of mitochondrial DNA is strictly regulated during differentiation and development allowing each cell type to acquire its required mtDNA copy number to meet its specific needs for energy. Undifferentiated cells establish the mtDNA set point, which provides low numbers of mtDNA copy but sufficient template for replication once cells commit to specific lineages. However, cancer cells, such as those from the human glioblastoma multiforme cell line, HSR-GBM1, cannot complete differentiation as they fail to enforce the mtDNA set point and are trapped in a 'pseudo-differentiated' state. Global DNA methylation is likely to be a major contributing factor, as DNA demethylation treatments promote differentiation of HSR-GBM1 cells. To determine the relationship between DNA methylation and mtDNA copy number in cancer cells, we applied whole genome MeDIP-Seq and RNA-Seq to HSR-GBM1 cells and following their treatment with the DNA demethylation agents 5-azacytidine and vitamin C. We identified key methylated regions modulated by the DNA demethylation agents that also induced synchronous changes to mtDNA copy number and nuclear gene expression. Our findings highlight the control exerted by DNA methylation on the expression of key genes, the regulation of mtDNA copy number and establishment of the mtDNA set point, which collectively contribute to tumorigenesis.

  13. Novel large-range mitochondrial DNA deletions and fatal multisystemic disorder with prominent hepatopathy

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, Marzia; Rizza, Teresa; Verrigni, Daniela [Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Diseases, ' Bambino Gesu' Children' s Hospital, Rome (Italy); Martinelli, Diego [Division of Metabolism, ' Bambino Gesu' Children' s Hospital, Rome (Italy); Tozzi, Giulia; Torraco, Alessandra; Piemonte, Fiorella [Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Diseases, ' Bambino Gesu' Children' s Hospital, Rome (Italy); Dionisi-Vici, Carlo [Division of Metabolism, ' Bambino Gesu' Children' s Hospital, Rome (Italy); Nobili, Valerio [Gastroenterology and Liver Unit, ' Bambino Gesu' Children' s Hospital, Rome (Italy); Francalanci, Paola; Boldrini, Renata; Callea, Francesco [Dept. Pathology, ' Bambino Gesu' Children' s Hospital, Rome (Italy); Santorelli, Filippo Maria [UOC Neurogenetica e Malattie Neuromuscolari, Fondazione Stella Maris, Pisa (Italy); Bertini, Enrico [Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Diseases, ' Bambino Gesu' Children' s Hospital, Rome (Italy); and others

    2011-11-18

    Highlights: Black-Right-Pointing-Pointer Expanded array of mtDNA deletions. Black-Right-Pointing-Pointer Pearson syndrome with prominent hepatopathy associated with single mtDNA deletions. Black-Right-Pointing-Pointer Detection of deletions in fibroblasts and blood avoids muscle and liver biopsy. Black-Right-Pointing-Pointer Look for mtDNA deletions before to study nuclear genes related to mtDNA depletion. -- Abstract: Hepatic involvement in mitochondrial cytopathies rarely manifests in adulthood, but is a common feature in children. Multiple OXPHOS enzyme defects in children with liver involvement are often associated with dramatically reduced amounts of mtDNA. We investigated two novel large scale deletions in two infants with a multisystem disorder and prominent hepatopathy. Amount of mtDNA deletions and protein content were measured in different post-mortem tissues. The highest levels of deleted mtDNA were in liver, kidney, pancreas of both patients. Moreover, mtDNA deletions were detected in cultured skin fibroblasts in both patients and in blood of one during life. Biochemical analysis showed impairment of mainly complex I enzyme activity. Patients manifesting multisystem disorders in childhood may harbour rare mtDNA deletions in multiple tissues. For these patients, less invasive blood specimens or cultured fibroblasts can be used for molecular diagnosis. Our data further expand the array of deletions in the mitochondrial genomes in association with liver failure. Thus analysis of mtDNA should be considered in the diagnosis of childhood-onset hepatopathies.

  14. Novel large-range mitochondrial DNA deletions and fatal multisystemic disorder with prominent hepatopathy

    International Nuclear Information System (INIS)

    Bianchi, Marzia; Rizza, Teresa; Verrigni, Daniela; Martinelli, Diego; Tozzi, Giulia; Torraco, Alessandra; Piemonte, Fiorella; Dionisi-Vici, Carlo; Nobili, Valerio; Francalanci, Paola; Boldrini, Renata; Callea, Francesco; Santorelli, Filippo Maria; Bertini, Enrico

    2011-01-01

    Highlights: ► Expanded array of mtDNA deletions. ► Pearson syndrome with prominent hepatopathy associated with single mtDNA deletions. ► Detection of deletions in fibroblasts and blood avoids muscle and liver biopsy. ► Look for mtDNA deletions before to study nuclear genes related to mtDNA depletion. -- Abstract: Hepatic involvement in mitochondrial cytopathies rarely manifests in adulthood, but is a common feature in children. Multiple OXPHOS enzyme defects in children with liver involvement are often associated with dramatically reduced amounts of mtDNA. We investigated two novel large scale deletions in two infants with a multisystem disorder and prominent hepatopathy. Amount of mtDNA deletions and protein content were measured in different post-mortem tissues. The highest levels of deleted mtDNA were in liver, kidney, pancreas of both patients. Moreover, mtDNA deletions were detected in cultured skin fibroblasts in both patients and in blood of one during life. Biochemical analysis showed impairment of mainly complex I enzyme activity. Patients manifesting multisystem disorders in childhood may harbour rare mtDNA deletions in multiple tissues. For these patients, less invasive blood specimens or cultured fibroblasts can be used for molecular diagnosis. Our data further expand the array of deletions in the mitochondrial genomes in association with liver failure. Thus analysis of mtDNA should be considered in the diagnosis of childhood-onset hepatopathies.

  15. Targeted impairment of thymidine kinase 2 expression in cells induces mitochondrial DNA depletion and reveals molecular mechanisms of compensation of mitochondrial respiratory activity

    International Nuclear Information System (INIS)

    Villarroya, Joan; Lara, Mari-Carmen; Dorado, Beatriz; Garrido, Marta; Garcia-Arumi, Elena; Meseguer, Anna; Hirano, Michio; Vila, Maya R.

    2011-01-01

    Highlights: → We impaired TK2 expression in Ost TK1 - cells via siRNA-mediated interference (TK2 - ). → TK2 impairment caused severe mitochondrial DNA (mtDNA) depletion in quiescent cells. → Despite mtDNA depletion, TK2 - cells show high cytochrome oxidase activity. → Depletion of mtDNA occurs without imbalance in the mitochondrial dNTP pool. → Nuclear-encoded ENT1, DNA-pol γ, TFAM and TP gene expression is lowered in TK2 - cells. -- Abstract: The mitochondrial DNA (mtDNA) depletion syndrome comprises a clinically heterogeneous group of diseases characterized by reductions of the mtDNA abundance, without associated point mutations or rearrangements. We have developed the first in vitro model to study of mtDNA depletion due to reduced mitochondrial thymidine kinase 2 gene (TK2) expression in order to understand the molecular mechanisms involved in mtDNA depletion syndrome due to TK2 mutations. Small interfering RNA targeting TK2 mRNA was used to decrease TK2 expression in Ost TK1 - cells, a cell line devoid of endogenous thymidine kinase 1 (TK1). Stable TK2-deficient cell lines showed a reduction of TK2 levels close to 80%. In quiescent conditions, TK2-deficient cells showed severe mtDNA depletion, also close to 80% the control levels. However, TK2-deficient clones showed increased cytochrome c oxidase activity, higher cytochrome c oxidase subunit I transcript levels and higher subunit II protein expression respect to control cells. No alterations of the deoxynucleotide pools were found, whereas a reduction in the expression of genes involved in nucleoside/nucleotide homeostasis (human equilibrative nucleoside transporter 1, thymidine phosphorylase) and mtDNA maintenance (DNA-polymerase γ, mitochondrial transcription factor A) was observed. Our findings highlight the importance of cellular compensatory mechanisms that enhance the expression of respiratory components to ensure respiratory activity despite profound depletion in mtDNA levels.

  16. Liver ultrastructural morphology and mitochondrial DNA levels in HIV/hepatitis C virus coinfection: no evidence of mitochondrial damage with highly active antiretroviral therapy.

    Science.gov (United States)

    Matsukura, Motoi; Chu, Fanny F S; Au, May; Lu, Helen; Chen, Jennifer; Rietkerk, Sonja; Barrios, Rolando; Farley, John D; Montaner, Julio S; Montessori, Valentina C; Walker, David C; Côté, Hélène C F

    2008-06-19

    Liver mitochondrial toxicity is a concern, particularly in HIV/hepatitis C virus (HCV) coinfection. Liver biopsies from HIV/HCV co-infected patients, 14 ON-highly active antiretroviral therapy (HAART) and nine OFF-HAART, were assessed by electron microscopy quantitative morphometric analyses. Hepatocytes tended to be larger ON-HAART than OFF-HAART (P = 0.05), but mitochondrial volume, cristae density, lipid volume, mitochondrial DNA and RNA levels were similar. We found no evidence of increased mitochondrial toxicity in individuals currently on HAART, suggesting that concomitant HAART should not delay HCV therapy.

  17. Ancient genomics

    DEFF Research Database (Denmark)

    Der Sarkissian, Clio; Allentoft, Morten Erik; Avila Arcos, Maria del Carmen

    2015-01-01

    throughput of next generation sequencing platforms and the ability to target short and degraded DNA molecules. Many ancient specimens previously unsuitable for DNA analyses because of extensive degradation can now successfully be used as source materials. Additionally, the analytical power obtained...... by increasing the number of sequence reads to billions effectively means that contamination issues that have haunted aDNA research for decades, particularly in human studies, can now be efficiently and confidently quantified. At present, whole genomes have been sequenced from ancient anatomically modern humans...

  18. Differential mitochondrial DNA and gene expression in inherited retinal dysplasia in miniature Schnauzer dogs.

    Science.gov (United States)

    Appleyard, Greg D; Forsyth, George W; Kiehlbauch, Laura M; Sigfrid, Kristen N; Hanik, Heather L J; Quon, Anita; Loewen, Matthew E; Grahn, Bruce H

    2006-05-01

    To investigate the molecular basis of inherited retinal dysplasia in miniature Schnauzers. Retina and retinal pigment epithelial tissues were collected from canine subjects at the age of 3 weeks. Total RNA isolated from these tissues was reverse transcribed to make representative cDNA pools that were compared for differences in gene expression by using a subtractive hybridization technique referred to as representational difference analysis (RDA). Expression differences identified by RDA were confirmed and quantified by real-time reverse-transcription PCR. Mitochondrial morphology from leukocytes and skeletal muscle of normal and affected miniature Schnauzers was examined by transmission electron microscopy. RDA screening of retinal pigment epithelial cDNA identified differences in mRNA transcript coding for two mitochondrial (mt) proteins--cytochrome oxidase subunit 1 and NADH dehydrogenase subunit 6--in affected dogs. Contrary to expectations, these identified sequences did not contain mutations. Based on the implication of mt-DNA-encoded proteins by the RDA experiments we used real-time PCR to compare the relative amounts of mt-DNA template in white blood cells from normal and affected dogs. White blood cells of affected dogs contained less than 30% of the normal amount of two specific mtDNA sequences, compared with the content of the nuclear-encoded glyceraldehyde-3-phosphate dehydrogenase (GA-3-PDH) reference gene. Retina and RPE tissue from affected dogs had reduced mRNA transcript levels for the two mitochondrial genes detected in the RDA experiment. Transcript levels for another mtDNA-encoded gene as well as the nuclear-encoded mitochondrial Tfam transcription factor were reduced in these tissues in affected dogs. Mitochondria from affected dogs were reduced in number and size and were unusually electron dense. Reduced levels of nuclear and mitochondrial transcripts in the retina and RPE of miniature Schnauzers affected with retinal dysplasia suggest that

  19. Parental diabetes status reveals association of mitochondrial DNA haplogroup J1 with type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Wainstein Julio

    2009-06-01

    Full Text Available Abstract Background Although mitochondrial dysfunction is consistently manifested in patients with Type 2 Diabetes mellitus (T2DM, the association of mitochondrial DNA (mtDNA sequence variants with T2DM varies among populations. These differences might stem from differing environmental influences among populations. However, other potentially important considerations emanate from the very nature of mitochondrial genetics, namely the notable high degree of partitioning in the distribution of human mtDNA variants among populations, as well as the interaction of mtDNA and nuclear DNA-encoded factors working in concert to govern mitochondrial function. We hypothesized that association of mtDNA genetic variants with T2DM could be revealed while controlling for the effect of additional inherited factors, reflected in family history information. Methods To test this hypothesis we set out to investigate whether mtDNA genetic variants will be differentially associated with T2DM depending on the diabetes status of the parents. To this end, association of mtDNA genetic backgrounds (haplogroups with T2DM was assessed in 1055 Jewish patients with and without T2DM parents ('DP' and 'HP', respectively. Results Haplogroup J1 was found to be 2.4 fold under-represented in the 'HP' patients (p = 0.0035. These results are consistent with a previous observation made in Finnish T2DM patients. Moreover, assessing the haplogroup distribution in 'DP' versus 'HP' patients having diabetic siblings revealed that haplogroup J1 was virtually absent in the 'HP' group. Conclusion These results imply the involvement of inherited factors, which modulate the susceptibility of haplogroup J1 to T2DM.

  20. Increased mitochondrial DNA deletions and copy number in transfusion-dependent thalassemia

    Science.gov (United States)

    Calloway, Cassandra

    2016-01-01

    BACKGROUND. Iron overload is the primary cause of morbidity in transfusion-dependent thalassemia. Increase in iron causes mitochondrial dysfunction under experimental conditions, but the occurrence and significance of mitochondrial damage is not understood in patients with thalassemia. METHODS. Mitochondrial DNA (mtDNA) to nuclear DNA copy number (Mt/N) and frequency of the common 4977-bp mitochondrial deletion (ΔmtDNA4977) were quantified using a quantitative PCR assay on whole blood samples from 38 subjects with thalassemia who were receiving regular transfusions. RESULTS. Compared with healthy controls, Mt/N and ΔmtDNA4977 frequency were elevated in thalassemia (P = 0.038 and P 15 mg/g dry-weight or splenectomy, with the highest levels observed in subjects who had both risk factors (P = 0.003). Myocardial iron (MRI T2* 40/1 × 107 mtDNA, respectively (P = 0.025). Subjects with Mt/N values below the group median had significantly lower Matsuda insulin sensitivity index (5.76 ± 0.53) compared with the high Mt/N group (9.11 ± 0.95, P = 0.008). CONCLUSION. Individuals with transfusion-dependent thalassemia demonstrate age-related increase in mtDNA damage in leukocytes. These changes are markedly amplified by splenectomy and are associated with extrahepatic iron deposition. Elevated mtDNA damage in blood cells may predict the risk of iron-associated organ damage in thalassemia. FUNDING. This project was supported by Children’s Hospital & Research Center Oakland Institutional Research Award and by the National Center for Advancing Translational Sciences, NIH, through UCSF-CTSI grant UL1 TR000004. PMID:27583305

  1. MELAS syndrome, cardiomyopathy, rhabdomyolysis, and autism associated with the A3260G mitochondrial DNA mutation.

    Science.gov (United States)

    Connolly, Barbara S; Feigenbaum, Annette S J; Robinson, Brian H; Dipchand, Anne I; Simon, David K; Tarnopolsky, Mark A

    2010-11-12

    The A to G transition mutation at position 3260 of the mitochondrial genome is usually associated with cardiomyopathy and myopathy. One Japanese kindred reported the phenotype of mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS syndrome) in association with the A3260G mtDNA mutation. We describe the first Caucasian cases of MELAS syndrome associated with the A3260G mutation. Furthermore, this mutation was associated with exercise-induced rhabdomyolysis, hearing loss, seizures, cardiomyopathy, and autism in the large kindred. We conclude that the A3260G mtDNA mutation is associated with wide phenotypic heterogeneity with MELAS and other "classical" mitochondrial phenotypes being manifestations. Copyright © 2010 Elsevier Inc. All rights reserved.

