1
|
Libring S, Berestesky ED, Reinhart-King CA. The movement of mitochondria in breast cancer: internal motility and intercellular transfer of mitochondria. Clin Exp Metastasis 2024:10.1007/s10585-024-10269-3. [PMID: 38489056 DOI: 10.1007/s10585-024-10269-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 01/18/2024] [Indexed: 03/17/2024]
Abstract
As a major energy source for cells, mitochondria are involved in cell growth and proliferation, as well as migration, cell fate decisions, and many other aspects of cellular function. Once thought to be irreparably defective, mitochondrial function in cancer cells has found renewed interest, from suggested potential clinical biomarkers to mitochondria-targeting therapies. Here, we will focus on the effect of mitochondria movement on breast cancer progression. Mitochondria move both within the cell, such as to localize to areas of high energetic need, and between cells, where cells within the stroma have been shown to donate their mitochondria to breast cancer cells via multiple methods including tunneling nanotubes. The donation of mitochondria has been seen to increase the aggressiveness and chemoresistance of breast cancer cells, which has increased recent efforts to uncover the mechanisms of mitochondrial transfer. As metabolism and energetics are gaining attention as clinical targets, a better understanding of mitochondrial function and implications in cancer are required for developing effective, targeted therapeutics for cancer patients.
Collapse
Affiliation(s)
- Sarah Libring
- Department of Biomedical Engineering, Vanderbilt University, 440 Engineering and Science Building, 1212 25thAvenue South, Nashville, TN, 37235, USA
| | - Emily D Berestesky
- Department of Biomedical Engineering, Vanderbilt University, 440 Engineering and Science Building, 1212 25thAvenue South, Nashville, TN, 37235, USA
| | - Cynthia A Reinhart-King
- Department of Biomedical Engineering, Vanderbilt University, 440 Engineering and Science Building, 1212 25thAvenue South, Nashville, TN, 37235, USA.
| |
Collapse
|
2
|
Rehman A, Kumari R, Kamthan A, Tiwari R, Srivastava RK, van der Westhuizen FH, Mishra PK. Cell-free circulating mitochondrial DNA: An emerging biomarker for airborne particulate matter associated with cardiovascular diseases. Free Radic Biol Med 2023; 195:103-120. [PMID: 36584454 DOI: 10.1016/j.freeradbiomed.2022.12.083] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 12/16/2022] [Accepted: 12/20/2022] [Indexed: 12/29/2022]
Abstract
The association of airborne particulate matter exposure with the deteriorating function of the cardiovascular system is fundamentally driven by the impairment of mitochondrial-nuclear crosstalk orchestrated by aberrant redox signaling. The loss of delicate balance in retrograde communication from mitochondria to the nucleus often culminates in the methylation of the newly synthesized strand of mitochondrial DNA (mtDNA) through DNA methyl transferases. In highly metabolic active tissues such as the heart, mtDNA's methylation state alteration impacts mitochondrial bioenergetics. It affects transcriptional regulatory processes involved in biogenesis, fission, and fusion, often accompanied by the integrated stress response. Previous studies have demonstrated a paradoxical role of mtDNA methylation in cardiovascular pathologies linked to air pollution. A pronounced alteration in mtDNA methylation contributes to systemic inflammation, an etiological determinant for several co-morbidities, including vascular endothelial dysfunction and myocardial injury. In the current article, we evaluate the state of evidence and examine the considerable promise of using cell-free circulating methylated mtDNA as a predictive biomarker to reduce the more significant burden of ambient air pollution on cardiovascular diseases.
Collapse
Affiliation(s)
- Afreen Rehman
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India.
| | - Roshani Kumari
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India.
| | - Arunika Kamthan
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India.
| | - Rajnarayan Tiwari
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India.
| | | | | | - Pradyumna Kumar Mishra
- Department of Molecular Biology, ICMR-National Institute for Research in Environmental Health, Bhopal, India.
| |
Collapse
|
3
|
High-frequency and functional mitochondrial DNA mutations at the single-cell level. Proc Natl Acad Sci U S A 2023; 120:e2201518120. [PMID: 36577067 PMCID: PMC9910596 DOI: 10.1073/pnas.2201518120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Decline in mitochondrial function underlies aging and age-related diseases, but the role of mitochondrial DNA (mtDNA) mutations in these processes remains elusive. To investigate patterns of mtDNA mutations, it is particularly important to quantify mtDNA mutations and their associated pathogenic effects at the single-cell level. However, existing single-cell mtDNA sequencing approaches remain inefficient due to high cost and low mtDNA on-target rates. In this study, we developed a cost-effective mtDNA targeted-sequencing protocol called single-cell sequencing by targeted amplification of multiplex probes (scSTAMP) and experimentally validated its reliability. We then applied our method to assess single-cell mtDNA mutations in 768 B lymphocytes and 768 monocytes from a 76-y-old female. Across 632 B lymphocyte and 617 monocytes with medium mtDNA coverage over >100×, our results indicated that over 50% of cells carried at least one mtDNA mutation with variant allele frequencies (VAFs) over 20%, and that cells carried an average of 0.658 and 0.712 such mutation for B lymphocytes and monocytes, respectively. Surprisingly, more than 20% of the observed mutations had VAFs of over 90% in either cell population. In addition, over 60% of the mutations were in protein-coding genes, of which over 70% were nonsynonymous, and more than 50% of the nonsynonymous mutations were predicted to be highly pathogenic. Interestingly, about 80% of the observed mutations were singletons in the respective cell populations. Our results revealed mtDNA mutations with functional significance might be prevalent at advanced age, calling further investigation on age-related mtDNA mutation dynamics at the single-cell level.
Collapse
|
4
|
Assessment of mitochondrial DNA viability ratio in day-4 biopsied embryos as an add-in to select euploid embryos for single embryo transfer. ZYGOTE 2022; 30:790-796. [PMID: 36148882 DOI: 10.1017/s0967199422000260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The aim of this study was to assess mitochondrial DNA analysis as a predictor of the pregnancy potential of biopsied preimplantation embryos. The study included 78 blastomeres biopsied from day 4 cleavage stage euploid embryos. The embryo karyotype was confirmed by 24-chromosome preimplantation genetic testing for aneuploidies using the Illumina Next-Generation Sequencing (NGS) system. Mitochondria viability ratios (mtV) were determined from BAM files subjected to the web-based genome-analysis tool Galaxy. From this cohort of patients, 30.4% of patients (n = 34) failed to establish pregnancy. The mean mtV ratio [mean = 1.51 ± 1.25-1.77 (95% CI)] for this group was significantly (P < 0.01) lower compared with the embryo population that resulted in established pregnancies [mean = 2.5 ± 1.82-2.68 (95% CI)]. mtV multiple of mean (MoM) values were similarly significantly (P < 0.01) lower in blastocysts failing to establish pregnancy. At a 0.5 MoM cut-off, the sensitivity of mtV quantitation was 35.3% and specificity was 78.2%. The positive predictive value for an mtV value > 0.5 MoM was 41.4%. This study demonstrates the clinical utility of preimplantation quantification of viable mitochondrial DNA in biopsied blastomeres as a prognosticator of pregnancy potential.
Collapse
|
5
|
Ye Z, Zhao C, Raborn RT, Lin M, Wei W, Hao Y, Lynch M. Genetic Diversity, Heteroplasmy, and Recombination in Mitochondrial Genomes of Daphnia pulex, Daphnia pulicaria, and Daphnia obtusa. Mol Biol Evol 2022; 39:6553573. [PMID: 35325186 PMCID: PMC9004417 DOI: 10.1093/molbev/msac059] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Genetic variants of mitochondrial DNA at the individual (heteroplasmy) and population (polymorphism) levels provide insight into their roles in multiple cellular and evolutionary processes. However, owing to the paucity of genome-wide data at the within-individual and population levels, the broad patterns of these two forms of variation remain poorly understood. Here, we analyze 1,804 complete mitochondrial genome sequences from Daphnia pulex, Daphnia pulicaria, and Daphnia obtusa. Extensive heteroplasmy is observed in D. obtusa, where the high level of intraclonal divergence must have resulted from a biparental-inheritance event, and recombination in the mitochondrial genome is apparent, although perhaps not widespread. Global samples of D. pulex reveal remarkably low mitochondrial effective population sizes, <3% of those for the nuclear genome. In addition, levels of population diversity in mitochondrial and nuclear genomes are uncorrelated across populations, suggesting an idiosyncratic evolutionary history of mitochondria in D. pulex. These population-genetic features appear to be a consequence of background selection associated with highly deleterious mutations arising in the strongly linked mitochondrial genome, which is consistent with polymorphism and divergence data suggesting a predominance of strong purifying selection. Nonetheless, the fixation of mildly deleterious mutations in the mitochondrial genome also appears to be driving positive selection on genes encoded in the nuclear genome whose products are deployed in the mitochondrion.
Collapse
Affiliation(s)
- Zhiqiang Ye
- Center for Mechanisms of Evolution, Biodesign Institute, Arizona State University, Tempe, AZ, 85287
| | - Chaoxian Zhao
- Center for Mechanisms of Evolution, Biodesign Institute, Arizona State University, Tempe, AZ, 85287
| | - R Taylor Raborn
- Center for Mechanisms of Evolution, Biodesign Institute, Arizona State University, Tempe, AZ, 85287
| | - Man Lin
- Center for Mechanisms of Evolution, Biodesign Institute, Arizona State University, Tempe, AZ, 85287
| | - Wen Wei
- Center for Mechanisms of Evolution, Biodesign Institute, Arizona State University, Tempe, AZ, 85287
| | - Yue Hao
- Center for Mechanisms of Evolution, Biodesign Institute, Arizona State University, Tempe, AZ, 85287
| | - Michael Lynch
- Center for Mechanisms of Evolution, Biodesign Institute, Arizona State University, Tempe, AZ, 85287
| |
Collapse
|
6
|
Meshnik L, Bar-Yaacov D, Kasztan D, Neiger T, Cohen T, Kishner M, Valenci I, Dadon S, Klein CJ, Vance JM, Nevo Y, Züchner S, Ovadia O, Mishmar D, Ben-Zvi A. Mutant C. elegans mitofusin leads to selective removal of mtDNA heteroplasmic deletions across generations to maintain fitness. BMC Biol 2022; 20:40. [PMID: 35139855 PMCID: PMC8829988 DOI: 10.1186/s12915-022-01241-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 01/28/2022] [Indexed: 11/20/2022] Open
Abstract
Background Mitochondrial DNA (mtDNA) is present at high copy numbers in animal cells, and though characterized by a single haplotype in each individual due to maternal germline inheritance, deleterious mutations and intact mtDNA molecules frequently co-exist (heteroplasmy). A number of factors, such as replicative segregation, mitochondrial bottlenecks, and selection, may modulate the exitance of heteroplasmic mutations. Since such mutations may have pathological consequences, they likely survive and are inherited due to functional complementation via the intracellular mitochondrial network. Here, we hypothesized that compromised mitochondrial fusion would hamper such complementation, thereby affecting heteroplasmy inheritance. Results We assessed heteroplasmy levels in three Caenorhabditis elegans strains carrying different heteroplasmic mtDNA deletions (ΔmtDNA) in the background of mutant mitofusin (fzo-1). Animals displayed severe embryonic lethality and developmental delay. Strikingly, observed phenotypes were relieved during subsequent generations in association with complete loss of ΔmtDNA molecules. Moreover, deletion loss rates were negatively correlated with the size of mtDNA deletions, suggesting that mitochondrial fusion is essential and sensitive to the nature of the heteroplasmic mtDNA mutations. Introducing the ΔmtDNA into a fzo-1;pdr-1;+/ΔmtDNA (PARKIN ortholog) double mutant resulted in a skewed Mendelian progeny distribution, in contrast to the normal distribution in the fzo-1;+/ΔmtDNA mutant, and severely reduced brood size. Notably, the ΔmtDNA was lost across generations in association with improved phenotypes. Conclusions Taken together, our findings show that when mitochondrial fusion is compromised, deleterious heteroplasmic mutations cannot evade natural selection while inherited through generations. Moreover, our findings underline the importance of cross-talk between mitochondrial fusion and mitophagy in modulating the inheritance of mtDNA heteroplasmy. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-022-01241-2.
Collapse
Affiliation(s)
- Lana Meshnik
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Dan Bar-Yaacov
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel.,Department of Microbiology, Immunology and Genetics, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Dana Kasztan
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Tali Neiger
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Tal Cohen
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Mor Kishner
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Itay Valenci
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Sara Dadon
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Christopher J Klein
- Department of Neurology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Jeffery M Vance
- Dr. John T. Macdonald Foundation Department of Human Genetics and Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Yoram Nevo
- Institute of Neurology, Schneider Children's Medical Center of Israel, Tel-Aviv University, Petach Tikva, Israel
| | - Stephan Züchner
- Dr. John T. Macdonald Foundation Department of Human Genetics and Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Ofer Ovadia
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Dan Mishmar
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Anat Ben-Zvi
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel.
| |
Collapse
|
7
|
Abstract
Variation in the mitochondrial DNA (mtDNA) sequence is common in certain tumours. Two classes of cancer mtDNA variants can be identified: de novo mutations that act as 'inducers' of carcinogenesis and functional variants that act as 'adaptors', permitting cancer cells to thrive in different environments. These mtDNA variants have three origins: inherited variants, which run in families, somatic mutations arising within each cell or individual, and variants that are also associated with ancient mtDNA lineages (haplogroups) and are thought to permit adaptation to changing tissue or geographic environments. In addition to mtDNA sequence variation, mtDNA copy number and perhaps transfer of mtDNA sequences into the nucleus can contribute to certain cancers. Strong functional relevance of mtDNA variation has been demonstrated in oncocytoma and prostate cancer, while mtDNA variation has been reported in multiple other cancer types. Alterations in nuclear DNA-encoded mitochondrial genes have confirmed the importance of mitochondrial metabolism in cancer, affecting mitochondrial reactive oxygen species production, redox state and mitochondrial intermediates that act as substrates for chromatin-modifying enzymes. Hence, subtle changes in the mitochondrial genotype can have profound effects on the nucleus, as well as carcinogenesis and cancer progression.
Collapse
Affiliation(s)
- Piotr K Kopinski
- Howard Hughes Medical Institute, University of Pennsylvania, Philadelphia, PA, USA
- Center for Mitochondrial and Epigenomic Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Larry N Singh
- Center for Mitochondrial and Epigenomic Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Shiping Zhang
- Center for Mitochondrial and Epigenomic Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Marie T Lott
- Center for Mitochondrial and Epigenomic Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Douglas C Wallace
- Center for Mitochondrial and Epigenomic Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
- Department of Pediatrics, Division of Human Genetics, The Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
8
|
Weissensteiner H, Forer L, Fendt L, Kheirkhah A, Salas A, Kronenberg F, Schoenherr S. Contamination detection in sequencing studies using the mitochondrial phylogeny. Genome Res 2021; 31:309-316. [PMID: 33452015 PMCID: PMC7849411 DOI: 10.1101/gr.256545.119] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 11/30/2020] [Indexed: 01/14/2023]
Abstract
Within-species contamination is a major issue in sequencing studies, especially for mitochondrial studies. Contamination can be detected by analyzing the nuclear genome or by inspecting polymorphic sites in the mitochondrial genome (mtDNA). Existing methods using the nuclear genome are computationally expensive, and no appropriate tool for detecting sample contamination in large-scale mtDNA data sets is available. Here we present haplocheck, a tool that requires only the mtDNA to detect contamination in both targeted mitochondrial and whole-genome sequencing studies. Our in silico simulations and amplicon mixture experiments indicate that haplocheck detects mtDNA contamination accurately and is independent of the phylogenetic distance within a sample mixture. By applying haplocheck to The 1000 Genomes Project Consortium data, we further evaluate the application of haplocheck as a fast proxy tool for nDNA-based contamination detection using the mtDNA and identify the mitochondrial copy number within a mixture as a critical component for the overall accuracy. The haplocheck tool is available both as a command-line tool and as a cloud web service producing interactive reports that facilitates the navigation through the phylogeny of contaminated samples.
Collapse
Affiliation(s)
- Hansi Weissensteiner
- Institute of Genetic Epidemiology, Department of Genetics and Pharmacology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Lukas Forer
- Institute of Genetic Epidemiology, Department of Genetics and Pharmacology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Liane Fendt
- Institute of Genetic Epidemiology, Department of Genetics and Pharmacology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Azin Kheirkhah
- Institute of Genetic Epidemiology, Department of Genetics and Pharmacology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Antonio Salas
- Unidade de Xenética, Instituto de Ciencias Forenses (INCIFOR), Facultade de Medicina, Universidade de Santiago de Compostela, and GenPoB Research Group, Instituto de Sanitarias (IDIS), Hospital Clínico Universitario de Santiago (SERGAS), 15782, Galicia, Spain
| | - Florian Kronenberg
- Institute of Genetic Epidemiology, Department of Genetics and Pharmacology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Sebastian Schoenherr
- Institute of Genetic Epidemiology, Department of Genetics and Pharmacology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| |
Collapse
|
9
|
Diroma MA, Varvara AS, Attimonelli M, Pesole G, Picardi E. Investigating Human Mitochondrial Genomes in Single Cells. Genes (Basel) 2020; 11:genes11050534. [PMID: 32403285 PMCID: PMC7290567 DOI: 10.3390/genes11050534] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 05/07/2020] [Accepted: 05/08/2020] [Indexed: 12/18/2022] Open
Abstract
Mitochondria host multiple copies of their own small circular genome that has been extensively studied to trace the evolution of the modern eukaryotic cell and discover important mutations linked to inherited diseases. Whole genome and exome sequencing have enabled the study of mtDNA in a large number of samples and experimental conditions at single nucleotide resolution, allowing the deciphering of the relationship between inherited mutations and phenotypes and the identification of acquired mtDNA mutations in classical mitochondrial diseases as well as in chronic disorders, ageing and cancer. By applying an ad hoc computational pipeline based on our MToolBox software, we reconstructed mtDNA genomes in single cells using whole genome and exome sequencing data obtained by different amplification methodologies (eWGA, DOP-PCR, MALBAC, MDA) as well as data from single cell Assay for Transposase Accessible Chromatin with high-throughput sequencing (scATAC-seq) in which mtDNA sequences are expected as a byproduct of the technology. We show that assembled mtDNAs, with the exception of those reconstructed by MALBAC and DOP-PCR methods, are quite uniform and suitable for genomic investigations, enabling the study of various biological processes related to cellular heterogeneity such as tumor evolution, neural somatic mosaicism and embryonic development.
Collapse
Affiliation(s)
- Maria Angela Diroma
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), National Research Council, Via Giovanni Amendola 118, 70126 Bari, Italy; (M.A.D.); (G.P.)
| | - Angelo Sante Varvara
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari “A. Moro”, Via Orabona 4, 70125 Bari, Italy; (A.S.V.); (M.A.)
| | - Marcella Attimonelli
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari “A. Moro”, Via Orabona 4, 70125 Bari, Italy; (A.S.V.); (M.A.)
| | - Graziano Pesole
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), National Research Council, Via Giovanni Amendola 118, 70126 Bari, Italy; (M.A.D.); (G.P.)
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari “A. Moro”, Via Orabona 4, 70125 Bari, Italy; (A.S.V.); (M.A.)
| | - Ernesto Picardi
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), National Research Council, Via Giovanni Amendola 118, 70126 Bari, Italy; (M.A.D.); (G.P.)
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari “A. Moro”, Via Orabona 4, 70125 Bari, Italy; (A.S.V.); (M.A.)
- Correspondence: ; Tel.: +39-0805442179
| |
Collapse
|
10
|
McElhoe JA, Holland MM. Characterization of background noise in MiSeq MPS data when sequencing human mitochondrial DNA from various sample sources and library preparation methods. Mitochondrion 2020; 52:40-55. [PMID: 32068127 DOI: 10.1016/j.mito.2020.02.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 12/18/2019] [Accepted: 02/12/2020] [Indexed: 12/20/2022]
Abstract
Improved resolution of massively parallel sequencing (MPS) allows for the characterization of mitochondrial (mt) DNA heteroplasmy to levels previously unattainable with traditional sequencing approaches. An essential criterion for the reporting of heteroplasmy is the ability of the MPS method to distinguish minor sequence variants (MSVs) from system noise, or error. Therefore, an assessment of the background noise in the MPS method is desirable to identify the point at which reliable data can be reported. Substitution and sequence specific error (SSE) was evaluated for a variety of sample types and two library preparations. Substitution error rates ranged from 0.18 to 0.49 per 100 nucleotides with C positions generally having the highest rate of misincorporation. Comparison of error rates across sample types indicated a significant increase for samples with damaged DNA. The positions of error were varied across datasets (pairwise concordance 0-68%), but had greater consistency within the damaged samples (80-96%). The most commonly observed motif preceding error in forward reads was CCG, while GGT was most common in reverse reads, both consistent with previous findings. The findings illustrate that for datasets containing samples with damaged DNA, reporting thresholds for heteroplasmy may have to be modified and individual sites with error levels exceeding thresholds should be scrutinized. Collectively, the shifting error profiles observed across the various sample types and library preparation methods demonstrates the need for an assessment of error under these varying circumstances. Characterization of the applicable background noise will help to ensure that thresholds are reliably set for detection of true MSVs.
Collapse
Affiliation(s)
- Jennifer A McElhoe
- Department of Biochemistry & Molecular Biology, Forensic Science Program, The Pennsylvania State University, University Park, PA 16802, USA.
| | - Mitchell M Holland
- Department of Biochemistry & Molecular Biology, Forensic Science Program, The Pennsylvania State University, University Park, PA 16802, USA
| |
Collapse
|
11
|
Sensitivity of mitochondrial DNA heteroplasmy detection using Next Generation Sequencing. Mitochondrion 2020; 50:88-93. [DOI: 10.1016/j.mito.2019.10.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 10/10/2019] [Indexed: 01/03/2023]
|
12
|
Huang Y, Lu W, Ji J, Zhang X, Zhang P, Chen W. Heteroplasmy in the complete chicken mitochondrial genome. PLoS One 2019; 14:e0224677. [PMID: 31703075 PMCID: PMC6839896 DOI: 10.1371/journal.pone.0224677] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 10/19/2019] [Indexed: 12/16/2022] Open
Abstract
Chicken mitochondrial DNA is a circular molecule comprising ~16.8 kb. In this study, we used next-generation sequencing to investigate mitochondrial heteroplasmy in the whole chicken mitochondrial genome. Based on heteroplasmic detection thresholds at the 0.5% level, 178 cases of heteroplasmy were identified in the chicken mitochondrial genome, where 83% were due to nucleotide transitions. D-loop regionwas hot spot region for mtDNA heteroplasmy in the chicken since 130 cases of heteroplasmy were located in these regions. Heteroplasmy varied among intraindividual tissues with allele-specific, position-specific, and tissue-specific features. Skeletal muscle had the highest abundance of heteroplasmy. Cases of heteroplasmy at mt.G8682A and mt.G16121A were validated by PCR-restriction fragment length polymorphism analysis, which showed that both had low ratios of heteroplasmy occurrence in five natural breeds. Polymorphic sites were easy to distinguish. Based on NGS data for crureus tissues, mitochondrial mutation/heteroplasmy exhibited clear maternal inheritance features at the whole mitochondrial genomic level. Further investigations of the heterogeneity of the mt.A5694T and mt.T5718G transitions between generations using pyrosequencing based on pedigree information indicated that the degree of heteroplasmy and the occurrence ratio of heteroplasmy decreased greatly from the F0 to F1 generations in the mt.A5694T and mt.T5718G site. Thus, the intergenerational transmission of heteroplasmy in chicken mtDNA exhibited a rapid shift toward homoplasmy within a single generation. Our findings indicate that heteroplasmy is a widespread phenomenon in chicken mitochondrial genome, in which most sites exhibit low heteroplasmy and the allele frequency at heteroplasmic sites changes significantly during transmission events. It suggests that heteroplasmy may be under negative selection to some degree in the chicken.