  2. A unique DNA found in post-mitochondrial fraction from Ehrlich ascites tumor cells

    International Nuclear Information System (INIS)

    Guimaraes, R.C.; Bloch, D.P.

    1982-01-01

    A DNA found in post-mitochondrial fractions from Ehrlich ascites cells, comprising 0.2% of the total cellular DNA, is partially characterized. It appears in cytoplasmic homogenates as a 14.6 S molecule, and is eluted from hydroxyapatite with 0.24 M sodium phosphate buffer. Its Cs 2 SO 4 buoyant density is lower than Erlich ascites tumor nuclear DNA and it has low dG+dC content, as determined by chromatography of hydrolysates of 32 P-labelled DNA. It is enriched in sequences which reassociate rapidly in the presence of excess nuclear DNA. It can be used as promoter for DNA synthesis by an endogenous DNA-dependent DNA polymerase found in association with the post-mitochondrial preparations. It is found to be associated with newly incorporated radioactivity following incubation in vitro with labelled UTP. Its localization in situ has not yet been attempled. It is thought to represent viral A-type particle associated, or plasma membrane associated DNA. (author) [pt

  3. In vitro-reconstituted nucleoids can block mitochondrial DNA replication and transcription.

    Science.gov (United States)

    Farge, Géraldine; Mehmedovic, Majda; Baclayon, Marian; van den Wildenberg, Siet M J L; Roos, Wouter H; Gustafsson, Claes M; Wuite, Gijs J L; Falkenberg, Maria

    2014-07-10

    The mechanisms regulating the number of active copies of mtDNA are still unclear. A mammalian cell typically contains 1,000-10,000 copies of mtDNA, which are packaged into nucleoprotein complexes termed nucleoids. The main protein component of these structures is mitochondrial transcription factor A (TFAM). Here, we reconstitute nucleoid-like particles in vitro and demonstrate that small changes in TFAM levels dramatically impact the fraction of DNA molecules available for transcription and DNA replication. Compaction by TFAM is highly cooperative, and at physiological ratios of TFAM to DNA, there are large variations in compaction, from fully compacted nucleoids to naked DNA. In compacted nucleoids, TFAM forms stable protein filaments on DNA that block melting and prevent progression of the replication and transcription machineries. Based on our observations, we suggest that small variations in the TFAM-to-mtDNA ratio may be used to regulate mitochondrial gene transcription and DNA replication. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Genetic structure of European populations of Salmo salar L (Atlantic salmon) inferred from mitochondrial DNA

    DEFF Research Database (Denmark)

    Eg Nielsen, Einar; Hansen, Michael Møller; Loeschcke, V.

    1996-01-01

    The genetic relationships between the only natural population of Atlantic salmon (Salmo salar L.) in Denmark and seven other European salmon populations were studied using RFLP analysis of PCR amplified mitochondrial DNA segments. Six different haplotypes were detected by restriction enzyme...

  5. Archeogenetika. Mitochondriální DNA a migrace Homo sapiens

    Czech Academy of Sciences Publication Activity Database

    Černý, Viktor

    2010-01-01

    Roč. 11, - (2010), s. 13-17 ISSN 1213-1628 R&D Projects: GA ČR GA206/08/1587; GA MŠk ME 917 Institutional research plan: CEZ:AV0Z80020508 Keywords : archaeogenetics * migrations * mitochondrial DNA Subject RIV: AC - Archeology, Anthropology, Ethnology

  6. Is There Still Any Role for Oxidative Stress in Mitochondrial DNA-Dependent Aging?

    Directory of Open Access Journals (Sweden)

    Gábor Zsurka

    2018-03-01

    Full Text Available Recent deep sequencing data has provided compelling evidence that the spectrum of somatic point mutations in mitochondrial DNA (mtDNA in aging tissues lacks G > T transversion mutations. This fact cannot, however, be used as an argument for the missing contribution of reactive oxygen species (ROS to mitochondria-related aging because it is probably caused by the nucleotide selectivity of mitochondrial DNA polymerase γ (POLG. In contrast to point mutations, the age-dependent accumulation of mitochondrial DNA deletions is, in light of recent experimental data, still explainable by the segregation of mutant molecules generated by the direct mutagenic effects of ROS (in particular, of HO· radicals formed from H2O2 by a Fenton reaction. The source of ROS remains controversial, because the mitochondrial contribution to tissue ROS production is probably lower than previously thought. Importantly, in the discussion about the potential role of oxidative stress in mitochondria-dependent aging, ROS generated by inflammation-linked processes and the distribution of free iron also require careful consideration.

  7. Systematics of the Dioryctria abietella Species Group (Lepidoptera: Pyralidae) Based on Mitochondrial DNA Ann

    Science.gov (United States)

    G. Roux-Morabito; N.E. Gillette; A. Roques; L. Dormont; J. Stein; F.A.H. Sperling

    2008-01-01

    Coneworms of the genus Dioryctria Zeller include several serious pests of conifer seeds that are notoriously difficult to distinguish as species. We surveyed mitochondrial DNA variation within the abietella species group by sequencing 451 bp of cytochrome oxidase subunit 1 (COI) and 572 bp of cytochrome oxidase subunit 2 (COII...

  8. Packaging of single DNA molecules by the yeast mitochondrial protein Abf2p.

    Science.gov (United States)

    Brewer, Laurence R; Friddle, Raymond; Noy, Aleksandr; Baldwin, Enoch; Martin, Shelley S; Corzett, Michele; Balhorn, Rod; Baskin, Ronald J

    2003-10-01

    Mitochondrial and nuclear DNA are packaged by proteins in a very different manner. Although protein-DNA complexes called "nucleoids" have been identified as the genetic units of mitochondrial inheritance in yeast and man, little is known about their physical structure. The yeast mitochondrial protein Abf2p was shown to be sufficient to compact linear dsDNA, without the benefit of supercoiling, using optical and atomic force microscopy single molecule techniques. The packaging of DNA by Abf2p was observed to be very weak as evidenced by a fast Abf2p off-rate (k(off) = 0.014 +/- 0.001 s(-1)) and the extremely small forces (<0.6 pN) stabilizing the condensed protein-DNA complex. Atomic force microscopy images of individual complexes showed the 190-nm structures are loosely packaged relative to nuclear chromatin. This organization may leave mtDNA accessible for transcription and replication, while making it more vulnerable to damage.

  9. A rolling circle replication mechanism produces multimeric lariats of mitochondrial DNA in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Samantha C Lewis

    2015-02-01

    Full Text Available Mitochondrial DNA (mtDNA encodes respiratory complex subunits essential to almost all eukaryotes; hence respiratory competence requires faithful duplication of this molecule. However, the mechanism(s of its synthesis remain hotly debated. Here we have developed Caenorhabditis elegans as a convenient animal model for the study of metazoan mtDNA synthesis. We demonstrate that C. elegans mtDNA replicates exclusively by a phage-like mechanism, in which multimeric molecules are synthesized from a circular template. In contrast to previous mammalian studies, we found that mtDNA synthesis in the C. elegans gonad produces branched-circular lariat structures with multimeric DNA tails; we were able to detect multimers up to four mtDNA genome unit lengths. Further, we did not detect elongation from a displacement-loop or analogue of 7S DNA, suggesting a clear difference from human mtDNA in regard to the site(s of replication initiation. We also identified cruciform mtDNA species that are sensitive to cleavage by the resolvase RusA; we suggest these four-way junctions may have a role in concatemer-to-monomer resolution. Overall these results indicate that mtDNA synthesis in C. elegans does not conform to any previously documented metazoan mtDNA replication mechanism, but instead are strongly suggestive of rolling circle replication, as employed by bacteriophages. As several components of the metazoan mitochondrial DNA replisome are likely phage-derived, these findings raise the possibility that the rolling circle mtDNA replication mechanism may be ancestral among metazoans.

  10. Import of desired nucleic acid sequences using addressing motif of mitochondrial ribosomal 5S-rRNA for fluorescent in vivo hybridization of mitochondrial DNA and RNA.

    Science.gov (United States)

    Zelenka, Jaroslav; Alán, Lukáš; Jabůrek, Martin; Ježek, Petr

    2014-04-01

    Based on the matrix-addressing sequence of mitochondrial ribosomal 5S-rRNA (termed MAM), which is naturally imported into mitochondria, we have constructed an import system for in vivo targeting of mitochondrial DNA (mtDNA) or mt-mRNA, in order to provide fluorescence hybridization of the desired sequences. Thus DNA oligonucleotides were constructed, containing the 5'-flanked T7 RNA polymerase promoter. After in vitro transcription and fluorescent labeling with Alexa Fluor(®) 488 or 647 dye, we obtained the fluorescent "L-ND5 probe" containing MAM and exemplar cargo, i.e., annealing sequence to a short portion of ND5 mRNA and to the light-strand mtDNA complementary to the heavy strand nd5 mt gene (5'-end 21 base pair sequence). For mitochondrial in vivo fluorescent hybridization, HepG2 cells were treated with dequalinium micelles, containing the fluorescent probes, bringing the probes proximally to the mitochondrial outer membrane and to the natural import system. A verification of import into the mitochondrial matrix of cultured HepG2 cells was provided by confocal microscopy colocalizations. Transfections using lipofectamine or probes without 5S-rRNA addressing MAM sequence or with MAM only were ineffective. Alternatively, the same DNA oligonucleotides with 5'-CACC overhang (substituting T7 promoter) were transcribed from the tetracycline-inducible pENTRH1/TO vector in human embryonic kidney T-REx®-293 cells, while mitochondrial matrix localization after import of the resulting unlabeled RNA was detected by PCR. The MAM-containing probe was then enriched by three-order of magnitude over the natural ND5 mRNA in the mitochondrial matrix. In conclusion, we present a proof-of-principle for mitochondrial in vivo hybridization and mitochondrial nucleic acid import.

  11. Postglacial species displacement in Triturus newts deduced from asymmetrically introgressed mitochondrial DNA and ecological niche models

    Directory of Open Access Journals (Sweden)

    Wielstra Ben

    2012-08-01

    Full Text Available Abstract Background If the geographical displacement of one species by another is accompanied by hybridization, mitochondrial DNA can introgress asymmetrically, from the outcompeted species into the invading species, over a large area. We explore this phenomenon using the two parapatric crested newt species, Triturus macedonicus and T. karelinii, distributed on the Balkan Peninsula in south-eastern Europe, as a model. Results We first delimit a ca. 54,000 km2 area in which T. macedonicus contains T. karelinii mitochondrial DNA. This introgression zone bisects the range of T. karelinii, cutting off a T. karelinii enclave. The high similarity of introgressed mitochondrial DNA haplotypes with those found in T. karelinii suggests a recent transfer across the species boundary. We then use ecological niche modeling to explore habitat suitability of the location of the present day introgression zone under current, mid-Holocene and Last Glacial Maximum conditions. This area was inhospitable during the Last Glacial Maximum for both species, but would have been habitable at the mid-Holocene. Since the mid-Holocene, habitat suitability generally increased for T. macedonicus, whereas it decreased for T. karelinii. Conclusion The presence of a T. karelinii enclave suggests that T. karelinii was the first to colonize the area where the present day introgression zone is positioned after the Last Glacial Maximum. Subsequently, we propose T. karelinii was outcompeted by T. macedonicus, which captured T. karelinii mitochondrial DNA via introgressive hybridization in the process. Ecological niche modeling suggests that this replacement was likely facilitated by a shift in climate since the mid-Holocene. We suggest that the northwestern part of the current introgression zone was probably never inhabited by T. karelinii itself, and that T. karelinii mitochondrial DNA spread there through T. macedonicus exclusively. Considering the spatial distribution of the

  12. Overexpression of mtDNA-associated AtWhy2 compromises mitochondrial function

    Directory of Open Access Journals (Sweden)

    Abou-Rached Charbel

    2008-04-01

    Full Text Available Abstract Background StWhy1, a member of the plant-specific Whirly single-stranded DNA-binding protein family, was first characterized as a transcription factor involved in the activation of the nuclear PR-10a gene following defense-related stress in potato. In Arabidopsis thaliana, Whirlies have recently been shown to be primarily localized in organelles. Two representatives of the family, AtWhy1 and AtWhy3 are imported into plastids while AtWhy2 localizes to mitochondria. Their function in organelles is currently unknown. Results To understand the role of mitochondrial Whirlies in higher plants, we produced A. thaliana lines with altered expression of the atwhy2 gene. Organellar DNA immunoprecipitation experiments demonstrated that AtWhy2 binds to mitochondrial DNA. Overexpression of atwhy2 in plants perturbs mitochondrial function by causing a diminution in transcript levels and mtDNA content which translates into a low activity level of respiratory chain complexes containing mtDNA-encoded subunits. This lowered activity of mitochondria yielded plants that were reduced in size and had distorted leaves that exhibited accelerated senescence. Overexpression of atwhy2 also led to early accumulation of senescence marker transcripts in mature leaves. Inactivation of the atwhy2 gene did not affect plant development and had no detectable effect on mitochondrial morphology, activity of respiratory chain complexes, transcription or the amount of mtDNA present. This lack of phenotype upon abrogation of atwhy2 expression suggests the presence of functional homologues of the Whirlies or the activation of compensating mechanisms in mitochondria. Conclusion AtWhy2 is associated with mtDNA and its overexpression results in the production of dysfunctional mitochondria. This report constitutes the first evidence of a function for the Whirlies in organelles. We propose that they could play a role in the regulation of the gene expression machinery of organelles.