Collapse
Affiliation(s)
- Yanqun Huang
- College of Livestock Husbandry and Veterinary Engineering, Henan Agricultural University, Zhengzhou, Henan, China
| | - Weiwei Lu
- College of Livestock Husbandry and Veterinary Engineering, Henan Agricultural University, Zhengzhou, Henan, China
| | - Jiefei Ji
- College of Livestock Husbandry and Veterinary Engineering, Henan Agricultural University, Zhengzhou, Henan, China
| | - Xiangli Zhang
- College of Livestock Husbandry and Veterinary Engineering, Henan Agricultural University, Zhengzhou, Henan, China
| | - Pengfei Zhang
- College of Livestock Husbandry and Veterinary Engineering, Henan Agricultural University, Zhengzhou, Henan, China
| | - Wen Chen
- College of Livestock Husbandry and Veterinary Engineering, Henan Agricultural University, Zhengzhou, Henan, China
- * E-mail:
| |
Collapse
|
13
|
Shtolz N, Mishmar D. The Mitochondrial Genome–on Selective Constraints and Signatures at the Organism, Cell, and Single Mitochondrion Levels. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00342] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
|
14
|
Zascavage RR, Thorson K, Planz JV. Nanopore sequencing: An enrichment-free alternative to mitochondrial DNA sequencing. Electrophoresis 2019; 40:272-280. [PMID: 30511783 PMCID: PMC6590251 DOI: 10.1002/elps.201800083] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 10/25/2018] [Accepted: 11/03/2018] [Indexed: 12/31/2022]
Abstract
Mitochondrial DNA sequence data are often utilized in disease studies, conservation genetics and forensic identification. The current approaches for sequencing the full mtGenome typically require several rounds of PCR enrichment during Sanger or MPS protocols followed by fairly tedious assembly and analysis. Here we describe an efficient approach to sequencing directly from genomic DNA samples without prior enrichment or extensive library preparation steps. A comparison is made between libraries sequenced directly from native DNA and the same samples sequenced from libraries generated with nine overlapping mtDNA amplicons on the Oxford Nanopore MinION™ device. The native and amplicon library preparation methods and alternative base calling strategies were assessed to establish error rates and identify trends of discordance between the two library preparation approaches. For the complete mtGenome, 16 569 nucleotides, an overall error rate of approximately 1.00% was observed. As expected with mtDNA, the majority of error was detected in homopolymeric regions. The use of a modified basecaller that corrects for ambiguous signal in homopolymeric stretches reduced the error rate for both library preparation methods to approximately 0.30%. Our study indicates that direct mtDNA sequencing from native DNA on the MinION™ device provides comparable results to those obtained from common mtDNA sequencing methods and is a reliable alternative to approaches using PCR-enriched libraries.
Collapse
Affiliation(s)
- Roxanne R. Zascavage
- Department of MicrobiologyImmunology and GeneticsUniversity of North Texas Health Science CenterFort WorthTXUSA
- Department of Criminology and Criminal JusticeUniversity of Texas at ArlingtonArlingtonTXUSA
| | - Kelcie Thorson
- Department of MicrobiologyImmunology and GeneticsUniversity of North Texas Health Science CenterFort WorthTXUSA
- Zoetis Inc.ParsippanyNJUSA
| | - John V. Planz
- Department of MicrobiologyImmunology and GeneticsUniversity of North Texas Health Science CenterFort WorthTXUSA
| |
Collapse
|
15
|
Hedberg A, Knutsen E, Løvhaugen AS, Jørgensen TE, Perander M, Johansen SD. Cancer-specific SNPs originate from low-level heteroplasmic variants in human mitochondrial genomes of a matched cell line pair. Mitochondrial DNA A DNA Mapp Seq Anal 2018; 30:82-91. [PMID: 29671673 DOI: 10.1080/24701394.2018.1461852] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Low-level mitochondrial heteroplasmy is a common phenomenon in both normal and cancer cells. Here, we investigate the link between low-level heteroplasmy and mitogenome mutations in a human breast cancer matched cell line by high-throughput sequencing. We identified 23 heteroplasmic sites, of which 15 were common between normal cells (Hs578Bst) and cancer cells (Hs578T). Most sites were clustered within the highly conserved Complex IV and ribosomal RNA genes. Two heteroplasmic variants in normal cells were found as fixed mutations in cancer cells. This indicates a positive selection of these variants in cancer cells. RNA-Seq analysis identified upregulated L-strand specific transcripts in cancer cells, which include three mitochondrial long non-coding RNA molecules. We hypothesize that this is due to two cancer cell-specific mutations in the control region.
Collapse
Affiliation(s)
- Annica Hedberg
- a Department of Medical Biology, Faculty of Health Sciences , UiT - The Arctic University of Norway , Tromsø , Norway
| | - Erik Knutsen
- a Department of Medical Biology, Faculty of Health Sciences , UiT - The Arctic University of Norway , Tromsø , Norway
| | - Anne Silje Løvhaugen
- a Department of Medical Biology, Faculty of Health Sciences , UiT - The Arctic University of Norway , Tromsø , Norway
| | - Tor Erik Jørgensen
- b Genomics Group, Faculty of Biosciences and Aquaculture , Nord University , Bodø , Norway
| | - Maria Perander
- a Department of Medical Biology, Faculty of Health Sciences , UiT - The Arctic University of Norway , Tromsø , Norway
| | - Steinar D Johansen
- a Department of Medical Biology, Faculty of Health Sciences , UiT - The Arctic University of Norway , Tromsø , Norway.,b Genomics Group, Faculty of Biosciences and Aquaculture , Nord University , Bodø , Norway
| |
Collapse
|
16
|
Deep-Coverage MPS Analysis of Heteroplasmic Variants within the mtGenome Allows for Frequent Differentiation of Maternal Relatives. Genes (Basel) 2018; 9:genes9030124. [PMID: 29495418 PMCID: PMC5867845 DOI: 10.3390/genes9030124] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2018] [Revised: 02/15/2018] [Accepted: 02/20/2018] [Indexed: 12/11/2022] Open
Abstract
Distinguishing between maternal relatives through mitochondrial (mt) DNA sequence analysis has been a longstanding desire of the forensic community. Using a deep-coverage, massively parallel sequencing (DCMPS) approach, we studied the pattern of mtDNA heteroplasmy across the mtgenomes of 39 mother-child pairs of European decent; haplogroups H, J, K, R, T, U, and X. Both shared and differentiating heteroplasmy were observed on a frequent basis in these closely related maternal relatives, with the minor variant often presented as 2–10% of the sequencing reads. A total of 17 pairs exhibited differentiating heteroplasmy (44%), with the majority of sites (76%, 16 of 21) occurring in the coding region, further illustrating the value of conducting sequence analysis on the entire mtgenome. A number of the sites of differentiating heteroplasmy resulted in non-synonymous changes in protein sequence (5 of 21), and to changes in transfer or ribosomal RNA sequences (5 of 21), highlighting the potentially deleterious nature of these heteroplasmic states. Shared heteroplasmy was observed in 12 of the 39 mother-child pairs (31%), with no duplicate sites of either differentiating or shared heteroplasmy observed; a single nucleotide position (16093) was duplicated between the data sets. Finally, rates of heteroplasmy in blood and buccal cells were compared, as it is known that rates can vary across tissue types, with similar observations in the current study. Our data support the view that differentiating heteroplasmy across the mtgenome can be used to frequently distinguish maternal relatives, and could be of interest to both the medical genetics and forensic communities.
Collapse
|
17
|
Dunn P, Albury CL, Maksemous N, Benton MC, Sutherland HG, Smith RA, Haupt LM, Griffiths LR. Next Generation Sequencing Methods for Diagnosis of Epilepsy Syndromes. Front Genet 2018; 9:20. [PMID: 29467791 PMCID: PMC5808353 DOI: 10.3389/fgene.2018.00020] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 01/16/2018] [Indexed: 12/28/2022] Open
Abstract
Epilepsy is a neurological disorder characterized by an increased predisposition for seizures. Although this definition suggests that it is a single disorder, epilepsy encompasses a group of disorders with diverse aetiologies and outcomes. A genetic basis for epilepsy syndromes has been postulated for several decades, with several mutations in specific genes identified that have increased our understanding of the genetic influence on epilepsies. With 70-80% of epilepsy cases identified to have a genetic cause, there are now hundreds of genes identified to be associated with epilepsy syndromes which can be analyzed using next generation sequencing (NGS) techniques such as targeted gene panels, whole exome sequencing (WES) and whole genome sequencing (WGS). For effective use of these methodologies, diagnostic laboratories and clinicians require information on the relevant workflows including analysis and sequencing depth to understand the specific clinical application and diagnostic capabilities of these gene sequencing techniques. As epilepsy is a complex disorder, the differences associated with each technique influence the ability to form a diagnosis along with an accurate detection of the genetic etiology of the disorder. In addition, for diagnostic testing, an important parameter is the cost-effectiveness and the specific diagnostic outcome of each technique. Here, we review these commonly used NGS techniques to determine their suitability for application to epilepsy genetic diagnostic testing.
Collapse
Affiliation(s)
- Paul Dunn
- Genomics Research Centre, School of Biomedical Sciences, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| | - Cassie L Albury
- Genomics Research Centre, School of Biomedical Sciences, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| | - Neven Maksemous
- Genomics Research Centre, School of Biomedical Sciences, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| | - Miles C Benton
- Genomics Research Centre, School of Biomedical Sciences, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| | - Heidi G Sutherland
- Genomics Research Centre, School of Biomedical Sciences, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| | - Robert A Smith
- Genomics Research Centre, School of Biomedical Sciences, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| | - Larisa M Haupt
- Genomics Research Centre, School of Biomedical Sciences, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| | - Lyn R Griffiths
- Genomics Research Centre, School of Biomedical Sciences, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
| |
Collapse
|
18
|
Peck MA, Sturk-Andreaggi K, Thomas JT, Oliver RS, Barritt-Ross S, Marshall C. Developmental validation of a Nextera XT mitogenome Illumina MiSeq sequencing method for high-quality samples. Forensic Sci Int Genet 2018; 34:25-36. [PMID: 29413633 DOI: 10.1016/j.fsigen.2018.01.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 12/21/2017] [Accepted: 01/12/2018] [Indexed: 12/15/2022]
Abstract
Generating mitochondrial genome (mitogenome) data from reference samples in a rapid and efficient manner is critical to harnessing the greater power of discrimination of the entire mitochondrial DNA (mtDNA) marker. The method of long-range target enrichment, Nextera XT library preparation, and Illumina sequencing on the MiSeq is a well-established technique for generating mitogenome data from high-quality samples. To this end, a validation was conducted for this mitogenome method processing up to 24 samples simultaneously along with analysis in the CLC Genomics Workbench and utilizing the AQME (AFDIL-QIAGEN mtDNA Expert) tool to generate forensic profiles. This validation followed the Federal Bureau of Investigation's Quality Assurance Standards (QAS) for forensic DNA testing laboratories and the Scientific Working Group on DNA Analysis Methods (SWGDAM) validation guidelines. The evaluation of control DNA, non-probative samples, blank controls, mixtures, and nonhuman samples demonstrated the validity of this method. Specifically, the sensitivity was established at ≥25 pg of nuclear DNA input for accurate mitogenome profile generation. Unreproducible low-level variants were observed in samples with low amplicon yields. Further, variant quality was shown to be a useful metric for identifying sequencing error and crosstalk. Success of this method was demonstrated with a variety of reference sample substrates and extract types. These studies further demonstrate the advantages of using NGS techniques by highlighting the quantitative nature of heteroplasmy detection. The results presented herein from more than 175 samples processed in ten sequencing runs, show this mitogenome sequencing method and analysis strategy to be valid for the generation of reference data.