  13. Ancient DNA and morphometric analysis reveal extinction and replacement of New Zealand's unique black swans.

    Science.gov (United States)

    Rawlence, Nicolas J; Kardamaki, Afroditi; Easton, Luke J; Tennyson, Alan J D; Scofield, R Paul; Waters, Jonathan M

    2017-07-26

    Prehistoric human impacts on megafaunal populations have dramatically reshaped ecosystems worldwide. However, the effects of human exploitation on smaller species, such as anatids (ducks, geese, and swans) are less clear. In this study we apply ancient DNA and osteological approaches to reassess the history of Australasia's iconic black swans ( Cygnus atratus ) including the palaeo-behaviour of prehistoric populations. Our study shows that at the time of human colonization, New Zealand housed a genetically, morphologically, and potentially ecologically distinct swan lineage ( C. sumnerensis , Poūwa), divergent from modern (Australian) C. atratus Morphological analyses indicate C. sumnerensis exhibited classic signs of the 'island rule' effect, being larger, and likely flight-reduced compared to C. atratus Our research reveals sudden extinction and replacement events within this anatid species complex, coinciding with recent human colonization of New Zealand. This research highlights the role of anthropogenic processes in rapidly reshaping island ecosystems and raises new questions for avian conservation, ecosystem re-wilding, and de-extinction. © 2017 The Author(s).

  14. Mitochondrial DNA T4216C and A4917G variations in multiple sclerosis

    DEFF Research Database (Denmark)

    Andalib, Sasan; Talebi, Mahnaz; Sakhinia, Ebrahim

    2015-01-01

    DNA gene and A4917G variation in the mtDNA NADH Dehydrogenase 2 (ND2) gene are associated with MS in an Iranian population. MATERIAL AND METHODS: Blood samples were collected from 100 patients with MS and 100 unrelated healthy controls, and DNA extraction was performed by salting-out. By means.......637). Logistic regression analysis revealed an odds ratio (OR) of 1.2 with 95% CI of 0.4-3.5. CONCLUSION: The present study revealed no association between MS and T4216C variation in the ND1 mtDNA gene and A4917G variation in the mtDNA ND2 gene in the Iranian population....... focuses on the neurogenetics of the complex pathogenesis of MS in relation to factors such as mitochondrial DNA (mtDNA) variations. T4216C and A4917G are common mitochondrial gene variations associated with MS. The present study tested whether mtDNA T4216C variation in the NADH Dehydrogenase 1 (ND1) mt...

  15. Mitochondrial DNA sequence variation in Finnish patients with matrilineal diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Soini Heidi K

    2012-07-01

    Full Text Available Abstract Background The genetic background of type 2 diabetes is complex involving contribution by both nuclear and mitochondrial genes. There is an excess of maternal inheritance in patients with type 2 diabetes and, furthermore, diabetes is a common symptom in patients with mutations in mitochondrial DNA (mtDNA. Polymorphisms in mtDNA have been reported to act as risk factors in several complex diseases. Findings We examined the nucleotide variation in complete mtDNA sequences of 64 Finnish patients with matrilineal diabetes. We used conformation sensitive gel electrophoresis and sequencing to detect sequence variation. We analysed the pathogenic potential of nonsynonymous variants detected in the sequences and examined the role of the m.16189 T>C variant. Controls consisted of non-diabetic subjects ascertained in the same population. The frequency of mtDNA haplogroup V was 3-fold higher in patients with diabetes. Patients harboured many nonsynonymous mtDNA substitutions that were predicted to be possibly or probably damaging. Furthermore, a novel m.13762 T>G in MTND5 leading to p.Ser476Ala and several rare mtDNA variants were found. Haplogroup H1b harbouring m.16189 T > C and m.3010 G > A was found to be more frequent in patients with diabetes than in controls. Conclusions Mildly deleterious nonsynonymous mtDNA variants and rare population-specific haplotypes constitute genetic risk factors for maternally inherited diabetes.

  16. Mitochondrial DNA Depletion in Respiratory Chain–Deficient Parkinson Disease Neurons

    Science.gov (United States)

    Rygiel, Karolina A.; Hepplewhite, Philippa D.; Morris, Christopher M.; Picard, Martin; Turnbull, Doug M.

    2016-01-01

    Objective To determine the extent of respiratory chain abnormalities and investigate the contribution of mtDNA to the loss of respiratory chain complexes (CI–IV) in the substantia nigra (SN) of idiopathic Parkinson disease (IPD) patients at the single‐neuron level. Methods Multiple‐label immunofluorescence was applied to postmortem sections of 10 IPD patients and 10 controls to quantify the abundance of CI–IV subunits (NDUFB8 or NDUFA13, SDHA, UQCRC2, and COXI) and mitochondrial transcription factors (TFAM and TFB2M) relative to mitochondrial mass (porin and GRP75) in dopaminergic neurons. To assess the involvement of mtDNA in respiratory chain deficiency in IPD, SN neurons, isolated with laser‐capture microdissection, were assayed for mtDNA deletions, copy number, and presence of transcription/replication‐associated 7S DNA employing a triplex real‐time polymerase chain reaction (PCR) assay. Results Whereas mitochondrial mass was unchanged in single SN neurons from IPD patients, we observed a significant reduction in the abundances of CI and II subunits. At the single‐cell level, CI and II deficiencies were correlated in patients. The CI deficiency concomitantly occurred with low abundances of the mtDNA transcription factors TFAM and TFB2M, which also initiate transcription‐primed mtDNA replication. Consistent with this, real‐time PCR analysis revealed fewer transcription/replication‐associated mtDNA molecules and an overall reduction in mtDNA copy number in patients. This effect was more pronounced in single IPD neurons with severe CI deficiency. Interpretation Respiratory chain dysfunction in IPD neurons not only involves CI, but also extends to CII. These deficiencies are possibly a consequence of the interplay between nDNA and mtDNA‐encoded factors mechanistically connected via TFAM. ANN NEUROL 2016;79:366–378 PMID:26605748

  17. Therapeutic Targeting of the Mitochondria Initiates Excessive Superoxide Production and Mitochondrial Depolarization Causing Decreased mtDNA Integrity.

    Science.gov (United States)

    Pokrzywinski, Kaytee L; Biel, Thomas G; Kryndushkin, Dmitry; Rao, V Ashutosh

    2016-01-01

    Mitochondrial dysregulation is closely associated with excessive reactive oxygen species (ROS) production. Altered redox homeostasis has been implicated in the onset of several diseases including cancer. Mitochondrial DNA (mtDNA) and proteins are particularly sensitive to ROS as they are in close proximity to the respiratory chain (RC). Mitoquinone (MitoQ), a mitochondria-targeted redox agent, selectively damages breast cancer cells possibly through damage induced via enhanced ROS production. However, the effects of MitoQ and other triphenylphosphonium (TPP+) conjugated agents on cancer mitochondrial homeostasis remain unknown. The primary objective of this study was to determine the impact of mitochondria-targeted agent [(MTAs) conjugated to TPP+: mitoTEMPOL, mitoquinone and mitochromanol-acetate] on mitochondrial physiology and mtDNA integrity in breast (MDA-MB-231) and lung (H23) cancer cells. The integrity of the mtDNA was assessed by quantifying the degree of mtDNA fragmentation and copy number, as well as by measuring mitochondrial proteins essential to mtDNA stability and maintenance (TFAM, SSBP1, TWINKLE, POLG and POLRMT). Mitochondrial status was evaluated by measuring superoxide production, mitochondrial membrane depolarization, oxygen consumption, extracellular acidification and mRNA or protein levels of the RC complexes along with TCA cycle activity. In this study, we demonstrated that all investigated MTAs impair mitochondrial health and decrease mtDNA integrity in MDA-MB-231 and H23 cells. However, differences in the degree of mitochondrial damage and mtDNA degradation suggest unique properties among each MTA that may be cell line, dose and time dependent. Collectively, our study indicates the potential for TPP+ conjugated molecules to impair breast and lung cancer cells by targeting mitochondrial homeostasis.

  18. Mechanism of Homologous Recombination and Implications for Aging-Related Deletions in Mitochondrial DNA

    Science.gov (United States)

    2013-01-01

    SUMMARY Homologous recombination is a universal process, conserved from bacteriophage to human, which is important for the repair of double-strand DNA breaks. Recombination in mitochondrial DNA (mtDNA) was documented more than 4 decades ago, but the underlying molecular mechanism has remained elusive. Recent studies have revealed the presence of a Rad52-type recombination system of bacteriophage origin in mitochondria, which operates by a single-strand annealing mechanism independent of the canonical RecA/Rad51-type recombinases. Increasing evidence supports the notion that, like in bacteriophages, mtDNA inheritance is a coordinated interplay between recombination, repair, and replication. These findings could have profound implications for understanding the mechanism of mtDNA inheritance and the generation of mtDNA deletions in aging cells. PMID:24006472

  19. High-Resolution Melting (HRM) of Hypervariable Mitochondrial DNA Regions for Forensic Science.

    Science.gov (United States)

    Dos Santos Rocha, Alípio; de Amorim, Isis Salviano Soares; Simão, Tatiana de Almeida; da Fonseca, Adenilson de Souza; Garrido, Rodrigo Grazinoli; Mencalha, Andre Luiz

    2018-03-01

    Forensic strategies commonly are proceeding by analysis of short tandem repeats (STRs); however, new additional strategies have been proposed for forensic science. Thus, this article standardized the high-resolution melting (HRM) of DNA for forensic analyzes. For HRM, mitochondrial DNA (mtDNA) from eight individuals were extracted from mucosa swabs by DNAzol reagent, samples were amplified by PCR and submitted to HRM analysis to identify differences in hypervariable (HV) regions I and II. To confirm HRM, all PCR products were DNA sequencing. The data suggest that is possible discriminate DNA from different samples by HRM curves. Also, uncommon dual-dissociation was identified in a single PCR product, increasing HRM analyzes by evaluation of melting peaks. Thus, HRM is accurate and useful to screening small differences in HVI and HVII regions from mtDNA and increase the efficiency of laboratory routines based on forensic genetics. © 2017 American Academy of Forensic Sciences.

  20. 4977-bp mitochondrial DNA deletion in infertile patients with varicocele.

    Science.gov (United States)

    Gashti, N G; Salehi, Z; Madani, A H; Dalivandan, S T

    2014-04-01

    Varicocele is the abnormal inflexion and distension of veins of the pampiniform plexus within spermatic cord and is one of the amendable causes of male infertility. It can increase reactive oxygen species (ROS) production in semen and cause oxidative stress. The purpose of this study was to analyse spermatozoa mtDNA 4977-bp deletion in infertile men with varicocele. To detect 4977-bp deletion in spermatozoa mtDNA, semen samples of 60 infertile patients with clinical varicocele and 90 normal men from northern Iran were prepared. After extraction of spermatozoa total DNA, Gap polymerase chain reaction (Gap PCR) was performed. 4977-bp deletion was observed in 81.66% of patients with varicocele, while approximately 15.55% of controls had this deletion. As spermatozoa from patients with varicocele had a high frequency of occurrence of 4977-bp deletion in mtDNA [OR = 24.18, 95% confidence interval (CI) = 10.15-57.57, P deletion in spermatozoa and cause infertility in north Iranian men. However, to determine the relation between sperm mtDNA 4977-bp deletion and varicocele-induced infertility, larger population-based studies are needed. It is concluded that there is an association between sperm mtDNA 4977-bp deletion and varicocele-induced infertility in the population studied. © 2013 Blackwell Verlag GmbH.

  1. Double-stranded DNA-dependent ATPase Irc3p is directly involved in mitochondrial genome maintenance.

    Science.gov (United States)

    Sedman, Tiina; Gaidutšik, Ilja; Villemson, Karin; Hou, YingJian; Sedman, Juhan

    2014-12-01

    Nucleic acid-dependent ATPases are involved in nearly all aspects of DNA and RNA metabolism. Previous studies have described a number of mitochondrial helicases. However, double-stranded DNA-dependent ATPases, including translocases or enzymes remodeling DNA-protein complexes, have not been identified in mitochondria of the yeast Saccharomyces cerevisae. Here, we demonstrate that Irc3p is a mitochondrial double-stranded DNA-dependent ATPase of the Superfamily II. In contrast to the other mitochondrial Superfamily II enzymes Mss116p, Suv3p and Mrh4p, which are RNA helicases, Irc3p has a direct role in mitochondrial DNA (mtDNA) maintenance. Specific Irc3p-dependent mtDNA metabolic intermediates can be detected, including high levels of double-stranded DNA breaks that accumulate in irc3Δ mutants. irc3Δ-related topology changes in rho- mtDNA can be reversed by the deletion of mitochondrial RNA polymerase RPO41, suggesting that Irc3p counterbalances adverse effects of transcription on mitochondrial genome stability. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  2. Evaluating the role of mitochondrial DNA variation to the genetic predisposition to radiation-induced toxicity

    International Nuclear Information System (INIS)

    Fachal, Laura; Mosquera-Miguel, Ana; Gómez-Caamaño, Antonio; Sánchez-García, Manuel; Calvo, Patricia; Lobato-Busto, Ramón; Salas, Antonio; Vega, Ana

    2014-01-01

    Background and purpose: Mitochondrial DNA common variants have been reported to be associated with the development of radiation-induced toxicity. Using a large cohort of patients, we aimed to validate these findings by investigating the potential role of common European mitochondrial DNA SNPs (mtSNPs) to the development of radio-toxicity. Material and methods: Overall acute and late toxicity data were assessed in a cohort of 606 prostate cancer patients by means of Standardized Total Average Toxicity (STAT) score. We carried out association tests between radiation toxicity and a selection of 15 mtSNPs (and the haplogroups defined by them). Results: Statistically significant association between mtSNPs and haplogroups with toxicity could not be validated in our Spanish cohort. Conclusions: The present study suggests that the mtDNA common variants analyzed are not associated with clinically relevant increases in risk of overall radiation-induced toxicity in prostate cancer patients

  3. Prevalence of migraine in persons with the 3243A>G mutation in mitochondrial DNA

    DEFF Research Database (Denmark)

    Guo, S.; Esserlind, A-L; Andersson, Z

    2016-01-01

    % vs. 6%; P persons with the mDNA 3243A>G mutation was found. This finding suggests a clinical association between a monogenetically inherited disorder......BACKGROUND AND PURPOSE: Over the last three decades mitochondrial dysfunction has been postulated to be a potential mechanism in migraine pathogenesis. The lifetime prevalence of migraine in persons carrying the 3243A>G mutation in mitochondrial DNA was investigated. METHODS: In this cross......-sectional study, 57 mDNA 3243A>G mutation carriers between May 2012 and October 2014 were included. As a control group, a population-based cohort from our epidemiological studies on migraine in Danes was used. History of headache and migraine was obtained by telephone interview, based on a validated semi...

  4. Mitochondrial DNA deletion mutations in adult mouse cardiac side population cells

    International Nuclear Information System (INIS)

    Lushaj, Entela B.; Lozonschi, Lucian; Barnes, Maria; Anstadt, Emily; Kohmoto, Takushi

    2012-01-01

    We investigated the presence and potential role of mitochondrial DNA (mtDNA) deletion mutations in adult cardiac stem cells. Cardiac side population (SP) cells were isolated from 12-week-old mice. Standard polymerase chain reaction (PCR) was used to screen for the presence of mtDNA deletion mutations in (a) freshly isolated SP cells and (b) SP cells cultured to passage 10. When present, the abundance of mtDNA deletion mutation was analyzed in single cell colonies. The effect of different levels of deletion mutations on SP cell growth and differentiation was determined. MtDNA deletion mutations were found in both freshly isolated and cultured cells from 12-week-old mice. While there was no significant difference in the number of single cell colonies with mtDNA deletion mutations from any of the groups mentioned above, the abundance of mtDNA deletion mutations was significantly higher in the cultured cells, as determined by quantitative PCR. Within a single clonal cell population, the detectable mtDNA deletion mutations were the same in all cells and unique when compared to deletions of other colonies. We also found that cells harboring high levels of mtDNA deletion mutations (i.e. where deleted mtDNA comprised more than 60% of total mtDNA) had slower proliferation rates and decreased differentiation capacities. Screening cultured adult stem cells for mtDNA deletion mutations as a routine assessment will benefit the biomedical application of adult stem cells.

  5. DNA typing of ancient parasite eggs from environmental samples identifies human and animal worm infections in Viking-age settlement.

    Science.gov (United States)

    Søe, Martin Jensen; Nejsum, Peter; Fredensborg, Brian Lund; Kapel, Christian Moliin Outzen

    2015-02-01

    Ancient parasite eggs were recovered from environmental samples collected at a Viking-age settlement in Viborg, Denmark, dated 1018-1030 A.D. Morphological examination identified Ascaris sp., Trichuris sp., and Fasciola sp. eggs, but size and shape did not allow species identification. By carefully selecting genetic markers, PCR amplification and sequencing of ancient DNA (aDNA) isolates resulted in identification of: the human whipworm, Trichuris trichiura , using SSUrRNA sequence homology; Ascaris sp. with 100% homology to cox1 haplotype 07; and Fasciola hepatica using ITS1 sequence homology. The identification of T. trichiura eggs indicates that human fecal material is present and, hence, that the Ascaris sp. haplotype 07 was most likely a human variant in Viking-age Denmark. The location of the F. hepatica finding suggests that sheep or cattle are the most likely hosts. Further, we sequenced the Ascaris sp. 18S rRNA gene in recent isolates from humans and pigs of global distribution and show that this is not a suited marker for species-specific identification. Finally, we discuss ancient parasitism in Denmark and the implementation of aDNA analysis methods in paleoparasitological studies. We argue that when employing species-specific identification, soil samples offer excellent opportunities for studies of human parasite infections and of human and animal interactions of the past.

  6. The Geographic Origins of Ethnic Groups in the Indian Subcontinent: Exploring Ancient Footprints with Y-DNA Haplogroups

    Directory of Open Access Journals (Sweden)

    David G. Mahal

    2018-01-01

    Full Text Available Several studies have evaluated the movements of large populations to the Indian subcontinent; however, the ancient geographic origins of smaller ethnic communities are not clear. Although historians have attempted to identify the origins of some ethnic groups, the evidence is typically anecdotal and based upon what others have written before. In this study, recent developments in DNA science were assessed to provide a contemporary perspective by analyzing the Y chromosome haplogroups of some key ethnic groups and tracing their ancient geographical origins from genetic markers on the Y-DNA haplogroup tree. A total of 2,504 Y-DNA haplotypes, representing 50 different ethnic groups in the Indian subcontinent, were analyzed. The results identified 14 different haplogroups with 14 geographic origins for these people. Moreover, every ethnic group had representation in more than one haplogroup, indicating multiple geographic origins for these communities. The results also showed that despite their varied languages and cultural differences, most ethnic groups shared some common ancestors because of admixture in the past. These findings provide new insights into the ancient geographic origins of ethnic groups in the Indian subcontinent. With about 2,000 other ethnic groups and tribes in the region, it is expected that more scientific discoveries will follow, providing insights into how, from where, and when the ancestors of these people arrived in the subcontinent to create so many different communities.

  7. Identification of Forensic Samples via Mitochondrial DNA in the Undergraduate Biochemistry Laboratory

    Science.gov (United States)

    Millard, Julie T.; Pilon, André M.

    2003-04-01

    A recent forensic approach for identification of unknown biological samples is mitochondrial DNA (mtDNA) sequencing. We describe a laboratory exercise suitable for an undergraduate biochemistry course in which the polymerase chain reaction is used to amplify a 440 base pair hypervariable region of human mtDNA from a variety of "crime scene" samples (e.g., teeth, hair, nails, cigarettes, envelope flaps, toothbrushes, and chewing gum). Amplification is verified via agarose gel electrophoresis and then samples are subjected to cycle sequencing. Sequence alignments are made via the program CLUSTAL W, allowing students to compare samples and solve the "crime."

  8. Non-invasive ancient DNA protocol for fluid-preserved specimens and phylogenetic systematics of the genus Orestias (Teleostei: Cyprinodontidae).

    Science.gov (United States)

    Garrigos, Yareli Esquer; Hugueny, Bernard; Koerner, Kellie; Ibañez, Carla; Bonillo, Celine; Pruvost, Patrice; Causse, Romain; Cruaud, Corinne; Gaubert, Philippe

    2013-01-01

    Specimens stored in museum collections represent a crucial source of morphological and genetic information, notably for taxonomically problematic groups and extinct taxa. Although fluid-preserved specimens of groups such as teleosts may constitute an almost infinite source of DNA, few ancient DNA protocols have been applied to such material. In this study, we describe a non-invasive Guanidine-based (GuSCN) ancient DNA extraction protocol adapted to fluid-preserved specimens that we use to re-assess the systematics of the genus Orestias (Cyprinodontidae: Teleostei). The latter regroups pupfishes endemic to the inter-Andean basin that have been considered as a 'species flock', and for which the morphology-based taxonomic delimitations have been hotly debated. We extracted DNA from the type specimens of Orestias kept at the Muséum National d'Histoire Naturelle of Paris, France, including the extinct species O. cuvieri. We then built the first molecular (control region [CR] and rhodopsin [RH]) phylogeny including historical and recently collected representatives of all the Orestias complexes as recognized by Parenti (1984a): agassizii, cuvieri, gilsoni and mulleri. Our ancient DNA extraction protocol was validated after PCR amplification through an approach based on fragment-by-fragment chimera detection. After optimization, we were able to amplify Titicaca. We could not recover the reciprocal monophyly of any of the 15 species or morphotypes that were considered in our analyses, possibly due to incomplete lineage sorting and/or hybridization events. As a consequence, our results starkly question the delineation of a series of diagnostic characters listed in the literature for Orestias. Although not included in our phylogenetic analysis, the syntype of O. jussiei could not be assigned to the agassizii complex as newly defined. The CR sequence of the extinct O. cuvieri was recovered within the cuvieri clade (same haplotype as one representative of O. pentlandii), so

  9. Norgal: extraction and de novo assembly of mitochondrial DNA from whole-genome sequencing data.

    Science.gov (United States)

    Al-Nakeeb, Kosai; Petersen, Thomas Nordahl; Sicheritz-Pontén, Thomas

    2017-11-21

    Whole-genome sequencing (WGS) projects provide short read nucleotide sequences from nuclear and possibly organelle DNA depending on the source of origin. Mitochondrial DNA is present in animals and fungi, while plants contain DNA from both mitochondria and chloroplasts. Current techniques for separating organelle reads from nuclear reads in WGS data require full reference or partial seed sequences for assembling. Norgal (de Novo ORGAneLle extractor) avoids this requirement by identifying a high frequency subset of k-mers that are predominantly of mitochondrial origin and performing a de novo assembly on a subset of reads that contains these k-mers. The method was applied to WGS data from a panda, brown algae seaweed, butterfly and filamentous fungus. We were able to extract full circular mitochondrial genomes and obtained sequence identities to the reference sequences in the range from 98.5 to 99.5%. We also assembled the chloroplasts of grape vines and cucumbers using Norgal together with seed-based de novo assemblers. Norgal is a pipeline that can extract and assemble full or partial mitochondrial and chloroplast genomes from WGS short reads without prior knowledge. The program is available at: https://bitbucket.org/kosaidtu/norgal .

  10. Mitochondrial DNA deletion in a patient with combined features of Leigh and Pearson syndromes

    Energy Technology Data Exchange (ETDEWEB)

    Blok, R.B.; Thorburn, D.R.; Danks, D.M. [Royal Children`s Hospital, Melbourne (Australia)] [and others

    1994-09-01

    We describe a heteroplasmic 4237 bp mitochondrial DNA (mtDNA) deletion in an 11 year old girl who has suffered from progressive illness since birth. She has some features of Leigh syndrome (global developmental delay with regression, brainstem dysfunction and lactic acidosis), together with other features suggestive of Pearson syndrome (history of pancytopenia and failure to thrive). The deletion was present at a level greater than 50% in skeletal muscle, but barely detectable in skin fibroblasts following Southern blot analysis, and only observed in blood following PCR analysis. The deletion spanned nt 9498 to nt 13734, and was flanked by a 12 bp direct repeat. Genes for cytochrome c oxidase subunit III, NADH dehydrogenase subunits 3, 4L, 4 and 5, and tRNAs for glycine, arginine, histidine, serine({sup AGY}) and leucine({sup CUN}) were deleted. Southern blotting also revealed an altered Apa I restriction site which was shown by sequence analysis to be caused by G{r_arrow}A nucleotide substitution at nt 1462 in the 12S rRNA gene. This was presumed to be a polymorphism. No abnormalities of mitochondrial ultrastructure, distribution or of respiratory chain enzyme complexes I-IV in skeletal muscle were observed. Mitochondrial disorders with clinical features overlapping more than one syndrome have been reported previously. This case further demonstrates the difficulty in correlating observed clinical features with a specific mitochondrial DNA mutation.

  11. Full mitochondrial genome sequences of two endemic Philippine hornbill species (Aves: Bucerotidae) provide evidence for pervasive mitochondrial DNA recombination.

    Science.gov (United States)

    Sammler, Svenja; Bleidorn, Christoph; Tiedemann, Ralph

    2011-01-14

    Although nowaday it is broadly accepted that mitochondrial DNA (mtDNA) may undergo recombination, the frequency of such recombination remains controversial. Its estimation is not straightforward, as recombination under homoplasmy (i.e., among identical mt genomes) is likely to be overlooked. In species with tandem duplications of large mtDNA fragments the detection of recombination can be facilitated, as it can lead to gene conversion among duplicates. Although the mechanisms for concerted evolution in mtDNA are not fully understood yet, recombination rates have been estimated from "one per speciation event" down to 850 years or even "during every replication cycle". Here we present the first complete mt genome of the avian family Bucerotidae, i.e., that of two Philippine hornbills, Aceros waldeni and Penelopides panini. The mt genomes are characterized by a tandemly duplicated region encompassing part of cytochrome b, 3 tRNAs, NADH6, and the control region. The duplicated fragments are identical to each other except for a short section in domain I and for the length of repeat motifs in domain III of the control region. Due to the heteroplasmy with regard to the number of these repeat motifs, there is some size variation in both genomes; with around 21,657 bp (A. waldeni) and 22,737 bp (P. panini), they significantly exceed the hitherto longest known avian mt genomes, that of the albatrosses. We discovered concerted evolution between the duplicated fragments within individuals. The existence of differences between individuals in coding genes as well as in the control region, which are maintained between duplicates, indicates that recombination apparently occurs frequently, i.e., in every generation. The homogenised duplicates are interspersed by a short fragment which shows no sign of recombination. We hypothesize that this region corresponds to the so-called Replication Fork Barrier (RFB), which has been described from the chicken mitochondrial genome. As this RFB

  12. Full mitochondrial genome sequences of two endemic Philippine hornbill species (Aves: Bucerotidae provide evidence for pervasive mitochondrial DNA recombination

    Directory of Open Access Journals (Sweden)

    Bleidorn Christoph

    2011-01-01

    Full Text Available Abstract Background Although nowaday it is broadly accepted that mitochondrial DNA (mtDNA may undergo recombination, the frequency of such recombination remains controversial. Its estimation is not straightforward, as recombination under homoplasmy (i.e., among identical mt genomes is likely to be overlooked. In species with tandem duplications of large mtDNA fragments the detection of recombination can be facilitated, as it can lead to gene conversion among duplicates. Although the mechanisms for concerted evolution in mtDNA are not fully understood yet, recombination rates have been estimated from "one per speciation event" down to 850 years or even "during every replication cycle". Results Here we present the first complete mt genome of the avian family Bucerotidae, i.e., that of two Philippine hornbills, Aceros waldeni and Penelopides panini. The mt genomes are characterized by a tandemly duplicated region encompassing part of cytochrome b, 3 tRNAs, NADH6, and the control region. The duplicated fragments are identical to each other except for a short section in domain I and for the length of repeat motifs in domain III of the control region. Due to the heteroplasmy with regard to the number of these repeat motifs, there is some size variation in both genomes; with around 21,657 bp (A. waldeni and 22,737 bp (P. panini, they significantly exceed the hitherto longest known avian mt genomes, that of the albatrosses. We discovered concerted evolution between the duplicated fragments within individuals. The existence of differences between individuals in coding genes as well as in the control region, which are maintained between duplicates, indicates that recombination apparently occurs frequently, i.e., in every generation. Conclusions The homogenised duplicates are interspersed by a short fragment which shows no sign of recombination. We hypothesize that this region corresponds to the so-called Replication Fork Barrier (RFB, which has been

  13. Subspecific Status of the Korean Tiger Inferred by Ancient DNA Analysis

    Directory of Open Access Journals (Sweden)

    Mu-Yeong Lee

    2012-01-01

    Full Text Available The tiger population that once inhabited the Korean peninsula was initially considered a unique subspecies (Panthera tigris coreensis, distinct from the Amur tiger of the Russian Far East (P. t. altaica. However, in the following decades, the population of P. t. coreensis was classified as P. t. altaica and hence forth the two populations have been considered the same subspecies. From an ecological point of view, the classification of the Korean tiger population as P. t. altaica is a plausible conclusion. Historically, there were no major dispersal barriers between the Korean peninsula and the habitat of Amur tigers in Far Eastern Russia and northeastern China that might prevent gene flow, especially for a large carnivore with long-distance dispersal abilities. However, there has yet to be a genetic study to confirm the subspecific status of the Korean tiger. Bone samples from four tigers originally caught in the Korean peninsula were collected from two museums in Japan and the United States. Eight mitochondrial gene fragments were sequenced and compared to previously published tiger subspecies’ mtDNA sequences to assess the phylogenetic relationship of the Korean tiger. Three individuals shared an identical haplotype with the Amur tigers. One specimen grouped with Malayan tigers, perhaps due to misidentification or mislabeling of the sample. Our results support the conclusion that the Korean tiger should be classified as P. t. altaica, which has important implications for the conservation and reintroduction of Korean tigers.