Collapse
Affiliation(s)
- Michelle A Peck
- Armed Forces Medical Examiner System's Armed Forces DNA Identification Laboratory (AFMES-AFDIL), 115 Purple Heart Drive, Dover AFB, DE, 19902, United States; ARP Sciences, LLC, Contractor Supporting the Armed Forces Medical Examiner System, 9210 Corporate Boulevard, Suite 120, Rockville, MD, 20850, United States
| | - Kimberly Sturk-Andreaggi
- Armed Forces Medical Examiner System's Armed Forces DNA Identification Laboratory (AFMES-AFDIL), 115 Purple Heart Drive, Dover AFB, DE, 19902, United States; ARP Sciences, LLC, Contractor Supporting the Armed Forces Medical Examiner System, 9210 Corporate Boulevard, Suite 120, Rockville, MD, 20850, United States
| | - Jacqueline T Thomas
- Armed Forces Medical Examiner System's Armed Forces DNA Identification Laboratory (AFMES-AFDIL), 115 Purple Heart Drive, Dover AFB, DE, 19902, United States; ARP Sciences, LLC, Contractor Supporting the Armed Forces Medical Examiner System, 9210 Corporate Boulevard, Suite 120, Rockville, MD, 20850, United States
| | - Robert S Oliver
- Armed Forces Medical Examiner System's Armed Forces DNA Identification Laboratory (AFMES-AFDIL), 115 Purple Heart Drive, Dover AFB, DE, 19902, United States; ARP Sciences, LLC, Contractor Supporting the Armed Forces Medical Examiner System, 9210 Corporate Boulevard, Suite 120, Rockville, MD, 20850, United States
| | - Suzanne Barritt-Ross
- Armed Forces Medical Examiner System's Armed Forces DNA Identification Laboratory (AFMES-AFDIL), 115 Purple Heart Drive, Dover AFB, DE, 19902, United States; ARP Sciences, LLC, Contractor Supporting the Armed Forces Medical Examiner System, 9210 Corporate Boulevard, Suite 120, Rockville, MD, 20850, United States
| | - Charla Marshall
- Armed Forces Medical Examiner System's Armed Forces DNA Identification Laboratory (AFMES-AFDIL), 115 Purple Heart Drive, Dover AFB, DE, 19902, United States; ARP Sciences, LLC, Contractor Supporting the Armed Forces Medical Examiner System, 9210 Corporate Boulevard, Suite 120, Rockville, MD, 20850, United States.
| |
Collapse
|
19
|
Massive parallel sequencing of mitochondrial DNA genomes from mother-child pairs using the ion torrent personal genome machine (PGM). Forensic Sci Int Genet 2018; 32:88-93. [DOI: 10.1016/j.fsigen.2017.11.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 09/26/2017] [Accepted: 11/05/2017] [Indexed: 11/15/2022]
|
20
|
Genome sequence and analysis of Escherichia coli production strain LS5218. Metab Eng Commun 2017; 5:78-83. [PMID: 29188187 PMCID: PMC5699524 DOI: 10.1016/j.meteno.2017.10.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 09/29/2017] [Accepted: 10/31/2017] [Indexed: 01/06/2023] Open
Abstract
Escherichia coli strain LS5218 is a useful host for the production of fatty acid derived products, but the genetics underlying this utility have not been fully investigated. Here, we report the genome sequence of LS5218 and a list of large mutations and single nucleotide permutations (SNPs) relative to E. coli K-12 strain MG1655. We discuss how genetic differences may affect the physiological differences between LS5218 and MG1655. We find that LS5218 is more closely related to E. coli strain NCM3722 and suspect that small genetic differences between K-12 derived strains may have a significant impact on metabolic engineering efforts.
Collapse
|
21
|
Ostersetzer-Biran O, Lane N, Pomiankowski A, Burton R, Arnqvist G, Filipovska A, Huchon D, Mishmar D. The First Mitochondrial Genomics and Evolution SMBE-Satellite Meeting: A New Scientific Symbiosis. Genome Biol Evol 2017; 9:3054-3058. [PMID: 29106528 PMCID: PMC5714122 DOI: 10.1093/gbe/evx227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/01/2017] [Indexed: 11/12/2022] Open
Abstract
The central role of the mitochondrion for cellular and organismal metabolism is well known, yet its functional role in evolution has rarely been featured in leading international conferences. Moreover, the contribution of mitochondrial genetics to complex disease phenotypes is particularly important, and although major advances have been made in the field of genomics, mitochondrial genomic data have in many cases been overlooked. Accumulating data and new knowledge support a major contribution of this maternally inherited genome, and its interactions with the nucleus, to both major evolutionary processes and diverse disease phenotypes. These advances encouraged us to assemble the first Mitochondrial Genomics and Evolution (MGE) meeting-an SMBE satellite and Israeli Science foundation international conference (Israel, September 2017). Here, we report the content and outcome of the MGE meeting (https://www.mge2017.com/; last accessed November 5, 2017).
Collapse
Affiliation(s)
| | - Nick Lane
- Department of Genetics, Evolution and Environment, University College London, United Kingdom
| | - Andrew Pomiankowski
- Department of Genetics, Evolution and Environment, University College London, United Kingdom
| | - Ron Burton
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego
| | - Göran Arnqvist
- Department of Ecology and Genetics, University of Uppsala, Sweden
| | - Aleksandra Filipovska
- School of Molecular Sciences and The Harry Perkins Institute of Medical Research, The University of Western Australia, Australia
| | - Dorothée Huchon
- Department of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Israel.,The Steinhardt Museum of Natural History and Israel National Center for Biodiversity Studies, Tel Aviv, Israel
| | - Dan Mishmar
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| |
Collapse
|
22
|
Rand JM, Pisithkul T, Clark RL, Thiede JM, Mehrer CR, Agnew DE, Campbell CE, Markley AL, Price MN, Ray J, Wetmore KM, Suh Y, Arkin AP, Deutschbauer AM, Amador-Noguez D, Pfleger BF. A metabolic pathway for catabolizing levulinic acid in bacteria. Nat Microbiol 2017; 2:1624-1634. [PMID: 28947739 PMCID: PMC5705400 DOI: 10.1038/s41564-017-0028-z] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 08/16/2017] [Indexed: 12/21/2022]
Abstract
Microorganisms can catabolize a wide range of organic compounds and therefore have the potential to perform many industrially relevant bioconversions. One barrier to realizing the potential of biorefining strategies lies in our incomplete knowledge of metabolic pathways, including those that can be used to assimilate naturally abundant or easily generated feedstocks. For instance, levulinic acid (LA) is a carbon source that is readily obtainable as a dehydration product of lignocellulosic biomass and can serve as the sole carbon source for some bacteria. Yet, the genetics and structure of LA catabolism have remained unknown. Here, we report the identification and characterization of a seven-gene operon that enables LA catabolism in Pseudomonas putida KT2440. When the pathway was reconstituted with purified proteins, we observed the formation of four acyl-CoA intermediates, including a unique 4-phosphovaleryl-CoA and the previously observed 3-hydroxyvaleryl-CoA product. Using adaptive evolution, we obtained a mutant of Escherichia coli LS5218 with functional deletions of fadE and atoC that was capable of robust growth on LA when it expressed the five enzymes from the P. putida operon. This discovery will enable more efficient use of biomass hydrolysates and metabolic engineering to develop bioconversions using LA as a feedstock.
Collapse
Affiliation(s)
- Jacqueline M Rand
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Tippapha Pisithkul
- Graduate Program in Cellular and Molecular Biology, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Ryan L Clark
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Joshua M Thiede
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Christopher R Mehrer
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Daniel E Agnew
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Candace E Campbell
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Andrew L Markley
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Morgan N Price
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Jayashree Ray
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Kelly M Wetmore
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Yumi Suh
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Adam P Arkin
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.,Department of Bioengineering, University of California, Berkeley, CA, 94720, USA
| | - Adam M Deutschbauer
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Daniel Amador-Noguez
- Graduate Program in Cellular and Molecular Biology, University of Wisconsin-Madison, Madison, WI, 53706, USA.,Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Brian F Pfleger
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA.
| |
Collapse
|
23
|
Riman S, Kiesler KM, Borsuk LA, Vallone PM. Characterization of NIST human mitochondrial DNA SRM-2392 and SRM-2392-I standard reference materials by next generation sequencing. Forensic Sci Int Genet 2017; 29:181-192. [DOI: 10.1016/j.fsigen.2017.04.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 03/17/2017] [Accepted: 04/04/2017] [Indexed: 12/12/2022]
|
24
|
MitoRS, a method for high throughput, sensitive, and accurate detection of mitochondrial DNA heteroplasmy. BMC Genomics 2017; 18:326. [PMID: 28441938 PMCID: PMC5405551 DOI: 10.1186/s12864-017-3695-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 04/10/2017] [Indexed: 01/23/2023] Open
Abstract
Background Mitochondrial dysfunction is linked to numerous pathological states, in particular related to metabolism, brain health and ageing. Nuclear encoded gene polymorphisms implicated in mitochondrial functions can be analyzed in the context of classical genome wide association studies. By contrast, mitochondrial DNA (mtDNA) variants are more challenging to identify and analyze for several reasons. First, contrary to the diploid nuclear genome, each cell carries several hundred copies of the circular mitochondrial genome. Mutations can therefore be present in only a subset of the mtDNA molecules, resulting in a heterogeneous pool of mtDNA, a situation referred to as heteroplasmy. Consequently, detection and quantification of variants requires extremely accurate tools, especially when this proportion is small. Additionally, the mitochondrial genome has pseudogenized into numerous copies within the nuclear genome over the course of evolution. These nuclear pseudogenes, named NUMTs, must be distinguished from genuine mtDNA sequences and excluded from the analysis. Results Here we describe a novel method, named MitoRS, in which the entire mitochondrial genome is amplified in a single reaction using rolling circle amplification. This approach is easier to setup and of higher throughput when compared to classical PCR amplification. Sequencing libraries are generated at high throughput exploiting a tagmentation-based method. Fine-tuned parameters are finally applied in the analysis to allow detection of variants even of low frequency heteroplasmy. The method was thoroughly benchmarked in a set of experiments designed to demonstrate its robustness, accuracy and sensitivity. The MitoRS method requires 5 ng total DNA as starting material. More than 96 samples can be processed in less than a day of laboratory work and sequenced in a single lane of an Illumina HiSeq flow cell. The lower limit for accurate quantification of single nucleotide variants has been measured at 1% frequency. Conclusions The MitoRS method enables the robust, accurate, and sensitive analysis of a large number of samples. Because it is cost effective and simple to setup, we anticipate this method will promote the analysis of mtDNA variants in large cohorts, and may help assessing the impact of mtDNA heteroplasmy on metabolic health, brain function, cancer progression, or ageing. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3695-5) contains supplementary material, which is available to authorized users.
Collapse
|
25
|
Errichiello E, Venesio T. Mitochondrial DNA variants in colorectal carcinogenesis: Drivers or passengers? J Cancer Res Clin Oncol 2017; 143:1905-1914. [PMID: 28393270 DOI: 10.1007/s00432-017-2418-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 04/03/2017] [Indexed: 12/22/2022]
Abstract
INTRODUCTION Mitochondrial DNA alterations have widely been reported in many age-related degenerative diseases and tumors, including colorectal cancer. In the past few years, the discovery of inter-genomic crosstalk between nucleus and mitochondria has reinforced the role of mitochondrial DNA variants in perturbing this essential signaling pathway and thus indirectly targeting nuclear genes involved in tumorigenic and invasive phenotype. FINDINGS Mitochondrial dysfunction is currently considered a crucial hallmark of carcinogenesis as well as a promising target for anticancer therapy. Mitochondrial DNA alterations include point mutations, deletions, inversions, and copy number variations, but numerous studies investigating their pathogenic role in cancer have provided inconsistent evidence. Furthermore, the biological impact of mitochondrial DNA variants may vary tremendously, depending on the proportion of mutant DNA molecules carried by the neoplastic cells (heteroplasmy). CONCLUSIONS In this review, we discuss the role of different type of mitochondrial DNA alterations in colorectal carcinogenesis and, in particular, we revisit the issue of whether they may be considered as causative driver or simply genuine passenger events. The advent of high-throughput techniques as well as the development of genetic and pharmaceutical interventions for the treatment of mitochondrial dysfunction in colorectal cancer are also explored.
Collapse
Affiliation(s)
- Edoardo Errichiello
- Department of Molecular Medicine, University of Pavia, Via Forlanini 14, 27100, Pavia, Italy.