  14. Distribution patterns of postmortem damage in human mitochondrial DNA

    DEFF Research Database (Denmark)

    Gilbert, M Thomas P; Willerslev, Eske; Hansen, Anders J

    2002-01-01

    1 (HVR1) and cytochrome oxidase subunit III genes. A comparison of damaged sites within and between the regions reveals that damage hotspots exist and that, in the HVR1, these correlate with sites known to have high in vivo mutation rates. Conversely, HVR1 subregions with known structural function......, such as MT5, have lower in vivo mutation rates and lower postmortem-damage rates. The postmortem data also identify a possible functional subregion of the HVR1, termed "low-diversity 1," through the lack of sequence damage. The amount of postmortem damage observed in mitochondrial coding regions...... was significantly lower than in the HVR1, and, although hotspots were noted, these did not correlate with codon position. Finally, a simple method for the identification of incorrect archaeological haplogroup designations is introduced, on the basis of the observed spectrum of postmortem damage....

  15. Meat species identification and Halal authentication analysis using mitochondrial DNA.

    Science.gov (United States)

    Murugaiah, Chandrika; Noor, Zainon Mohd; Mastakim, Maimunah; Bilung, Lesley Maurice; Selamat, Jinap; Radu, Son

    2009-09-01

    A method utilizing PCR-restriction fragment length polymorphism (RFLP) in the mitochondrial genes was developed for beef (Bos taurus), pork (Sus scrofa), buffalo (Bubalus bubali), quail (Coturnix coturnix), chicken (Gallus gallus), goat (Capra hircus), rabbit (Oryctolagus cuniculus) species identification and Halal authentication. PCR products of 359-bp were successfully obtained from the cyt b gene of these six meats. AluI, BsaJI, RsaI, MseI, and BstUI enzymes were identified as potential restriction endonucleases to differentiate the meats. The genetic differences within the cyt b gene among the meat were successfully confirmed by PCR-RFLP. A reliable typing scheme of species which revealed the genetic differences among the species was developed.

  16. Inheritance of mitochondrial DNA in serially recloned pigs by somatic cell nuclear transfer (SCNT)

    Energy Technology Data Exchange (ETDEWEB)

    Do, Minhwa; Jang, Won-Gu; Hwang, Jeong Hee; Jang, Hoon; Kim, Eun-Jung; Jeong, Eun-Jeong [Regenerative Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305 806 (Korea, Republic of); Shim, Hosup [Department of Physiology, Dankook University School of Medicine, Cheonan 330 714 (Korea, Republic of); Hwang, Sung Soo; Oh, Keon Bong; Byun, Sung June [Animal Biotechnology Division, National Institute of Animal Science, Rural Development Administration, Suwon (Korea, Republic of); Kim, Jin-Hoi [Department of Animal Biotechnology, Konkuk University, Seoul 143 701 (Korea, Republic of); Lee, Jeong Woong, E-mail: jwlee@kribb.re.kr [Regenerative Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305 806 (Korea, Republic of)

    2012-08-10

    Highlights: Black-Right-Pointing-Pointer We success serial SCNT through the third generation using pig fibroblasts. Black-Right-Pointing-Pointer Donor-specific mtDNA in the recloned pigs was detected. Black-Right-Pointing-Pointer SCNT affect mtDNA mounts. -- Abstract: Somatic cell nuclear transfer (SCNT) has been established for the transmission of specific nuclear DNA. However, the fate of donor mitochondrial DNA (mtDNA) remains unclear. Here, we examined the fate of donor mtDNA in recloned pigs through third generations. Fibroblasts of recloned pigs were obtained from offspring of each generation produced by fusion of cultured fibroblasts from a Minnesota miniature pig (MMP) into enucleated oocytes of a Landrace pig. The D-loop regions from the mtDNA of donor and recipient differ at nucleotide sequence positions 16050 (A{yields}T), 16062 (T{yields}C), and 16135 (G{yields}A). In order to determine the fate of donor mtDNA in recloned pigs, we analyzed the D-loop region of the donor's mtDNA by allele-specific PCR (AS-PCR) and real-time PCR. Donor mtDNA was successfully detected in all recloned offspring (F1, F2, and F3). These results indicate that heteroplasmy that originate from donor and recipient mtDNA is maintained in recloned pigs, resulting from SCNT, unlike natural reproduction.

  17. Reduced mitochondrial DNA content associates with poor prognosis of prostate cancer in African American men.

    Directory of Open Access Journals (Sweden)

    Shahriar Koochekpour

    Full Text Available Reduction or depletion of mitochondrial DNA (mtDNA has been associated with cancer progression. Although imbalanced mtDNA content is known to occur in prostate cancer, differences in mtDNA content between African American (AA and Caucasian American (CA men are not defined. We provide the first evidence that tumors in AA men possess reduced level of mtDNA compared to CA men. The median tumor mtDNA content was reduced in AA men. mtDNA content was also reduced in normal prostate tissues of AA men compared to CA men, suggesting a possible predisposition to cancer in AA men. mtDNA content was also reduced in benign prostatic hyperplasia (BPH tissue from AA men. Tumor and BPH tissues from patients ≥ 60 years of age possess reduced mtDNA content compared to patients 7 compared to ≤ 7, whereas reduced mtDNA content was observed in tumors of Gleason grade >7 compared to ≤ 7. Together, our data suggest that AA men possess lower mtDNA levels in normal and tumor tissues compared to CA men, which could contribute to higher risk and more aggressive prostate cancer in AA men.

  18. Reduced mitochondrial DNA content associates with poor prognosis of prostate cancer in African American men.

    Science.gov (United States)

    Koochekpour, Shahriar; Marlowe, Timothy; Singh, Keshav K; Attwood, Kristopher; Chandra, Dhyan

    2013-01-01

    Reduction or depletion of mitochondrial DNA (mtDNA) has been associated with cancer progression. Although imbalanced mtDNA content is known to occur in prostate cancer, differences in mtDNA content between African American (AA) and Caucasian American (CA) men are not defined. We provide the first evidence that tumors in AA men possess reduced level of mtDNA compared to CA men. The median tumor mtDNA content was reduced in AA men. mtDNA content was also reduced in normal prostate tissues of AA men compared to CA men, suggesting a possible predisposition to cancer in AA men. mtDNA content was also reduced in benign prostatic hyperplasia (BPH) tissue from AA men. Tumor and BPH tissues from patients ≥ 60 years of age possess reduced mtDNA content compared to patients 7 compared to ≤ 7, whereas reduced mtDNA content was observed in tumors of Gleason grade >7 compared to ≤ 7. Together, our data suggest that AA men possess lower mtDNA levels in normal and tumor tissues compared to CA men, which could contribute to higher risk and more aggressive prostate cancer in AA men.

  19. Accurate measurement of mitochondrial DNA deletion level and copy number differences in human skeletal muscle.

    Directory of Open Access Journals (Sweden)

    John P Grady

    Full Text Available Accurate and reliable quantification of the abundance of mitochondrial DNA (mtDNA molecules, both wild-type and those harbouring pathogenic mutations, is important not only for understanding the progression of mtDNA disease but also for evaluating novel therapeutic approaches. A clear understanding of the sensitivity of mtDNA measurement assays under different experimental conditions is therefore critical, however it is routinely lacking for most published mtDNA quantification assays. Here, we comprehensively assess the variability of two quantitative Taqman real-time PCR assays, a widely-applied MT-ND1/MT-ND4 multiplex mtDNA deletion assay and a recently developed MT-ND1/B2M singleplex mtDNA copy number assay, across a range of DNA concentrations and mtDNA deletion/copy number levels. Uniquely, we provide a specific guide detailing necessary numbers of sample and real-time PCR plate replicates for accurately and consistently determining a given difference in mtDNA deletion levels and copy number in homogenate skeletal muscle DNA.

  20. Accumulation of linear mitochondrial DNA fragments in the nucleus shortens the chronological life span of yeast.

    Science.gov (United States)

    Cheng, Xin; Ivessa, Andreas S

    2012-10-01

    Translocation of mitochondrial DNA (mtDNA) fragments to the nucleus and insertion of those fragments into nuclear DNA has been observed in several organisms ranging from yeast to plants and mammals. Disruption of specific nuclear genes by de novo insertions of mtDNA fragments has even been linked to the initiation of several human diseases. Recently, we demonstrated that baker's yeast strains with high rates of mtDNA fragments migrating to the nucleus (yme1-1 mutant) exhibit short chronological life spans (CLS). The yeast CLS is determined by the survival of non-dividing cell populations. Here, we show that lack of the non-homologous-end-joining enzyme DNA ligase IV (DNL4) can rescue the short CLS of the yme1-1 mutant. In fission yeast, DNA ligase IV has been shown to be required for the capture of mtDNA fragments during the repair of double-stranded DNA breaks in nuclear DNA. In further analyses using pulse field gel and 2D gel electrophoresis we demonstrate that linear mtDNA fragments with likely nuclear localization accumulate in the yme1-1 mutant. The accumulation of the linear mtDNA fragments in the yme1-1 mutant is suppressed when Dnl4 is absent. We propose that the linear nuclear mtDNA fragments accelerate the aging process in the yme1-1 mutant cells by possibly affecting nuclear processes including DNA replication, recombination, and repair as well as transcription of nuclear genes. We speculate further that Dnl4 protein has besides its function as a ligase also a role in DNA protection. Dnl4 protein may stabilize the linear mtDNA fragments in the nucleus by binding to their physical ends. In the absence of Dnl4 protein the linear fragments are therefore unprotected and possibly degraded by nuclear nucleases. Copyright © 2012 Elsevier GmbH. All rights reserved.

  1. Decreased mitochondrial DNA content in blood samples of patients with stage I breast cancer

    International Nuclear Information System (INIS)

    Xia, Peng; An, Han-Xiang; Dang, Cheng-Xue; Radpour, Ramin; Kohler, Corina; Fokas, Emmanouil; Engenhart-Cabillic, Rita; Holzgreve, Wolfgang; Zhong, Xiao Yan

    2009-01-01

    Alterations of mitochondrial DNA (mtDNA) have been implicated in carcinogenesis. We developed an accurate multiplex quantitative real-time PCR for synchronized determination of mtDNA and nuclear DNA (nDNA). We sought to investigate whether mtDNA content in the peripheral blood of breast cancer patients is associated with clinical and pathological parameters. Peripheral blood samples were collected from 60 patients with breast cancer and 51 age-matched healthy individuals as control. DNA was extracted from peripheral blood for the quantification of mtDNA and nDNA, using a one-step multiplex real-time PCR. A FAM labeled MGB probe and primers were used to amplify the mtDNA sequence of the ATP 8 gene, and a VIC labeled MGB probe and primers were employed to amplify the glyceraldehyde-3-phosphate-dehydrogenase gene. mtDNA content was correlated with tumor stage, menstruation status, and age of patients as well as lymph node status and the expression of estrogen receptor (ER), progesterone receptor (PR) and Her-2/neu protein. The content of mtDNA in stage I breast cancer patients was significantly lower than in other stages (overall P = 0.023). Reduced mtDNA was found often in post menopausal cancer group (P = 0.024). No difference in mtDNA content, in regards to age (p = 0.564), lymph node involvement (p = 0.673), ER (p = 0.877), PR (p = 0.763), and Her-2/neu expression (p = 0.335), was observed. Early detection of breast cancer has proved difficult and current detection methods are inadequate. In the present study, decreased mtDNA content in the peripheral blood of patients with breast cancer was strongly associated with stage I. The use of mtDNA may have diagnostic value and further studies are required to validate it as a potential biomarker for early detection of breast cancer

  2. TDP1 repairs nuclear and mitochondrial DNA damage induced by chain-terminating anticancer and antiviral nucleoside analogs

    Science.gov (United States)

    Huang, Shar-yin N.; Murai, Junko; Dalla Rosa, Ilaria; Dexheimer, Thomas S.; Naumova, Alena; Gmeiner, William H.; Pommier, Yves

    2013-01-01

    Chain-terminating nucleoside analogs (CTNAs) that cause stalling or premature termination of DNA replication forks are widely used as anticancer and antiviral drugs. However, it is not well understood how cells repair the DNA damage induced by these drugs. Here, we reveal the importance of tyrosyl–DNA phosphodiesterase 1 (TDP1) in the repair of nuclear and mitochondrial DNA damage induced by CTNAs. On investigating the effects of four CTNAs—acyclovir (ACV), cytarabine (Ara-C), zidovudine (AZT) and zalcitabine (ddC)—we show that TDP1 is capable of removing the covalently linked corresponding CTNAs from DNA 3′-ends. We also show that Tdp1−/− cells are hypersensitive and accumulate more DNA damage when treated with ACV and Ara-C, implicating TDP1 in repairing CTNA-induced DNA damage. As AZT and ddC are known to cause mitochondrial dysfunction, we examined whether TDP1 repairs the mitochondrial DNA damage they induced. We find that AZT and ddC treatment leads to greater depletion of mitochondrial DNA in Tdp1−/− cells. Thus, TDP1 seems to be critical for repairing nuclear and mitochondrial DNA damage caused by CTNAs. PMID:23775789

  3. Characterization of Fasciola spp. in Myanmar on the basis of spermatogenesis status and nuclear and mitochondrial DNA markers.

    Science.gov (United States)

    Ichikawa, Madoka; Bawn, Saw; Maw, Ni Ni; Htun, Lat Lat; Thein, Myint; Gyi, Aung; Sunn, Kyaw; Katakura, Ken; Itagaki, Tadashi

    2011-12-01

    Fasciola spp. in Myanmar were characterized on the basis of spermatogenesis status and DNA markers of nuclear internal transcribed spacer 1 (ITS1) and mitochondrial NADH dehydrogenase subunit 1 (nad1). We collected 88 adult flukes from Yangon, Lashio, and Myitkyina. Spermatogenesis status was analyzed by the presence of sperm in the seminal vesicles, and 8 aspermic and 80 spermic flukes were detected. The flukes were identified on the basis of spermatogenesis status and ITS1 types which were analyzed by a PCR-RFLP method, and 80 spermic flukes were identified as F. gigantica. A very low detection rate of aspermic Fasciola sp. indicated that they are not established in Myanmar. In phylogenetic analyses, the 7 aspermic Fasciola sp. from Myitkyina displayed a haplotype in nad1 sequence, which was identical to that of aspermic Fasciola sp. from other Asian countries including China. Therefore, they were probably introduced from China through an infected domestic ruminant. On the other hand, 17 nad1 haplotypes detected in F. gigantica belonged to 2 clades unique to Myanmar, each with a distinct founder haplotype in a network analysis. This indicated a unique history of F. gigantica introduction into Myanmar involving ancient artificial movements of domestic ruminants. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  4. A novel mutation in the mitochondrial DNA cytochrome b gene (MTCYB) in a patient with mitochondrial encephalomyopathy, lactic acidosis, and strokelike episodes syndrome.

    Science.gov (United States)

    Emmanuele, Valentina; Sotiriou, Evangelia; Rios, Purificación Gutierrez; Ganesh, Jaya; Ichord, Rebecca; Foley, A Reghan; Akman, H Orhan; Dimauro, Salvatore

    2013-02-01

    Mutations in the mitochondrial DNA cytochrome b gene (MTCYB) have been commonly associated with isolated mitochondrial myopathy and exercise intolerance, rarely with multisystem disorders, and only once with a parkinsonism/mitochondrial encephalomyopathy, lactic acidosis, and strokelike episodes (MELAS) overlap syndrome. Here, we describe a novel mutation (m.14864 T>C) in MTCYB in a 15-year-old girl with a clinical history of migraines, epilepsy, sensorimotor neuropathy, and strokelike episodes, a clinical picture reminiscent of MELAS.  The mutation, which changes a highly conserved cysteine to arginine at amino acid position 40 of cytochrome b, was heteroplasmic in muscle, blood, fibroblasts, and urinary sediment from the patient but absent in accessible tissues from her asymptomatic mother. This case demonstrates that MTCYB must be included in the already long list of mitochondrial DNA genes that have been associated with the MELAS phenotype.

  5. Forensic analysis of mitochondrial DNA hypervariable region HVII ...

    African Journals Online (AJOL)

    aghomotsegin

    2015-02-04

    Feb 4, 2015 ... as even species thought to be closely related may in time accumulate ... have attracted the interest of population geneticists (Al-. Zahery et al. ... portion of DNA was amplified in two primers: the first one is HVIII-F. (438-459) ...

  6. Mitochondrial DNA genetic variations among four horse populations in Egypt

    Directory of Open Access Journals (Sweden)

    Othman E. Othman

    2017-12-01

    It is concluded that sequence analysis of mtDNA control region is still the most informative tool for the identification of genetic biodiversity and phylogeny of different horse breeds and populations. The horse populations reared in Egypt possess low genetic diversity and all of them are belonged to Equus caballus breed.

  7. Mitochondrial DNA sequencing of cat hair: an informative forensic tool.

    Science.gov (United States)

    Tarditi, Christy R; Grahn, Robert A; Evans, Jeffrey J; Kurushima, Jennifer D; Lyons, Leslie A

    2011-01-01

    Approximately 81.7 million cats are in 37.5 million U.S. households. Shed fur can be criminal evidence because of transfer to victims, suspects, and/or their belongings. To improve cat hairs as forensic evidence, the mtDNA control region from single hairs, with and without root tags, was sequenced. A dataset of a 402-bp control region segment from 174 random-bred cats representing four U.S. geographic areas was generated to determine the informativeness of the mtDNA region. Thirty-two mtDNA mitotypes were observed ranging in frequencies from 0.6-27%. Four common types occurred in all populations. Low heteroplasmy, 1.7%, was determined. Unique mitotypes were found in 18 individuals, 10.3% of the population studied. The calculated discrimination power implied that 8.3 of 10 randomly selected individuals can be excluded by this region. The genetic characteristics of the region and the generated dataset support the use of this cat mtDNA region in forensic applications. 2010 American Academy of Forensic Sciences. Published 2010. This article is a U.S. Government work and is in the public domain in the U.S.A.

  8. Increased levels of mitochondrial DNA copy number in patients with vitiligo.

    Science.gov (United States)

    Vaseghi, H; Houshmand, M; Jadali, Z

    2017-10-01

    Oxidative stress is known to be involved in the pathogenesis of autoimmune diseases such as vitiligo. Evidence suggests that the human mitochondrial DNA copy number (mtDNAcn) is vulnerable to damage mediated by oxidative stress. The purpose of this study was to examine and compare peripheral blood mtDNAcn and oxidative DNA damage byproducts (8-hydroxy-2-deoxyguanosine; 8-OHdG) in patients with vitiligo and healthy controls (HCs). The relative mtDNAcn and the oxidative damage (formation of 8-OHdG in mtDNA) of each sample were determined by real-time quantitative PCR. Blood samples were obtained from 56 patients with vitiligo and 46 HCs. The mean mtDNAcn and the degree of mtDNA damage were higher in patients with vitiligo than in HCs. These data suggest that increase in mtDNAcn and oxidative DNA damage may be involved in the pathogenesis of vitiligo. © 2017 British Association of Dermatologists.

  9. Sequence homology at the breakpoint and clinical phenotype of mitochondrial DNA deletion syndromes.

    Science.gov (United States)

    Sadikovic, Bekim; Wang, Jing; El-Hattab, Ayman W; Landsverk, Megan; Douglas, Ganka; Brundage, Ellen K; Craigen, William J; Schmitt, Eric S; Wong, Lee-Jun C

    2010-12-20

    Mitochondrial DNA (mtDNA) deletions are a common cause of mitochondrial disorders. Large mtDNA deletions can lead to a broad spectrum of clinical features with different age of onset, ranging from mild mitochondrial myopathies (MM), progressive external ophthalmoplegia (PEO), and Kearns-Sayre syndrome (KSS), to severe Pearson syndrome. The aim of this study is to investigate the molecular signatures surrounding the deletion breakpoints and their association with the clinical phenotype and age at onset. MtDNA deletions in 67 patients were characterized using array comparative genomic hybridization (aCGH) followed by PCR-sequencing of the deletion junctions. Sequence homology including both perfect and imperfect short repeats flanking the deletion regions were analyzed and correlated with clinical features and patients' age group. In all age groups, there was a significant increase in sequence homology flanking the deletion compared to mtDNA background. The youngest patient group (deletion distribution in size and locations, with a significantly lower sequence homology flanking the deletion, and the highest percentage of deletion mutant heteroplasmy. The older age groups showed rather discrete pattern of deletions with 44% of all patients over 6 years old carrying the most common 5 kb mtDNA deletion, which was found mostly in muscle specimens (22/41). Only 15% (3/20) of the young patients (deletion, which is usually present in blood rather than muscle. This group of patients predominantly (16 out of 17) exhibit multisystem disorder and/or Pearson syndrome, while older patients had predominantly neuromuscular manifestations including KSS, PEO, and MM. In conclusion, sequence homology at the deletion flanking regions is a consistent feature of mtDNA deletions. Decreased levels of sequence homology and increased levels of deletion mutant heteroplasmy appear to correlate with earlier onset and more severe disease with multisystem involvement.

  10. Mitochondrial DNA copy number and chronic lymphocytic leukemia/small lymphocytic lymphoma risk in two prospective studies

    NARCIS (Netherlands)

    Kim, Christopher; Bassig, Bryan A; Seow, Wei Jie; Hu, Wei; Purdue, Mark P; Huang, Wen-Yi; Liu, Chin-San; Cheng, Wen-Ling; Männistö, Satu; Vermeulen, Roel; Weinstein, Stephanie J; Lim, Unhee; Hosgood, H Dean; Bonner, Matthew R; Caporaso, Neil E; Albanes, Demetrius; Lan, Qing; Rothman, Nathaniel

    BACKGROUND: Mitochondrial DNA copy number (mtDNA CN) may be modified by mitochondria in response to oxidative stress. Previously, mtDNA CN was associated with non-Hodgkin lymphoma (NHL) risk, particularly chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). We conducted a replication

  11. Characterizing nuclear and mitochondrial DNA in spent embryo culture media: genetic contamination identified.

    Science.gov (United States)

    Hammond, Elizabeth R; McGillivray, Brent C; Wicker, Sophie M; Peek, John C; Shelling, Andrew N; Stone, Peter; Chamley, Larry W; Cree, Lynsey M

    2017-01-01

    To characterize nuclear and mitochondrial DNA (mtDNA) in spent culture media from normally developing blastocysts to determine whether it could be used for noninvasive genetic assessment. Prospective embryo cohort study. Academic center and private in vitro fertilization (IVF) clinic. Seventy patients undergoing intracytoplasmic sperm injection (ICSI) and 227 blastocysts. Culture media assessment, artificial blastocoele fluid collapse and DNA analysis using digital polymerase chain reaction (dPCR), long-range PCR, quantitative PCR (qPCR), and DNA fingerprinting. Presence of nuclear and mtDNA in three different commercial culture media from Vitrolife and Irvine Scientific, spent embryo media assessment at the cleavage and blastocyst stages of development, and analysis of the internal media controls for each patient that had been exposed to identical conditions as embryo media but did not come into contact with embryos. Higher levels of nuclear and mtDNA were observed in the culture media that had been exposed to embryos compared with the internal media controls. Nuclear DNA (∼4 copies) and mtDNA (∼600 copies) could be detected in spent media, and the levels increased at the blastocyst stage. No increase in DNA was detected after artificial blastocoele fluid collapse. Mixed sex chromosome DNA was detected. This originated from contamination in the culture media and from maternal (cumulus) cells. Due to the limited amount of template, the presence of embryonic nuclear DNA could not be confirmed by DNA fingerprinting analysis. Currently DNA from culture media cannot be used for genetic assessment because embryo-associated structures release DNA into the culture medium and the DNA is of mixed origin. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  12. A test of the transcription model for biased inheritance of yeast mitochondrial DNA.

    Science.gov (United States)

    Lorimer, H E; Brewer, B J; Fangman, W L

    1995-09-01

    Two strand-specific origins of replication appear to be required for mammalian mitochondrial DNA (mtDNA) replication. Structural equivalents of these origins are found in the rep sequences of Saccharomyces cerevisiae mtDNA. These striking similarities have contributed to a universal model for the initiation of mtDNA replication in which a primer is created by cleavage of an origin region transcript. Consistent with this model are the properties of deletion mutants of yeast mtDNA ([rho-]) with a high density of reps (HS [rho-]). These mutant mtDNAs are preferentially inherited by the progeny resulting from the mating of HS [rho-] cells with cells containing wild-type mtDNA ([rho+]). This bias is presumed to result from a replication advantage conferred on HS [rho-] mtDNA by the high density of rep sequences acting as origins. To test whether transcription is indeed required for the preferential inheritance of HS [rho-] mtDNA, we deleted the nuclear gene (RPO41) for the mitochondrial RNA polymerase, reducing transcripts by at least 1000-fold. Since [rho-] genomes, but not [rho+] genomes, are stable when RPO41 is deleted, we examined matings between HS [rho-] and neutral [rho-] cells. Neutral [rho-] mtDNAs lack rep sequences and are not preferentially inherited in [rho-] x [rho+] crosses. In HS [rho-] x neutral [rho-] matings, the HS [rho-] mtDNA was preferentially inherited whether both parents were wild type or both were deleted for RPO41. Thus, transcription from the rep promoter does not appear to be necessary for biased inheritance. Our results, and analysis of the literature, suggest that priming by transcription is not a universal mechanism for mtDNA replication initiation.

  13. Ancient Resistome.

    Science.gov (United States)

    Olaitan, Abiola Olumuyiwa; Rolain, Jean-Marc

    2016-08-01

    Antibiotic resistance is an ancient biological mechanism in bacteria, although its proliferation in our contemporary world has been amplified through antimicrobial therapy. Recent studies conducted on ancient environmental and human samples have uncovered numerous antibiotic-resistant bacteria and resistance genes. The resistance genes that have been reported from the analysis of ancient bacterial DNA include genes coding for several classes of antibiotics, such as glycopeptides, β-lactams, tetracyclines, and macrolides. The investigation of the resistome of ancient bacteria is a recent and emerging field of research, and technological advancements such as next-generation sequencing will further contribute to its growth. It is hoped that the knowledge gained from this research will help us to better understand the evolution of antibiotic resistance genes and will also be used in drug design as a proactive measure against antibiotic resistance.

  14. Selective sweeps of mitochondrial DNA can drive the evolution of uniparental inheritance.

    Science.gov (United States)

    Christie, Joshua R; Beekman, Madeleine

    2017-08-01

    Although the uniparental (or maternal) inheritance of mitochondrial DNA (mtDNA) is widespread, the reasons for its evolution remain unclear. Two main hypotheses have been proposed: selection against individuals containing different mtDNAs (heteroplasmy) and selection against "selfish" mtDNA mutations. Recently, uniparental inheritance was shown to promote adaptive evolution in mtDNA, potentially providing a third hypothesis for its evolution. Here, we explore this hypothesis theoretically and ask if the accumulation of beneficial mutations provides a sufficient fitness advantage for uniparental inheritance to invade a population in which mtDNA is inherited biparentally. In a deterministic model, uniparental inheritance increases in frequency but cannot replace biparental inheritance if only a single beneficial mtDNA mutation sweeps through the population. When we allow successive selective sweeps of mtDNA, however, uniparental inheritance can replace biparental inheritance. Using a stochastic model, we show that a combination of selection and drift facilitates the fixation of uniparental inheritance (compared to a neutral trait) when there is only a single selective mtDNA sweep. When we consider multiple mtDNA sweeps in a stochastic model, uniparental inheritance becomes even more likely to replace biparental inheritance. Our findings thus suggest that selective sweeps of beneficial mtDNA haplotypes can drive the evolution of uniparental inheritance. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  15. Induction of Mitochondrial DNA Deletion by Ionizing Radiation in Human Lung Fibroblast IMR-90 Cells

    International Nuclear Information System (INIS)

    Eom, Hyeon Soo; Jung, U Hee; Park, Hae Ran; Jo, Sung Kee

    2009-01-01

    Mitochondrial DNA (mtDNA) deletion is a well-known marker for oxidative stress and aging and also contributes to their unfavorable effects in cultured cells and animal tissues. This study was conducted to investigate the effect of ionizing radiation (IR) on mtDNA deletion and the involvement of reactive oxygen species (ROS) in this process in human lung fibroblast (IMR-90) cells. Young IMR-90 cells at population doubling (PD) 39 were irradiated with 137 Cs -rays and the intracellular ROS level was determined by 2',7'-dichlorofluorescein diacetate (DCFH-DA) and mtDNA common deletion (4977bp) was detected by nested PCR. Old cells at PD 55 and H 2 O 2 -treated young cells were compared as the positive control. IR increased the intracellular ROS level and mtDNA 4977 bp deletion in IMR-90 cells dose-dependently. The increases of ROS level and mtDNA deletion were also observed in old cells and H 2 O 2 -treated young cells. To confirm the increased ROS level is essential for mtDNA deletion in irradiated cells, the effects of N-acetylcysteine (NAC) on IRinduced ROS and mtDNA deletion were examined. 5 mM NAC significantly attenuated the IR-induced ROS increase and mtDNA deletion. These results suggest that IR induces the mtDNA deletion and this process is mediated by ROS in IMR-90 cells

  16. Induction of Mitochondrial DNA Deletion by Ionizing Radiation in Human Lung Fibroblast IMR-90 Cells

    Energy Technology Data Exchange (ETDEWEB)

    Eom, Hyeon Soo; Jung, U Hee; Park, Hae Ran; Jo, Sung Kee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-06-15

    Mitochondrial DNA (mtDNA) deletion is a well-known marker for oxidative stress and aging and also contributes to their unfavorable effects in cultured cells and animal tissues. This study was conducted to investigate the effect of ionizing radiation (IR) on mtDNA deletion and the involvement of reactive oxygen species (ROS) in this process in human lung fibroblast (IMR-90) cells. Young IMR-90 cells at population doubling (PD) 39 were irradiated with {sup 137}Cs -rays and the intracellular ROS level was determined by 2',7'-dichlorofluorescein diacetate (DCFH-DA) and mtDNA common deletion (4977bp) was detected by nested PCR. Old cells at PD 55 and H{sub 2}O{sub 2}-treated young cells were compared as the positive control. IR increased the intracellular ROS level and mtDNA 4977 bp deletion in IMR-90 cells dose-dependently. The increases of ROS level and mtDNA deletion were also observed in old cells and H{sub 2}O{sub 2}-treated young cells. To confirm the increased ROS level is essential for mtDNA deletion in irradiated cells, the effects of N-acetylcysteine (NAC) on IRinduced ROS and mtDNA deletion were examined. 5 mM NAC significantly attenuated the IR-induced ROS increase and mtDNA deletion. These results suggest that IR induces the mtDNA deletion and this process is mediated by ROS in IMR-90 cells.