- Molecular Pathology Laboratory, Unit of Pathology, Candiolo Cancer Institute, FPO-IRCCS, Starda Provinciale 142, Candiolo, 10060, Turin, Italy.
| | - Tiziana Venesio
- Molecular Pathology Laboratory, Unit of Pathology, Candiolo Cancer Institute, FPO-IRCCS, Starda Provinciale 142, Candiolo, 10060, Turin, Italy
| |
Collapse
|
26
|
Patterns of cross-contamination in a multispecies population genomic project: detection, quantification, impact, and solutions. BMC Biol 2017; 15:25. [PMID: 28356154 PMCID: PMC5370491 DOI: 10.1186/s12915-017-0366-6] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 03/13/2017] [Indexed: 01/06/2023] Open
Abstract
Background Contamination is a well-known but often neglected problem in molecular biology. Here, we investigated the prevalence of cross-contamination among 446 samples from 116 distinct species of animals, which were processed in the same laboratory and subjected to subcontracted transcriptome sequencing. Results Using cytochrome oxidase 1 as a barcode, we identified a minimum of 782 events of between-species contamination, with approximately 80% of our samples being affected. An analysis of laboratory metadata revealed a strong effect of the sequencing center: nearly all the detected events of between-species contamination involved species that were sent the same day to the same company. We introduce new methods to address the amount of within-species, between-individual contamination, and to correct for this problem when calling genotypes from base read counts. Conclusions We report evidence for pervasive within-species contamination in this data set, and show that classical population genomic statistics, such as synonymous diversity, the ratio of non-synonymous to synonymous diversity, inbreeding coefficient FIT, and Tajima’s D, are sensitive to this problem to various extents. Control analyses suggest that our published results are probably robust to the problem of contamination. Recommendations on how to prevent or avoid contamination in large-scale population genomics/molecular ecology are provided based on this analysis. Electronic supplementary material The online version of this article (doi:10.1186/s12915-017-0366-6) contains supplementary material, which is available to authorized users.
Collapse
|
27
|
Albayrak L, Khanipov K, Pimenova M, Golovko G, Rojas M, Pavlidis I, Chumakov S, Aguilar G, Chávez A, Widger WR, Fofanov Y. The ability of human nuclear DNA to cause false positive low-abundance heteroplasmy calls varies across the mitochondrial genome. BMC Genomics 2016; 17:1017. [PMID: 27955616 PMCID: PMC5153897 DOI: 10.1186/s12864-016-3375-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 12/05/2016] [Indexed: 02/03/2023] Open
Abstract
Background Low-abundance mutations in mitochondrial populations (mutations with minor allele frequency ≤ 1%), are associated with cancer, aging, and neurodegenerative disorders. While recent progress in high-throughput sequencing technology has significantly improved the heteroplasmy identification process, the ability of this technology to detect low-abundance mutations can be affected by the presence of similar sequences originating from nuclear DNA (nDNA). To determine to what extent nDNA can cause false positive low-abundance heteroplasmy calls, we have identified mitochondrial locations of all subsequences that are common or similar (one mismatch allowed) between nDNA and mitochondrial DNA (mtDNA). Results Performed analysis revealed up to a 25-fold variation in the lengths of longest common and longest similar (one mismatch allowed) subsequences across the mitochondrial genome. The size of the longest subsequences shared between nDNA and mtDNA in several regions of the mitochondrial genome were found to be as low as 11 bases, which not only allows using these regions to design new, very specific PCR primers, but also supports the hypothesis of the non-random introduction of mtDNA into the human nuclear DNA. Conclusion Analysis of the mitochondrial locations of the subsequences shared between nDNA and mtDNA suggested that even very short (36 bases) single-end sequencing reads can be used to identify low-abundance variation in 20.4% of the mitochondrial genome. For longer (76 and 150 bases) reads, the proportion of the mitochondrial genome where nDNA presence will not interfere found to be 44.5 and 67.9%, when low-abundance mutations at 100% of locations can be identified using 417 bases long single reads. This observation suggests that the analysis of low-abundance variations in mitochondria population can be extended to a variety of large data collections such as NCBI Sequence Read Archive, European Nucleotide Archive, The Cancer Genome Atlas, and International Cancer Genome Consortium. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3375-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Levent Albayrak
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555-0144, USA.,Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, USA.,Department of Computer Science, University of Houston, Houston, TX, USA
| | - Kamil Khanipov
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555-0144, USA.,Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, USA.,Department of Computer Science, University of Houston, Houston, TX, USA
| | - Maria Pimenova
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555-0144, USA.,Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, USA
| | - George Golovko
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555-0144, USA.,Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, USA
| | - Mark Rojas
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555-0144, USA.,Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, USA
| | - Ioannis Pavlidis
- Department of Computer Science, University of Houston, Houston, TX, USA
| | - Sergei Chumakov
- Department of Physics, University of Guadalajara, Guadalajara, Jalisco, Mexico
| | - Gerardo Aguilar
- Department of Physics, University of Guadalajara, Guadalajara, Jalisco, Mexico
| | - Arturo Chávez
- Department of Physics, University of Guadalajara, Guadalajara, Jalisco, Mexico
| | - William R Widger
- Department of Biology and Biochemistry, University of Houston, Houston, TX, USA
| | - Yuriy Fofanov
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX, 77555-0144, USA. .,Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, USA.
| |
Collapse
|
28
|
Wang Y, Picard M, Gu Z. Genetic Evidence for Elevated Pathogenicity of Mitochondrial DNA Heteroplasmy in Autism Spectrum Disorder. PLoS Genet 2016; 12:e1006391. [PMID: 27792786 PMCID: PMC5085253 DOI: 10.1371/journal.pgen.1006391] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Accepted: 09/28/2016] [Indexed: 01/07/2023] Open
Abstract
Increasing clinical and biochemical evidence implicate mitochondrial dysfunction in the pathophysiology of Autism Spectrum Disorder (ASD), but little is known about the biological basis for this connection. A possible cause of ASD is the genetic variation in the mitochondrial DNA (mtDNA) sequence, which has yet to be thoroughly investigated in large genomic studies of ASD. Here we evaluated mtDNA variation, including the mixture of different mtDNA molecules in the same individual (i.e., heteroplasmy), using whole-exome sequencing data from mother-proband-sibling trios from simplex families (n = 903) where only one child is affected by ASD. We found that heteroplasmic mutations in autistic probands were enriched at non-polymorphic mtDNA sites (P = 0.0015), which were more likely to confer deleterious effects than heteroplasmies at polymorphic mtDNA sites. Accordingly, we observed a ~1.5-fold enrichment of nonsynonymous mutations (P = 0.0028) as well as a ~2.2-fold enrichment of predicted pathogenic mutations (P = 0.0016) in autistic probands compared to their non-autistic siblings. Both nonsynonymous and predicted pathogenic mutations private to probands conferred increased risk of ASD (Odds Ratio, OR[95% CI] = 1.87[1.14-3.11] and 2.55[1.26-5.51], respectively), and their influence on ASD was most pronounced in families with probands showing diminished IQ and/or impaired social behavior compared to their non-autistic siblings. We also showed that the genetic transmission pattern of mtDNA heteroplasmies with high pathogenic potential differed between mother-autistic proband pairs and mother-sibling pairs, implicating developmental and possibly in utero contributions. Taken together, our genetic findings substantiate pathogenic mtDNA mutations as a potential cause for ASD and synergize with recent work calling attention to their unique metabolic phenotypes for diagnosis and treatment of children with ASD.
Collapse
Affiliation(s)
- Yiqin Wang
- Division of Nutritional Sciences, Cornell University, Ithaca, New York, United States of America
| | - Martin Picard
- Department of Psychiatry, Division of Behavioral Medicine, Columbia University Medical Center, New York, New York, United States of America
- Department of Neurology, Division of Columbia Translational Neuroscience Initiative, Columbia University Medical Center, New York, New York, United States of America
| | - Zhenglong Gu
- Division of Nutritional Sciences, Cornell University, Ithaca, New York, United States of America
| |
Collapse
|
29
|
Stoler N, Arbeithuber B, Guiblet W, Makova KD, Nekrutenko A. Streamlined analysis of duplex sequencing data with Du Novo. Genome Biol 2016; 17:180. [PMID: 27566673 PMCID: PMC5000403 DOI: 10.1186/s13059-016-1039-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 08/05/2016] [Indexed: 11/16/2022] Open
Abstract
Duplex sequencing was originally developed to detect rare nucleotide polymorphisms normally obscured by the noise of high-throughput sequencing. Here we describe a new, streamlined, reference-free approach for the analysis of duplex sequencing data. We show the approach performs well on simulated data and precisely reproduces previously published results and apply it to a newly produced dataset, enabling us to type low-frequency variants in human mitochondrial DNA. Finally, we provide all necessary tools as stand-alone components as well as integrate them into the Galaxy platform. All analyses performed in this manuscript can be repeated exactly as described at http://usegalaxy.org/duplex .
Collapse
Affiliation(s)
- Nicholas Stoler
- Graduate Program in Bioinformatics and Genomics, The Huck Institutes for the Life Sciences, Penn State University, 505 Wartik Lab, University Park, PA, 16802, USA
| | | | - Wilfried Guiblet
- Graduate Program in Bioinformatics and Genomics, The Huck Institutes for the Life Sciences, Penn State University, 505 Wartik Lab, University Park, PA, 16802, USA
| | - Kateryna D Makova
- Department of Biology, Penn State University, 310 Wartik Lab, University Park, PA, 16802, USA.
| | - Anton Nekrutenko
- Graduate Program in Bioinformatics and Genomics, The Huck Institutes for the Life Sciences, Penn State University, 505 Wartik Lab, University Park, PA, 16802, USA.
- Department of Biochemistry and Molecular Biology, Penn State University, University Park, PA, USA.
| |
Collapse
|
30
|
Rensch T, Villar D, Horvath J, Odom DT, Flicek P. Mitochondrial heteroplasmy in vertebrates using ChIP-sequencing data. Genome Biol 2016; 17:139. [PMID: 27349964 PMCID: PMC4922064 DOI: 10.1186/s13059-016-0996-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 06/03/2016] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Mitochondrial heteroplasmy, the presence of more than one mitochondrial DNA (mtDNA) variant in a cell or individual, is not as uncommon as previously thought. It is mostly due to the high mutation rate of the mtDNA and limited repair mechanisms present in the mitochondrion. Motivated by mitochondrial diseases, much focus has been placed into studying this phenomenon in human samples and in medical contexts. To place these results in an evolutionary context and to explore general principles of heteroplasmy, we describe an integrated cross-species evaluation of heteroplasmy in mammals that exploits previously reported NGS data. Focusing on ChIP-seq experiments, we developed a novel approach to detect heteroplasmy from the concomitant mitochondrial DNA fraction sequenced in these experiments. RESULTS We first demonstrate that the sequencing coverage of mtDNA in ChIP-seq experiments is sufficient for heteroplasmy detection. We then describe a novel detection method for accurate detection of heteroplasmies, which also accounts for the error rate of NGS technology. Applying this method to 79 individuals from 16 species resulted in 107 heteroplasmic positions present in a total of 45 individuals. Further analysis revealed that the majority of detected heteroplasmies occur in intergenic regions. CONCLUSION In addition to documenting the prevalence of mtDNA in ChIP-seq data, the results of our mitochondrial heteroplasmy detection method suggest that mitochondrial heteroplasmies identified across vertebrates share similar characteristics as found for human heteroplasmies. Although largely consistent with previous studies in individual vertebrates, our integrated cross-species analysis provides valuable insights into the evolutionary dynamics of mitochondrial heteroplasmy.
Collapse
Affiliation(s)
- Thomas Rensch
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SD, UK
| | - Diego Villar
- Cancer Research UK Cambridge Institute, University of Cambridge, Robinson Way, Cambridge, CB2 0RE, UK
| | - Julie Horvath
- Biological and Biomedical Sciences, North Carolina Central University, Durham, NC, 27707, USA
- North Carolina Museum of Natural Sciences, Raleigh, NC, 27601, USA
| | - Duncan T Odom
- Cancer Research UK Cambridge Institute, University of Cambridge, Robinson Way, Cambridge, CB2 0RE, UK
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, UK
| | - Paul Flicek
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SD, UK.