  17. RPO41-independent maintenance of [rho-] mitochondrial DNA in Saccharomyces cerevisiae.

    Science.gov (United States)

    Fangman, W L; Henly, J W; Brewer, B J

    1990-01-01

    A subset of promoters in the mitochondrial DNA (mtDNA) of the yeast Saccharomyces cerevisiae has been proposed to participate in replication initiation, giving rise to a primer through site-specific cleavage of an RNA transcript. To test whether transcription is essential for mtDNA maintenance, we examined two simple mtDNA deletion ([rho-]) genomes in yeast cells. One genome (HS3324) contains a consensus promoter (ATATAAGTA) for the mitochondrial RNA polymerase encoded by the nuclear gene RPO41, and the other genome (4a) does not. As anticipated, in RPO41 cells transcripts from the HS3324 genome were more abundant than were transcripts from the 4a genome. When the RPO41 gene was disrupted, both [rho-] genomes were efficiently maintained. The level of transcripts from HS3324 mtDNA was decreased greater than 400-fold in cells carrying the RPO41 disrupted gene; however, the low-level transcripts from 4a mtDNA were undiminished. These results indicate that replication of [rho-] genomes can be initiated in the absence of wild-type levels of the RPO41-encoded RNA polymerase.

  18. Regulation of Small Mitochondrial DNA Replicative Advantage by Ribonucleotide Reductase in Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Elliot Bradshaw

    2017-09-01

    Full Text Available Small mitochondrial genomes can behave as selfish elements by displacing wild-type genomes regardless of their detriment to the host organism. In the budding yeast Saccharomyces cerevisiae, small hypersuppressive mtDNA transiently coexist with wild-type in a state of heteroplasmy, wherein the replicative advantage of the small mtDNA outcompetes wild-type and produces offspring without respiratory capacity in >95% of colonies. The cytosolic enzyme ribonucleotide reductase (RNR catalyzes the rate-limiting step in dNTP synthesis and its inhibition has been correlated with increased petite colony formation, reflecting loss of respiratory function. Here, we used heteroplasmic diploids containing wild-type (rho+ and suppressive (rho− or hypersuppressive (HS rho− mitochondrial genomes to explore the effects of RNR activity on mtDNA heteroplasmy in offspring. We found that the proportion of rho+ offspring was significantly increased by RNR overexpression or deletion of its inhibitor, SML1, while reducing RNR activity via SML1 overexpression produced the opposite effects. In addition, using Ex Taq and KOD Dash polymerases, we observed a replicative advantage for small over large template DNA in vitro, but only at low dNTP concentrations. These results suggest that dNTP insufficiency contributes to the replicative advantage of small mtDNA over wild-type and cytosolic dNTP synthesis by RNR is an important regulator of heteroplasmy involving small mtDNA molecules in yeast.

  19. Mitochondrial mosaics in the liver of 3 infants with mtDNA defects

    Directory of Open Access Journals (Sweden)

    Scalais Emmanuel

    2009-06-01

    Full Text Available Abstract Background In muscle cytochrome oxidase (COX negative fibers (mitochondrial mosaics have often been visualized. Methods COX activity staining of liver for light and electron microscopy, muscle stains, blue native gel electrophoresis and activity assays of respiratory chain proteins, their immunolocalisation, mitochondrial and nuclear DNA analysis. Results Three unrelated infants showed a mitochondrial mosaic in the liver after staining for COX activity, i.e. hepatocytes with strongly reactive mitochondria were found adjacent to cells with many negative, or barely reactive, mitochondria. Deficiency was most severe in the patient diagnosed with Pearson syndrome. Ragged-red fibers were absent in muscle biopsies of all patients. Enzyme biochemistry was not diagnostic in muscle, fibroblasts and lymphocytes. Blue native gel electrophoresis of liver tissue, but not of muscle, demonstrated a decreased activity of complex IV; in both muscle and liver subcomplexes of complex V were seen. Immunocytochemistry of complex IV confirmed the mosaic pattern in two livers, but not in fibroblasts. MRI of the brain revealed severe white matter cavitation in the Pearson case, but only slight cortical atrophy in the Alpers-Huttenlocher patient, and a normal image in the 3rd. MtDNA in leucocytes showed a common deletion in 50% of the mtDNA molecules of the Pearson patient. In the patient diagnosed with Alpers-Huttenlocher syndrome, mtDNA was depleted for 60% in muscle. In the 3rd patient muscular and hepatic mtDNA was depleted for more than 70%. Mutations in the nuclear encoded gene of POLG were subsequently found in both the 2nd and 3rd patients. Conclusion Histoenzymatic COX staining of a liver biopsy is fast and yields crucial data about the pathogenesis; it indicates whether mtDNA should be assayed. Each time a mitochondrial disorder is suspected and muscle data are non-diagnostic, a liver biopsy should be recommended. Mosaics are probably more frequent

  20. Horizontal transfer of DNA from the mitochondrial to the plastid genome and its subsequent evolution in milkweeds (Apocynaceae)

    Science.gov (United States)

    Shannon C.K. Straub; Richard C. Cronn; Christopher Edwards; Mark Fishbein; Aaron. Liston

    2013-01-01

    Horizontal gene transfer (HGT) of DNA from the plastid to the nuclear and mitochondrial genomes of higher plants is a common phenomenon; however, plastid genomes (plastomes) are highly conserved and have generally been regarded as impervious to HGT. We sequenced the 158 kb plastome and the 690 kb mitochondrial genome of common milkweed (Asclepias syriaca [Apocynaceae...

  1. Ancient DNA analyses of museum specimens from selected Presbytis (primate: Colobinae) based on partial Cyt b sequences

    Science.gov (United States)

    Aifat, N. R.; Yaakop, S.; Md-Zain, B. M.

    2016-11-01

    The IUCN Red List of Threatened Species has categorized Malaysian primates from being data deficient to critically endanger. Thus, ancient DNA analyses hold great potential to understand phylogeny, phylogeography and population history of extinct and extant species. Museum samples are one of the alternatives to provide important sources of biological materials for a large proportion of ancient DNA studies. In this study, a total of six museum skin samples from species Presbytis hosei (4 samples) and Presbytis frontata (2 samples), aged between 43 and 124 years old were extracted to obtain the DNA. Extraction was done by using QIAGEN QIAamp DNA Investigator Kit and the ability of this kit to extract museum skin samples was tested by amplification of partial Cyt b sequence using species-specific designed primer. Two primer pairs were designed specifically for P. hosei and P. frontata, respectively. These primer pairs proved to be efficient in amplifying 200bp of the targeted species in the optimized PCR conditions. The performance of the sequences were tested to determine genetic distance of genus Presbytis in Malaysia. From the analyses, P. hosei is closely related to P. chrysomelas and P. frontata with the value of 0.095 and 0.106, respectively. Cyt b gave a clear data in determining relationships among Bornean species. Thus, with the optimized condition, museum specimens can be used for molecular systematic studies of the Malaysian primates.

  2. Is mitochondrial DNA divergence of near easter crested newts, Triturus karelinii group, reflected by differentiation of skull shape

    NARCIS (Netherlands)

    Ivanovic, A.; Uzum, N.; Wielstra, B.M.; Olgun, K.; Litvinchuk, S.N.; Kalezic, M.L.; Arntzen, J.W.

    2013-01-01

    The Eurasian Triturus karelinii group of crested newts comprises three distinct, geographically coherent mitochondrial DNA lineages, designated as the eastern, central and western lineage. These three lineages are genetically as diverged as other, morphologically well-differentiated crested newt

  3. Modulation of Mitochondrial DNA Copy Number to Induce Hepatocytic Differentiation of Human Amniotic Epithelial Cells.

    Science.gov (United States)

    Vaghjiani, Vijesh; Cain, Jason E; Lee, William; Vaithilingam, Vijayaganapathy; Tuch, Bernard E; St John, Justin C

    2017-10-15

    Mitochondrial deoxyribonucleic acid (mtDNA) copy number is tightly regulated during pluripotency and differentiation. There is increased demand of cellular adenosine triphosphate (ATP) during differentiation for energy-intensive cell types such as hepatocytes and neurons to meet the cell's functional requirements. During hepatocyte differentiation, mtDNA copy number should be synchronously increased to generate sufficient ATP through oxidative phosphorylation. Unlike bone marrow mesenchymal cells, mtDNA copy number failed to increase by 28 days of differentiation of human amniotic epithelial cells (hAEC) into hepatocyte-like cells (HLC) despite their expression of some end-stage hepatic markers. This was due to higher levels of DNA methylation at exon 2 of POLGA, the mtDNA-specific replication factor. Treatment with a DNA demethylation agent, 5-azacytidine, resulted in increased mtDNA copy number, reduced DNA methylation at exon 2 of POLGA, and reduced hepatic gene expression. Depletion of mtDNA followed by subsequent differentiation did not increase mtDNA copy number, but reduced DNA methylation at exon 2 of POLGA and increased expression of hepatic and pluripotency genes. We encapsulated hAEC in barium alginate microcapsules and subsequently differentiated them into HLC. Encapsulation resulted in no net increase of mtDNA copy number but a significant reduction in DNA methylation of POLGA. RNAseq analysis showed that differentiated HLC express hepatocyte-specific genes but also increased expression of inflammatory interferon genes. Differentiation in encapsulated cells showed suppression of inflammatory genes as well as increased expression of genes associated with hepatocyte function pathways and networks. This study demonstrates that an increase in classical hepatic gene expression can be achieved in HLC through encapsulation, although they fail to effectively regulate mtDNA copy number.

  4. Genetic characteristics and migration history of a bronze culture population in the West Liao-River valley revealed by ancient DNA.

    Science.gov (United States)

    Li, Hongjie; Zhao, Xin; Zhao, Yongbin; Li, Chunxiang; Si, Dayong; Zhou, Hui; Cui, Yinqiu

    2011-12-01

    In order to study the genetic characteristics of the Lower Xiajiadian culture (LXC) population, a main bronze culture branch in northern China dated 4500-3500 years ago, two uniparentally inherited markers, mitochondrial DNA and Y-chromosome single-nucleotide polymorphisms (Y-SNPs), were analyzed on 14 human remains excavated from the Dadianzi site. The 14 sequences, which contained 13 haplotypes, were assigned to 9 haplogroups, and Y-SNP typing of 5 male individuals assigned them to haplogroups N (M231) and O3 (M122). The results indicate that the LXC population mainly included people carrying haplogroups from northern Asia who had lived in this region since the Neolithic period, as well as genetic evidence of immigration from the Central Plain. Later in the Bronze Age, part of the population migrated to the south away from a cooler climate, which ultimately influenced the gene pool in the Central Plain. Thus, climate change is an important factor, which drove the population migration during the Bronze Age in northern China. Based on these results, the local genetic continuity did not seem to be affected by outward migration, although more data are needed especially from other ancient populations to determine the influence of return migration on genetic continuity.

  5. Nickel exposure induces oxidative damage to mitochondrial DNA in Neuro2a cells: the neuroprotective roles of melatonin.

    Science.gov (United States)

    Xu, Shang-Cheng; He, Min-Di; Lu, Yong-Hui; Li, Li; Zhong, Min; Zhang, Yan-Wen; Wang, Yuan; Yu, Zheng-Ping; Zhou, Zhou

    2011-11-01

    Recent studies suggest that oxidative stress and mitochondrial dysfunction play important roles in the neurotoxicity of nickel. Because mitochondrial DNA (mtDNA) is highly vulnerable to oxidative stress and melatonin can efficiently protect mtDNA against oxidative damage in various pathological conditions, the aims of this study were to determine whether mtDNA oxidative damage was involved in the neurotoxicity of nickel and to assay the neuroprotective effects of melatonin in mtDNA. In this study, we exposed mouse neuroblastoma cell lines (Neuro2a) to different concentrations of nickel chloride (NiCl(2), 0.125, 0.25, and 0.5 mm) for 24 hr. We found that nickel significantly increased reactive oxygen species (ROS) production and mitochondrial superoxide levels. In addition, nickel exposure increased mitochondrial 8-hydroxyguanine (8-OHdG) content and reduced mtDNA content and mtDNA transcript levels. Consistent with this finding, nickel was found to destroy mtDNA nucleoid structure and decrease protein levels of Tfam, a key protein component for nucleoid organization. However, all the oxidative damage to mtDNA induced by nickel was efficiently attenuated by melatonin pretreatment. Our results suggest that oxidative damage to mtDNA may account for the neurotoxicity of nickel. Melatonin has great pharmacological potential in protecting mtDNA against the adverse effects of nickel in the nervous system. © 2011 John Wiley & Sons A/S.

  6. [Relationship between mitochondrial DNA copy number, membrane potential of human embryo and embryo morphology].