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, UK.
| |
Collapse
|
31
|
Preston JL, Royall AE, Randel MA, Sikkink KL, Phillips PC, Johnson EA. High-specificity detection of rare alleles with Paired-End Low Error Sequencing (PELE-Seq). BMC Genomics 2016; 17:464. [PMID: 27301885 PMCID: PMC4908710 DOI: 10.1186/s12864-016-2669-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Accepted: 04/25/2016] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Polymorphic loci exist throughout the genomes of a population and provide the raw genetic material needed for a species to adapt to changes in the environment. The minor allele frequencies of rare Single Nucleotide Polymorphisms (SNPs) within a population have been difficult to track with Next-Generation Sequencing (NGS), due to the high error rate of standard methods such as Illumina sequencing. RESULTS We have developed a wet-lab protocol and variant-calling method that identifies both sequencing and PCR errors, called Paired-End Low Error Sequencing (PELE-Seq). To test the specificity and sensitivity of the PELE-Seq method, we sequenced control E. coli DNA libraries containing known rare alleles present at frequencies ranging from 0.2-0.4 % of the total reads. PELE-Seq had higher specificity and sensitivity than standard libraries. We then used PELE-Seq to characterize rare alleles in a Caenorhabditis remanei nematode worm population before and after laboratory adaptation, and found that minor and rare alleles can undergo large changes in frequency during lab-adaptation. CONCLUSION We have developed a method of rare allele detection that mitigates both sequencing and PCR errors, called PELE-Seq. PELE-Seq was evaluated using control E. coli populations and was then used to compare a wild C. remanei population to a lab-adapted population. The PELE-Seq method is ideal for investigating the dynamics of rare alleles in a broad range of reduced-representation sequencing methods, including targeted amplicon sequencing, RAD-Seq, ddRAD, and GBS. PELE-Seq is also well-suited for whole genome sequencing of mitochondria and viruses, and for high-throughput rare mutation screens.
Collapse
Affiliation(s)
- Jessica L Preston
- Institute of Molecular Biology, University of Oregon, Eugene, Oregon, USA.
| | - Ariel E Royall
- Institute of Molecular Biology, University of Oregon, Eugene, Oregon, USA
| | - Melissa A Randel
- Institute of Molecular Biology, University of Oregon, Eugene, Oregon, USA
| | - Kristin L Sikkink
- Institute of Ecology and Evolution, University of Oregon, Eugene, Oregon, USA
| | - Patrick C Phillips
- Institute of Ecology and Evolution, University of Oregon, Eugene, Oregon, USA
| | - Eric A Johnson
- Institute of Molecular Biology, University of Oregon, Eugene, Oregon, USA
| |
Collapse
|
32
|
Ni S, Stoneking M. Improvement in detection of minor alleles in next generation sequencing by base quality recalibration. BMC Genomics 2016; 17:139. [PMID: 26920804 PMCID: PMC4769523 DOI: 10.1186/s12864-016-2463-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 02/11/2016] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Minor allele detection in very high coverage sequence data (>1000X) has many applications such as detecting mtDNA heteroplasmy, somatic mutations in cancer or tumors, SNP calling in pool sequencing, etc., where reads with low frequency are not necessarily sequence error but may instead convey biological information. However, the suitability of common base quality recalibration tools for such applications has not been investigated in detail. RESULTS We show that the widely used tool GATK BaseRecalibration has several limitations in minor allele detection. First, GATK IndelRealignment fails to work if the sequence coverage is above a certain level since it then becomes computationally infeasible. Second, the accuracy of the base quality largely depends on the database of known SNPs as the control, which limits the ability of de novo minor allele detection. Third, GATK reduces the base quality of sequence errors at the cost of reducing scores for true minor alleles. To overcome these limitations, we present a novel approach called SEGREG, which applies segmented regression to control sequences (e.g. phiX174 DNA) spiked into a sequencing run. Based on simulations SEGREG improves both the accuracy of base quality scores and the detection of minor alleles. We further investigate sequence error and recalibration parameters by applying a Logarithm Likelihood Ratio (LLR) approach to SEGREG recalibrated base quality scores for phiX174 DNA sequenced to very high coverage, and for mtDNA genome sequences previously analyzed for heteroplasmic variants. CONCLUSIONS Our results suggest that SEGREG improves base recalibration without suffering the limitations discussed above, and the LLR approach benefits from SEGREG in identifying more true minor alleles, while avoiding false positives from sequencing error.
Collapse
Affiliation(s)
- Shengyu Ni
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Leipzig, D04103, Germany.
| | - Mark Stoneking
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Leipzig, D04103, Germany.
| |
Collapse
|
33
|
Li M, Rothwell R, Vermaat M, Wachsmuth M, Schröder R, Laros JFJ, van Oven M, de Bakker PIW, Bovenberg JA, van Duijn CM, van Ommen GJB, Slagboom PE, Swertz MA, Wijmenga C, Kayser M, Boomsma DI, Zöllner S, de Knijff P, Stoneking M. Transmission of human mtDNA heteroplasmy in the Genome of the Netherlands families: support for a variable-size bottleneck. Genome Res 2016; 26:417-26. [PMID: 26916109 PMCID: PMC4817766 DOI: 10.1101/gr.203216.115] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 01/21/2016] [Indexed: 12/17/2022]
Abstract
Although previous studies have documented a bottleneck in the transmission of mtDNA genomes from mothers to offspring, several aspects remain unclear, including the size and nature of the bottleneck. Here, we analyze the dynamics of mtDNA heteroplasmy transmission in the Genomes of the Netherlands (GoNL) data, which consists of complete mtDNA genome sequences from 228 trios, eight dizygotic (DZ) twin quartets, and 10 monozygotic (MZ) twin quartets. Using a minor allele frequency (MAF) threshold of 2%, we identified 189 heteroplasmies in the trio mothers, of which 59% were transmitted to offspring, and 159 heteroplasmies in the trio offspring, of which 70% were inherited from the mothers. MZ twin pairs exhibited greater similarity in MAF at heteroplasmic sites than DZ twin pairs, suggesting that the heteroplasmy MAF in the oocyte is the major determinant of the heteroplasmy MAF in the offspring. We used a likelihood method to estimate the effective number of mtDNA genomes transmitted to offspring under different bottleneck models; a variable bottleneck size model provided the best fit to the data, with an estimated mean of nine individual mtDNA genomes transmitted. We also found evidence for negative selection during transmission against novel heteroplasmies (in which the minor allele has never been observed in polymorphism data). These novel heteroplasmies are enhanced for tRNA and rRNA genes, and mutations associated with mtDNA diseases frequently occur in these genes. Our results thus suggest that the female germ line is able to recognize and select against deleterious heteroplasmies.
Collapse
Affiliation(s)
- Mingkun Li
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany; Fondation Mérieux, 69002 Lyon, France
| | - Rebecca Rothwell
- Department of Biostatistics and Center for Statistical Genetics, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Martijn Vermaat
- Leiden Genome Technology Center, Department of Human Genetics, Leiden University Medical Center, Leiden 2300 RC, The Netherlands
| | - Manja Wachsmuth
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany
| | - Roland Schröder
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany
| | - Jeroen F J Laros
- Leiden Genome Technology Center, Department of Human Genetics, Leiden University Medical Center, Leiden 2300 RC, The Netherlands
| | - Mannis van Oven
- Department of Genetic Identification, Erasmus MC University Medical Center Rotterdam, Rotterdam 3000 CA, The Netherlands
| | - Paul I W de Bakker
- Department of Medical Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht 3584 CG, The Netherlands; Department of Epidemiology, Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht 3584 CG, The Netherlands
| | - Jasper A Bovenberg
- Department of Biological Psychology, VU University Amsterdam, Amsterdam 1081 BT, The Netherlands
| | - Cornelia M van Duijn
- Legal Pathways Institute for Health and Bio Law, Aerdenhout 2111, The Netherlands
| | - Gert-Jan B van Ommen
- Department of Epidemiology, Erasmus MC University Medical Center Rotterdam, Rotterdam 3000 CA, The Netherlands
| | - P Eline Slagboom
- Department of Human Genetics, Leiden University Medical Center, Leiden 2300 RC, The Netherlands
| | - Morris A Swertz
- Section of Molecular Epidemiology, Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, Leiden 2300 RC, The Netherlands; Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen 9700 RB, The Netherlands
| | - Cisca Wijmenga
- Section of Molecular Epidemiology, Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, Leiden 2300 RC, The Netherlands; Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen 9700 RB, The Netherlands
| | | | - Manfred Kayser
- Department of Genetic Identification, Erasmus MC University Medical Center Rotterdam, Rotterdam 3000 CA, The Netherlands
| | - Dorret I Boomsma
- Genomics Coordination Center, University Medical Center Groningen, University of Groningen, Groningen 9700 RB, The Netherlands
| | - Sebastian Zöllner
- Department of Biostatistics and Center for Statistical Genetics, University of Michigan, Ann Arbor, Michigan 48109, USA; Department of Psychiatry, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Peter de Knijff
- Department of Human Genetics, Leiden University Medical Center, Leiden 2300 RC, The Netherlands
| | - Mark Stoneking
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, 04103 Leipzig, Germany
| |
Collapse
|
34
|
Stefano GB, Kream RM. Mitochondrial DNA heteroplasmy in human health and disease. Biomed Rep 2016; 4:259-262. [PMID: 26998260 PMCID: PMC4774312 DOI: 10.3892/br.2016.590] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 02/02/2016] [Indexed: 12/14/2022] Open
Abstract
The biomedical literature has extensively documented the functional roles of genetic polymorphisms in concert with well-characterized somatic mutations in the etiology and progression of major metastatic diseases afflicting human populations. Mitochondrial heteroplasmy exists as a dynamically determined co-expression of inherited polymorphisms and somatic mutations in varying ratios within individual mitochondrial DNA genomes with repetitive patterns of tissue specificity. Mechanistically, carcinogenic cellular processes include profound alterations of normative mitochondrial function, notably dependence on aerobic and anaerobic glycolysis, and aberrant production and release of lactate, according to a classic theory. Within the translational context of human health and disease, the present review discusses the necessity of establishing critical foci designed to probe multiple biological roles of mitochondrial heteroplasmy in cancer biology.
Collapse
|
35
|
Segregation of Naturally Occurring Mitochondrial DNA Variants in a Mini-Pig Model. Genetics 2016; 202:931-44. [PMID: 26819245 DOI: 10.1534/genetics.115.181321] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 01/17/2016] [Indexed: 11/18/2022] Open
Abstract
The maternally inherited mitochondrial genome (mtDNA) is present in multimeric form within cells and harbors sequence variants (heteroplasmy). While a single mtDNA variant at high load can cause disease, naturally occurring variants likely persist at low levels across generations of healthy populations. To determine how naturally occurring variants are segregated and transmitted, we generated a mini-pig model, which originates from the same maternal ancestor. Following next-generation sequencing, we identified a series of low-level mtDNA variants in blood samples from the female founder and her daughters. Four variants, ranging from 3% to 20%, were selected for validation by high-resolution melting analysis in 12 tissues from 31 animals across three generations. All four variants were maintained in the offspring, but variant load fluctuated significantly across the generations in several tissues, with sex-specific differences in heart and liver. Moreover, variant load was persistently reduced in high-respiratory organs (heart, brain, diaphragm, and muscle), which correlated significantly with higher mtDNA copy number. However, oocytes showed increased heterogeneity in variant load, which correlated with increased mtDNA copy number during in vitro maturation. Altogether, these outcomes show that naturally occurring mtDNA variants segregate and are maintained in a tissue-specific manner across generations. This segregation likely involves the maintenance of selective mtDNA variants during organogenesis, which can be differentially regulated in oocytes and preimplantation embryos during maturation.