    Science.gov (United States)

    Zhao, H; Teng, X M; Li, Y F

    2017-11-25

    Objective: To explore the relationship between the embryo with the different morphological types in the third day and its mitochondrial copy number, the membrane potential. Methods: Totally 117 embryos with poor development after normal fertilization and were not suitable transferred in the fresh cycle and 106 frozen embryos that were discarded voluntarily by infertility patients with in vitro fertilization-embryo transfer after successful pregnancy were selected. According to evaluation of international standard in embryos, all cleavage stage embryos were divided into class Ⅰ frozen embryo group ( n= 64), class Ⅱ frozen embryo group ( n= 42) and class Ⅲ fresh embryonic group (not transplanted embryos; n= 117). Real-time PCR and confocal microscopy methods were used to detect mitochondrial DNA (mtDNA) copy number and the mitochondrial membrane potential of a single embryo. The differences between embryo quality and mtDNA copy number and membrane potential of each group were compared. Results: The copy number of mtDNA and the mitochondrial membrane potential in class Ⅲ fresh embryonic group [(1.7±1.0)×10(5) copy/μl, 1.56±0.32] were significantly lower than those in class Ⅰ frozen embryo group [(3.4±1.7)×10(5) copy/μl, 2.66±0.21] and class Ⅱ frozen embryo group [(2.6±1.2)×10(5) copy/μl, 1.80±0.32; all Pembryo group were significantly higher than those in classⅡ frozen embryo group (both Pembryos of the better quality embryo are higher.

  7. Complete mitochondrial DNA sequence of the Eastern keelback mullet Liza affinis.

    Science.gov (United States)

    Gong, Xiaoling; Zhu, Wenjia; Bao, Baolong

    2016-05-01

    Eastern keelback mullet (Liza affinis) inhabits inlet waters and estuaries of rivers. In this paper, we initially determined the complete mitochondrial genome of Liza affinis. The entire mtDNA sequence is 16,831 bp in length, including 2 rRNA genes, 22 tRNA genes, 13 protein-coding genes and 1 putative control region. Its order and numbers of genes are similar to most bony fishes.

  8. Mitochondrial DNA and craniofacial covariability of Chad Basin females indicate past population events

    Czech Academy of Sciences Publication Activity Database

    Hájek, Martin; Černý, Viktor; Brůžek, J.

    2008-01-01

    Roč. 20, č. 4 (2008), s. 465-474 ISSN 1042-0533 R&D Projects: GA ČR GA206/08/1587 Institutional research plan: CEZ:AV0Z80020508 Keywords : craniofacial morphology * mitochondrial DNA * sub - Saharan Africa * population history Sub ject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 1.976, year: 2008 http://www3.interscience.wiley.com/journal/118903453/abstract?CRETRY=1&SRETRY=0

  9. Scavenging Circulating Mitochondrial DNA as a Potential Therapeutic Option for Multiple Organ Dysfunction in Trauma Hemorrhage.

    Science.gov (United States)

    Aswani, Andrew; Manson, Joanna; Itagaki, Kiyoshi; Chiazza, Fausto; Collino, Massimo; Wupeng, Winston Liao; Chan, Tze Khee; Wong, W S Fred; Hauser, Carl J; Thiemermann, Chris; Brohi, Karim

    2018-01-01

    Trauma is a leading cause of death worldwide with 5.8 million deaths occurring yearly. Almost 40% of trauma deaths are due to bleeding and occur in the first few hours after injury. Of the remaining severely injured patients up to 25% develop a dysregulated immune response leading to multiple organ dysfunction syndrome (MODS). Despite improvements in trauma care, the morbidity and mortality of this condition remains very high. Massive traumatic injury can overwhelm endogenous homeostatic mechanisms even with prompt treatment. The underlying mechanisms driving MODS are also not fully elucidated. As a result, successful therapies for trauma-related MODS are lacking. Trauma causes tissue damage that releases a large number of endogenous damage-associated molecular patterns (DAMPs). Mitochondrial DAMPs released in trauma, such as mitochondrial DNA (mtDNA), could help to explain part of the immune response in trauma given the structural similarities between mitochondria and bacteria. MtDNA, like bacterial DNA, contains an abundance of highly stimulatory unmethylated CpG DNA motifs that signal through toll-like receptor-9 to produce inflammation. MtDNA has been shown to be highly damaging when injected into healthy animals causing acute organ injury to develop. Elevated circulating levels of mtDNA have been reported in trauma patients but an association with clinically meaningful outcomes has not been established in a large cohort. We aimed to determine whether mtDNA released after clinical trauma hemorrhage is sufficient for the development of MODS. Secondly, we aimed to determine the extent of mtDNA release with varying degrees of tissue injury and hemorrhagic shock in a clinically relevant rodent model. Our final aim was to determine whether neutralizing mtDNA with the nucleic acid scavenging polymer, hexadimethrine bromide (HDMBr), at a clinically relevant time point in vivo would reduce the severity of organ injury in this model. We have shown that the release of mtDNA

  10. Scavenging Circulating Mitochondrial DNA as a Potential Therapeutic Option for Multiple Organ Dysfunction in Trauma Hemorrhage

    Directory of Open Access Journals (Sweden)

    Andrew Aswani

    2018-05-01

    Full Text Available Trauma is a leading cause of death worldwide with 5.8 million deaths occurring yearly. Almost 40% of trauma deaths are due to bleeding and occur in the first few hours after injury. Of the remaining severely injured patients up to 25% develop a dysregulated immune response leading to multiple organ dysfunction syndrome (MODS. Despite improvements in trauma care, the morbidity and mortality of this condition remains very high. Massive traumatic injury can overwhelm endogenous homeostatic mechanisms even with prompt treatment. The underlying mechanisms driving MODS are also not fully elucidated. As a result, successful therapies for trauma-related MODS are lacking. Trauma causes tissue damage that releases a large number of endogenous damage-associated molecular patterns (DAMPs. Mitochondrial DAMPs released in trauma, such as mitochondrial DNA (mtDNA, could help to explain part of the immune response in trauma given the structural similarities between mitochondria and bacteria. MtDNA, like bacterial DNA, contains an abundance of highly stimulatory unmethylated CpG DNA motifs that signal through toll-like receptor-9 to produce inflammation. MtDNA has been shown to be highly damaging when injected into healthy animals causing acute organ injury to develop. Elevated circulating levels of mtDNA have been reported in trauma patients but an association with clinically meaningful outcomes has not been established in a large cohort. We aimed to determine whether mtDNA released after clinical trauma hemorrhage is sufficient for the development of MODS. Secondly, we aimed to determine the extent of mtDNA release with varying degrees of tissue injury and hemorrhagic shock in a clinically relevant rodent model. Our final aim was to determine whether neutralizing mtDNA with the nucleic acid scavenging polymer, hexadimethrine bromide (HDMBr, at a clinically relevant time point in vivo would reduce the severity of organ injury in this model. Conclusions: We have

  11. Mitochondrial DNA heteroplasmy in ovine fetuses and sheep cloned by somatic cell nuclear transfer

    Directory of Open Access Journals (Sweden)

    Müller Mathias

    2007-12-01

    Full Text Available Abstract Background The mitochondrial DNA (mtDNA of the cloned sheep "Dolly" and nine other ovine clones produced by somatic cell nuclear transfer (SCNT was reported to consist only of recipient oocyte mtDNA without any detectable mtDNA contribution from the nucleus donor cell. In cattle, mouse and pig several or most of the clones showed transmission of nuclear donor mtDNA resulting in mitochondrial heteroplasmy. To clarify the discrepant transmission pattern of donor mtDNA in sheep clones we analysed the mtDNA composition of seven fetuses and five lambs cloned from fetal fibroblasts. Results The three fetal fibroblast donor cells used for SCNT harboured low mtDNA copy numbers per cell (A: 753 ± 54, B: 292 ± 33 and C: 561 ± 88. The ratio of donor to recipient oocyte mtDNAs was determined using a quantitative amplification refractory mutation system (ARMS PCR (i.e. ARMS-qPCR. For quantification of SNP variants with frequencies below 0.1% we developed a restriction endonuclease-mediated selective quantitative PCR (REMS-qPCR. We report the first cases (n = 4 fetuses, n = 3 lambs of recipient oocyte/nuclear donor mtDNA heteroplasmy in SCNT-derived ovine clones demonstrating that there is no species-effect hindering ovine nucleus-donor mtDNA from being transmitted to the somatic clonal offspring. Most of the heteroplasmic clones exhibited low-level heteroplasmy (0.1% to 0.9%, n = 6 indicating neutral transmission of parental mtDNAs. High-level heteroplasmy (6.8% to 46.5% was observed in one case. This clone possessed a divergent recipient oocyte-derived mtDNA genotype with three rare amino acid changes compared to the donor including one substitution at an evolutionary conserved site. Conclusion Our study using state-of-the-art techniques for mtDNA quantification, like ARMS-qPCR and the novel REMS-qPCR, documents for the first time the transmission of donor mtDNA into somatic sheep clones. MtDNA heteroplasmy was detected in seven of 12 clones

  12. Evolution of mitochondrial DNA and its relation to basal metabolic rate.

    Science.gov (United States)

    Feng, Ping; Zhao, Huabin; Lu, Xin

    2015-08-01

    Energy metabolism is essential for the survival of animals, which can be characterized by maximum metabolic rate (MMR) and basal metabolic rate (BMR). Because of the crucial roles of mitochondria in energy metabolism, mitochondrial DNA (mtDNA) has been subjected to stronger purifying selection in strongly locomotive than weakly locomotive birds and mammals. Although maximum locomotive speed (an indicator of MMR) showed a negative correlation with the evolutionary rate of mtDNA, it is unclear whether BMR has driven the evolution of mtDNA. Here, we take advantage of the large amount of mtDNA and BMR data in 106 mammals to test whether BMR has influenced the mtDNA evolution. Our results showed that, in addition to the locomotive speed, mammals with higher BMR have subjected to stronger purifying selection on mtDNA than did those with lower BMR. The evolution of mammalian mtDNA has been modified by two levels of energy metabolism, including MMR and BMR. Our study provides a more comprehensive view of mtDNA evolution in relation to energy metabolism.

  13. Genetic diversity and differentiation in Prunus species (Rosaceae) using chloroplast and mitochondrial DNA CAPS markers.

    Science.gov (United States)

    Ben Mustapha, S; Ben Tamarzizt, H; Baraket, G; Abdallah, D; Salhi Hannachi, A

    2015-04-27

    Chloroplast (cpDNA) and mitochondrial DNA (mtDNA) were analyzed to establish genetic relationships among Tunisian plum cultivars using the polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) technique. Two mtDNA regions (nad 1 b/c and nad 4 1/2) and a cpDNA region (trnL-trnF) were amplified and digested using restriction enzymes. Seventy and six polymorphic sites were revealed in cpDNA and mtDNA, respectively. As a consequence, cpDNA appears to be more polymorphic than mtDNA. The unweighted pair group method with arithmetic mean (UPGMA) dendrogram showed that accessions were distributed independently of their geographical origin, and introduced and local cultivars appear to be closely related. Both UPGMA and principal component analysis grouped Tunisian plum accessions into similar clusters. The analysis of the pooled sequences allowed the detection of 17 chlorotypes and 12 mitotypes. The unique haplotypes detected for cultivars are valuable for management and preservation of the plum local resources. From this study, PCR-RFLP analysis appears to be a useful approach to detect and identify cytoplasmic variation in plum trees. Our results also provide useful information for the management of genetic resources and to establish a program to improve the genetic resources available for plums.

  14. [Polymorphisms of mitochondrial DNA hypervariable regions HVR I and HVR II in Changdu Tibetan in China].

    Science.gov (United States)

    Zhao, Jianmin; Kang, Longli; Bian, Liqiang; La, Zong

    2008-10-01

    To analyze the sequence polymorphisms of mitochondrial DNA HVR I and HVR II in Tibetan population in Changdu area of Tibet. mtDNAs obtained from 97 unrelated individuals were amplified and directly sequenced. One hundred and eleven variable sites were identified, including nucleotide transitions, transversions, insertions and deletions. In HVR I region (nt16024-nt16365), sixty-eight polymorphic sites and 92 haplotypes were observed, and the genetic diversity was 0.9985. In HVR II region (nt73-nt340), forty-three polymorphic sites and 91 haplotypes were detected, and the genetic diversity was 0.9882. The random match probability of HVR I and HVR II regions were 0.0120 and 0.0118, respectively. When the sequence analysis of HVR I and HVR II regions were combined, ninety-seven different haplotypes were found. The combined match probability of two unrelated persons having the same sequence was 0.0103. There are some unique polymorphic loci in the Changdu Tibetan population. The results suggest that there are significant difference in the genetic structure in the mitochondrial DNA D-loop region between Changdu Tibetans and other Asian populations and Caucasians. Sequence polymorphism in mitochondrial DNA HVR I and HVR II can be used as a genetic marker for forensic individual identification and genetic analysis.

  15. Plastome Sequencing of Ten Nonmodel Crop Species Uncovers a Large Insertion of Mitochondrial DNA in Cashew.

    Science.gov (United States)

    Rabah, Samar O; Lee, Chaehee; Hajrah, Nahid H; Makki, Rania M; Alharby, Hesham F; Alhebshi, Alawiah M; Sabir, Jamal S M; Jansen, Robert K; Ruhlman, Tracey A

    2017-11-01

    In plant evolution, intracellular gene transfer (IGT) is a prevalent, ongoing process. While nuclear and mitochondrial genomes are known to integrate foreign DNA via IGT and horizontal gene transfer (HGT), plastid genomes (plastomes) have resisted foreign DNA incorporation and only recently has IGT been uncovered in the plastomes of a few land plants. In this study, we completed plastome sequences for l0 crop species and describe a number of structural features including variation in gene and intron content, inversions, and expansion and contraction of the inverted repeat (IR). We identified a putative in cinnamon ( J. Presl) and other sequenced Lauraceae and an apparent functional transfer of to the nucleus of quinoa ( Willd.). In the orchard tree cashew ( L.), we report the insertion of an ∼6.7-kb fragment of mitochondrial DNA into the plastome IR. BLASTn analyses returned high identity hits to mitogenome sequences including an intact open reading frame. Using three plastome markers for five species of , we generated a phylogeny to investigate the distribution and timing of the insertion. Four species share the insertion, suggesting that this event occurred <20 million yr ago in a single clade in the genus. Our study extends the observation of mitochondrial to plastome IGT to include long-lived tree species. While previous studies have suggested possible mechanisms facilitating IGT to the plastome, more examples of this phenomenon, along with more complete mitogenome sequences, will be required before a common, or variable, mechanism can be elucidated. Copyright © 2017 Crop Science Society of America.

  16. Mitochondrial DNA sequence data reveals association of haplogroup U with psychosis in bipolar disorder.

    Science.gov (United States)

    Frye, Mark A; Ryu, Euijung;