Collapse
|
36
|
Billing-Ross P, Germain A, Ye K, Keinan A, Gu Z, Hanson MR. Mitochondrial DNA variants correlate with symptoms in myalgic encephalomyelitis/chronic fatigue syndrome. J Transl Med 2016; 14:19. [PMID: 26791940 PMCID: PMC4719218 DOI: 10.1186/s12967-016-0771-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 01/05/2016] [Indexed: 01/28/2023] Open
Abstract
Background Mitochondrial dysfunction has been hypothesized to occur in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), a disease characterized by fatigue, cognitive difficulties, pain, malaise, and exercise intolerance. We investigated whether haplogroup, single nucleotide polymorphisms (SNPs), or heteroplasmy of mitochondrial DNA (mtDNA) were associated with health status and/or symptoms. Methods Illumina sequencing of PCR-amplified mtDNA was performed to analyze sequence and extent of heteroplasmy of mtDNAs of 193 cases and 196 age- and gender-matched controls from DNA samples collected by the Chronic Fatigue Initiative. Association testing was carried out to examine possible correlations of mitochondrial sequences with case/control status and symptom constellation and severity as reported by subjects on Short Form-36 and DePaul Symptom Questionnaires. Results No ME/CFS subject exhibited known disease-causing mtDNA mutations. Extent of heteroplasmy was low in all subjects. Although no association between mtDNA SNPs and ME/CFS vs. healthy status was observed, haplogroups J, U and H as well as eight SNPs in ME/CFS cases were significantly associated with individual symptoms, symptom clusters, or symptom severity. Conclusions Analysis of mitochondrial genomes in ME/CFS cases indicates that individuals of a certain haplogroup or carrying specific SNPs are more likely to exhibit certain neurological, inflammatory, and/or gastrointestinal symptoms. No increase in susceptibility to ME/CFS of individuals carrying particular mitochondrial genomes or SNPs was observed. Electronic supplementary material The online version of this article (doi:10.1186/s12967-016-0771-6) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Paul Billing-Ross
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, 14853, USA.
| | - Arnaud Germain
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14853, USA.
| | - Kaixiong Ye
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY, 14853, USA.
| | - Alon Keinan
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY, 14853, USA.
| | - Zhenglong Gu
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, 14853, USA.
| | - Maureen R Hanson
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14853, USA.
| |
Collapse
|
37
|
TEZEL A, ÇETİNKAYA Ö, GÜZELTEPE B, KILIÇ N. Genetic identification with heteroplasmic variations in maternally relatedindividuals in forensic cases. Turk J Biol 2016. [DOI: 10.3906/biy-1506-62] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
|
38
|
Halley YA, Oldeschulte DL, Bhattarai EK, Hill J, Metz RP, Johnson CD, Presley SM, Ruzicka RE, Rollins D, Peterson MJ, Murphy WJ, Seabury CM. Northern Bobwhite (Colinus virginianus) Mitochondrial Population Genomics Reveals Structure, Divergence, and Evidence for Heteroplasmy. PLoS One 2015; 10:e0144913. [PMID: 26713762 PMCID: PMC4699210 DOI: 10.1371/journal.pone.0144913] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 11/26/2015] [Indexed: 01/09/2023] Open
Abstract
Herein, we evaluated the concordance of population inferences and conclusions resulting from the analysis of short mitochondrial fragments (i.e., partial or complete D-Loop nucleotide sequences) versus complete mitogenome sequences for 53 bobwhites representing six ecoregions across TX and OK (USA). Median joining (MJ) haplotype networks demonstrated that analyses performed using small mitochondrial fragments were insufficient for estimating the true (i.e., complete) mitogenome haplotype structure, corresponding levels of divergence, and maternal population history of our samples. Notably, discordant demographic inferences were observed when mismatch distributions of partial (i.e., partial D-Loop) versus complete mitogenome sequences were compared, with the reduction in mitochondrial genomic information content observed to encourage spurious inferences in our samples. A probabilistic approach to variant prediction for the complete bobwhite mitogenomes revealed 344 segregating sites corresponding to 347 total mutations, including 49 putative nonsynonymous single nucleotide variants (SNVs) distributed across 12 protein coding genes. Evidence of gross heteroplasmy was observed for 13 bobwhites, with 10 of the 13 heteroplasmies involving one moderate to high frequency SNV. Haplotype network and phylogenetic analyses for the complete bobwhite mitogenome sequences revealed two divergent maternal lineages (dXY = 0.00731; FST = 0.849; P < 0.05), thereby supporting the potential for two putative subspecies. However, the diverged lineage (n = 103 variants) almost exclusively involved bobwhites geographically classified as Colinus virginianus texanus, which is discordant with the expectations of previous geographic subspecies designations. Tests of adaptive evolution for functional divergence (MKT), frequency distribution tests (D, FS) and phylogenetic analyses (RAxML) provide no evidence for positive selection or hybridization with the sympatric scaled quail (Callipepla squamata) as being explanatory factors for the two bobwhite maternal lineages observed. Instead, our analyses support the supposition that two diverged maternal lineages have survived from pre-expansion to post-expansion population(s), with the segregation of some slightly deleterious nonsynonymous mutations.
Collapse
Affiliation(s)
- Yvette A. Halley
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, Texas, United States of America
| | - David L. Oldeschulte
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, Texas, United States of America
| | - Eric K. Bhattarai
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, Texas, United States of America
| | - Joshua Hill
- Genomics and Bioinformatics Core, Texas A&M AgriLife Research, College Station, Texas, United States of America
| | - Richard P. Metz
- Genomics and Bioinformatics Core, Texas A&M AgriLife Research, College Station, Texas, United States of America
| | - Charles D. Johnson
- Genomics and Bioinformatics Core, Texas A&M AgriLife Research, College Station, Texas, United States of America
| | - Steven M. Presley
- Department of Environmental Toxicology, Institute of Environmental and Human Health, Texas Tech University, Lubbock, Texas, United States of America
| | - Rebekah E. Ruzicka
- Texas A&M AgriLife Extension Service, Dallas, Texas, United States of America
| | - Dale Rollins
- Rolling Plains Quail Research Ranch, 1262 U.S. Highway 180 W., Rotan, Texas, United States of America
| | - Markus J. Peterson
- Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas, United States of America
| | - William J. Murphy
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine, Texas A&M University, College Station, Texas, United States of America
| | - Christopher M. Seabury
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, Texas, United States of America
- * E-mail:
| |
Collapse
|
39
|
Vellarikkal SK, Dhiman H, Joshi K, Hasija Y, Sivasubbu S, Scaria V. mit-o-matic: a comprehensive computational pipeline for clinical evaluation of mitochondrial variations from next-generation sequencing datasets. Hum Mutat 2015; 36:419-24. [PMID: 25677119 DOI: 10.1002/humu.22767] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 01/26/2015] [Indexed: 12/27/2022]
Abstract
The human mitochondrial genome has been reported to have a very high mutation rate as compared with the nuclear genome. A large number of mitochondrial mutations show significant phenotypic association and are involved in a broad spectrum of diseases. In recent years, there has been a remarkable progress in the understanding of mitochondrial genetics. The availability of next-generation sequencing (NGS) technologies have not only reduced sequencing cost by orders of magnitude but has also provided us good quality mitochondrial genome sequences with high coverage, thereby enabling decoding of a number of human mitochondrial diseases. In this study, we report a computational and experimental pipeline to decipher the human mitochondrial DNA variations and examine them for their clinical correlation. As a proof of principle, we also present a clinical study of a patient with Leigh disease and confirmed maternal inheritance of the causative allele. The pipeline is made available as a user-friendly online tool to annotate variants and find haplogroup, disease association, and heteroplasmic sites. The "mit-o-matic" computational pipeline represents a comprehensive cloud-based tool for clinical evaluation of mitochondrial genomic variations from NGS datasets. The tool is freely available at http://genome.igib.res.in/mitomatic/.
Collapse
Affiliation(s)
- Shamsudheen Karuthedath Vellarikkal
- Genomics and Molecular Medicine, CSIR Institute of Genomics and Integrative Biology, Delhi, India; Academy of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, Delhi, India
| | | | | | | | | | | |
Collapse
|
40
|
Coxhead J, Kurzawa-Akanbi M, Hussain R, Pyle A, Chinnery P, Hudson G. Somatic mtDNA variation is an important component of Parkinson's disease. Neurobiol Aging 2015; 38:217.e1-217.e6. [PMID: 26639157 PMCID: PMC4759607 DOI: 10.1016/j.neurobiolaging.2015.10.036] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 10/29/2015] [Accepted: 10/30/2015] [Indexed: 11/30/2022]
Abstract
There is a growing body of evidence linking mitochondrial dysfunction, mediated either through inherited mitochondrial DNA (mtDNA) variation or mitochondrial proteomic deficit, to Parkinson's disease (PD). Yet, despite this, the role of somatic mtDNA point mutations and specifically point-mutational burden in PD is poorly understood. Here, we take advantage of recent technical and methodological advances to examine the role of age-related and acquired mtDNA mutation in the largest study of mtDNA in postmortem PD tissue to date. Our data show that PD patients suffer an increase in mtDNA mutational burden in, but no limited to, the substantia nigra pars compacta when compared to matched controls. This mutational burden appears increased in genes encoding cytochrome c oxidase, supportive of previous protein studies of mitochondrial dysfunction in PD. Accepting experimental limitations, our study confirms the important role of age-related mtDNA point mutation in the etiology of PD, moreover, by analyzing 2 distinct brain regions, we are able to show that PD patient brains are more vulnerable to mtDNA mutation overall.
Collapse
Affiliation(s)
- Jonathan Coxhead
- Mitochondrial Research Group, Institute of Genetic Medicine, University of Newcastle Upon Tyne, UK
| | - Marzena Kurzawa-Akanbi
- Mitochondrial Research Group, Institute of Genetic Medicine, University of Newcastle Upon Tyne, UK
| | - Rafiqul Hussain
- Mitochondrial Research Group, Institute of Genetic Medicine, University of Newcastle Upon Tyne, UK
| | - Angela Pyle
- Mitochondrial Research Group, Institute of Genetic Medicine, University of Newcastle Upon Tyne, UK
| | - Patrick Chinnery
- Mitochondrial Research Group, Institute of Genetic Medicine, University of Newcastle Upon Tyne, UK
| | - Gavin Hudson
- Mitochondrial Research Group, Institute of Genetic Medicine, University of Newcastle Upon Tyne, UK.
| |
Collapse
|
41
|
Gutiérrez V, Rego N, Naya H, García G. First complete mitochondrial genome of the South American annual fish Austrolebias charrua (Cyprinodontiformes: Rivulidae): peculiar features among cyprinodontiforms mitogenomes. BMC Genomics 2015; 16:879. [PMID: 26511223 PMCID: PMC4625726 DOI: 10.1186/s12864-015-2090-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 10/15/2015] [Indexed: 11/10/2022] Open
Abstract
Background Among teleosts, the South American genus Austrolebias (Cyprinodontiformes: Rivulidae) includes 42 taxa of annual fishes divided into five different species groups. It is a monophyletic genus, but morphological and molecular data do not resolve the relationship among intrageneric clades and high rates of substitution have been previously described in some mitochondrial genes. In this work, the complete mitogenome of a species of the genus was determined for the first time. We determined its structure, gene order and evolutionary peculiar features, which will allow us to evaluate the performance of mitochondrial genes in the phylogenetic resolution at different taxonomic levels. Results Regarding gene content and order, the circular mitogenome of A. charrua (17,271 pb) presents the typical pattern of vertebrate mitogenomes. It contains the full complement of 13 proteins-coding genes, 22 tRNA, 2 rRNA and one non-coding control region. Notably, the tRNA-Cys was only 57 bp in length and lacks the D-loop arm. In three full sibling individuals, heteroplasmatic condition was detected due to a total of 12 variable sites in seven protein-coding genes. Among cyprinodontiforms, the mitogenome of A. charrua exhibits the lowest G+C content (37 %) and GCskew, as well as the highest strand asymmetry with a net difference of T over A at 1st and 3rd codon positions. Considering the 12 coding-genes of the H strand, correspondence analyses of nucleotide composition and codon usage show that A and T at 1st and 3rd codon positions have the highest weight in the first axis, and segregate annual species from the other cyprinodontiforms analyzed. Given the annual life-style, their mitogenomes could be under different selective pressures. All 13 protein-coding genes are under strong purifying selection and we did not find any significant evidence of nucleotide sites showing episodic selection (dN >dS) at annual lineages. When fast evolving third codon positions were removed from alignments, the “supergene” tree recovers our reference species phylogeny as well as the Cytb, ND4L and ND6 genes. Therefore, third codon positions seem to be saturated in the aforementioned coding regions at intergeneric Cyprinodontiformes comparisons. Conclusions The complete mitogenome obtained in present work, offers relevant data for further comparative studies on molecular phylogeny and systematics of this taxonomic controversial endemic genus of annual fishes. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-2090-3) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Verónica Gutiérrez
- Sección Genética Evolutiva, Facultad de Ciencias, Universidad de la República, Iguá 4225 (CP.11400), Montevideo, Uruguay.
| | - Natalia Rego
- Institut Pasteur de Montevideo, Unidad de Bioinformática, Montevideo, Uruguay.
| | - Hugo Naya
- Institut Pasteur de Montevideo, Unidad de Bioinformática, Montevideo, Uruguay. .,Departamento de Producción Animal y Pasturas, Facultad de Agronomía, Universidad de la República, Paysandú, Uruguay.
| | - Graciela García
- Sección Genética Evolutiva, Facultad de Ciencias, Universidad de la República, Iguá 4225 (CP.11400), Montevideo, Uruguay.
| |
Collapse
|
42
|
Assessing Mitochondrial DNA Variation and Copy Number in Lymphocytes of ~2,000 Sardinians Using Tailored Sequencing Analysis Tools. PLoS Genet 2015; 11:e1005306. [PMID: 26172475 PMCID: PMC4501845 DOI: 10.1371/journal.pgen.1005306] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Accepted: 05/28/2015] [Indexed: 12/21/2022] Open
Abstract
DNA sequencing identifies common and rare genetic variants for association studies, but studies typically focus on variants in nuclear DNA and ignore the mitochondrial genome. In fact, analyzing variants in mitochondrial DNA (mtDNA) sequences presents special problems, which we resolve here with a general solution for the analysis of mtDNA in next-generation sequencing studies. The new program package comprises 1) an algorithm designed to identify mtDNA variants (i.e., homoplasmies and heteroplasmies), incorporating sequencing error rates at each base in a likelihood calculation and allowing allele fractions at a variant site to differ across individuals; and 2) an estimation of mtDNA copy number in a cell directly from whole-genome sequencing data. We also apply the methods to DNA sequence from lymphocytes of ~2,000 SardiNIA Project participants. As expected, mothers and offspring share all homoplasmies but a lesser proportion of heteroplasmies. Both homoplasmies and heteroplasmies show 5-fold higher transition/transversion ratios than variants in nuclear DNA. Also, heteroplasmy increases with age, though on average only ~1 heteroplasmy reaches the 4% level between ages 20 and 90. In addition, we find that mtDNA copy number averages ~110 copies/lymphocyte and is ~54% heritable, implying substantial genetic regulation of the level of mtDNA. Copy numbers also decrease modestly but significantly with age, and females on average have significantly more copies than males. The mtDNA copy numbers are significantly associated with waist circumference (p-value = 0.0031) and waist-hip ratio (p-value = 2.4×10-5), but not with body mass index, indicating an association with central fat distribution. To our knowledge, this is the largest population analysis to date of mtDNA dynamics, revealing the age-imposed increase in heteroplasmy, the relatively high heritability of copy number, and the association of copy number with metabolic traits. We present a new program that provides a general solution for the analysis of variation of mtDNA (the small circular genome in mitochondria, separate from the DNA in the nucleus). This is needed because many large-scale genetic studies are using new DNA sequencing technologies to help assess genetic variation and its effects on disease, but the mitochondrial genome is often ignored because it exists in many copies in a cell, complicating analyses. Our approach both identifies variants on mitochondrial genome and estimates mtDNA copy number. Applying the programs to DNA sequence from ~2,000 SardiNIA project participants, we show that heteroplasmies (mtDNA variants with more than one allele at a DNA site) increase with age, and that copy number is relatively highly heritable and is correlated with metabolic traits, particularly central fat levels. The program package can facilitate comprehensive mtDNA analysis from any whole-genome sequencing data, with an increase in the understanding of mtDNA dynamics and its potential role in aging and metabolism.
Collapse
|
43
|
Mitochondrial DNA: Radically free of free-radical driven mutations. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:1354-61. [PMID: 26050972 DOI: 10.1016/j.bbabio.2015.06.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 05/08/2015] [Accepted: 06/02/2015] [Indexed: 01/31/2023]
Abstract
Mitochondrial DNA has long been posited as a likely target of oxidative damage induced mutation during the ageing process. Research over the past decades has uncovered the accumulation of mitochondrial DNA mutations in association with a mosaic pattern of cells displaying mitochondrial dysfunction in ageing individuals. Unfortunately, the underlying mechanisms are far less straightforward than originally anticipated. Recent research on mitochondria reveals that these genomes are far less helpless than originally envisioned. Additionally, new technologies have allowed us to analyze the mutational signatures of many more somatic mitochondrial DNA mutations, revealing surprising patterns that are inconsistent with a DNA-oxidative damage based hypothesis. In this review, we will discuss these recent observations and new insights into the eccentricities of mitochondrial genetics, and their impact on our understanding of mitochondrial mutations and their role in the ageing process. This article is part of a Special Issue entitled: Mitochondrial Dysfunction in Aging.
Collapse
|
44
|
Sequeira A, Rollins B, Magnan C, van Oven M, Baldi P, Myers RM, Barchas JD, Schatzberg AF, Watson SJ, Akil H, Bunney WE, Vawter MP. Mitochondrial mutations in subjects with psychiatric disorders. PLoS One 2015; 10:e0127280. [PMID: 26011537 PMCID: PMC4444211 DOI: 10.1371/journal.pone.0127280] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 04/13/2015] [Indexed: 11/30/2022] Open
Abstract
A considerable body of evidence supports the role of mitochondrial dysfunction in psychiatric disorders and mitochondrial DNA (mtDNA) mutations are known to alter brain energy metabolism, neurotransmission, and cause neurodegenerative disorders. Genetic studies focusing on common nuclear genome variants associated with these disorders have produced genome wide significant results but those studies have not directly studied mtDNA variants. The purpose of this study is to investigate, using next generation sequencing, the involvement of mtDNA variation in bipolar disorder, schizophrenia, major depressive disorder, and methamphetamine use. MtDNA extracted from multiple brain regions and blood were sequenced (121 mtDNA samples with an average of 8,800x coverage) and compared to an electronic database containing 26,850 mtDNA genomes. We confirmed novel and rare variants, and confirmed next generation sequencing error hotspots by traditional sequencing and genotyping methods. We observed a significant increase of non-synonymous mutations found in individuals with schizophrenia. Novel and rare non-synonymous mutations were found in psychiatric cases in mtDNA genes: ND6, ATP6, CYTB, and ND2. We also observed mtDNA heteroplasmy in brain at a locus previously associated with schizophrenia (T16519C). Large differences in heteroplasmy levels across brain regions within subjects suggest that somatic mutations accumulate differentially in brain regions. Finally, multiplasmy, a heteroplasmic measure of repeat length, was observed in brain from selective cases at a higher frequency than controls. These results offer support for increased rates of mtDNA substitutions in schizophrenia shown in our prior results. The variable levels of heteroplasmic/multiplasmic somatic mutations that occur in brain may be indicators of genetic instability in mtDNA.
Collapse
Affiliation(s)
- Adolfo Sequeira
- Functional Genomics Laboratory, Department of Psychiatry & Human Behavior, University of California Irvine, Irvine, California, United States of America
| | - Brandi Rollins
- Functional Genomics Laboratory, Department of Psychiatry & Human Behavior, University of California Irvine, Irvine, California, United States of America
| | - Christophe Magnan
- School of Information and Computer Sciences (ICS), Institute for Genomics and Bioinformatics (IGB), University of California Irvine, Irvine, California, United States of America
| | - Mannis van Oven
- Department of Forensic Molecular Biology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Pierre Baldi
- School of Information and Computer Sciences (ICS), Institute for Genomics and Bioinformatics (IGB), University of California Irvine, Irvine, California, United States of America
| | - Richard M. Myers
- HudsonAlpha Institute for Biotechnology, Huntsville, Alabama, United States of America
| | - Jack D. Barchas
- Department of Psychiatry, Weill Cornell Medical College, New York, New York, United States of America
| | - Alan F. Schatzberg
- Department of Psychiatry & Behavioral Sciences, Stanford University, Palo Alto, California, United States of America
| | - Stanley J. Watson
- Molecular and Behavioral Neurosciences Institute, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Huda Akil
- Molecular and Behavioral Neurosciences Institute, University of Michigan, Ann Arbor, Michigan, United States of America
| | - William E. Bunney
- Department of Psychiatry & Human Behavior, University of California Irvine, Irvine, California, United States of America
| | - Marquis P. Vawter
- Functional Genomics Laboratory, Department of Psychiatry & Human Behavior, University of California Irvine, Irvine, California, United States of America
- * E-mail:
| |
Collapse
|
45
|
Just RS, Irwin JA, Parson W. Mitochondrial DNA heteroplasmy in the emerging field of massively parallel sequencing. Forensic Sci Int Genet 2015; 18:131-9. [PMID: 26009256 PMCID: PMC4550493 DOI: 10.1016/j.fsigen.2015.05.003] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 04/24/2015] [Accepted: 05/05/2015] [Indexed: 12/12/2022]
Abstract
Long an important and useful tool in forensic genetic investigations, mitochondrial DNA (mtDNA) typing continues to mature. Research in the last few years has demonstrated both that data from the entire molecule will have practical benefits in forensic DNA casework, and that massively parallel sequencing (MPS) methods will make full mitochondrial genome (mtGenome) sequencing of forensic specimens feasible and cost-effective. A spate of recent studies has employed these new technologies to assess intraindividual mtDNA variation. However, in several instances, contamination and other sources of mixed mtDNA data have been erroneously identified as heteroplasmy. Well vetted mtGenome datasets based on both Sanger and MPS sequences have found authentic point heteroplasmy in approximately 25% of individuals when minor component detection thresholds are in the range of 10-20%, along with positional distribution patterns in the coding region that differ from patterns of point heteroplasmy in the well-studied control region. A few recent studies that examined very low-level heteroplasmy are concordant with these observations when the data are examined at a common level of resolution. In this review we provide an overview of considerations related to the use of MPS technologies to detect mtDNA heteroplasmy. In addition, we examine published reports on point heteroplasmy to characterize features of the data that will assist in the evaluation of future mtGenome data developed by any typing method.
Collapse
Affiliation(s)
- Rebecca S Just
- Armed Forces DNA Identification Laboratory, Armed Forces Medical Examiner System, Dover, DE, USA; American Registry of Pathology, Rockville, MD, USA
| | | | - Walther Parson
- Institute of Legal Medicine, Medical University of Innsbruck, Innsbruck, Austria; Forensic Science Program, The Pennsylvania State University, University Park, PA, USA.
| |
Collapse
|
46
|
Jayaprakash AD, Benson EK, Gone S, Liang R, Shim J, Lambertini L, Toloue MM, Wigler M, Aaronson SA, Sachidanandam R. Stable heteroplasmy at the single-cell level is facilitated by intercellular exchange of mtDNA. Nucleic Acids Res 2015; 43:2177-87. [PMID: 25653158 PMCID: PMC4344500 DOI: 10.1093/nar/gkv052] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 01/13/2015] [Accepted: 01/14/2015] [Indexed: 12/23/2022] Open
Abstract
Eukaryotic cells carry two genomes, nuclear (nDNA) and mitochondrial (mtDNA), which are ostensibly decoupled in their replication, segregation and inheritance. It is increasingly appreciated that heteroplasmy, the occurrence of multiple mtDNA haplotypes in a cell, plays an important biological role, but its features are not well understood. Accurately determining the diversity of mtDNA has been difficult, due to the relatively small amount of mtDNA in each cell (<1% of the total DNA), the intercellular variability of mtDNA content and mtDNA pseudogenes (Numts) in nDNA. To understand the nature of heteroplasmy, we developed Mseek, a novel technique to purify and sequence mtDNA. Mseek yields high purity (>90%) mtDNA and its ability to detect rare variants is limited only by sequencing depth, providing unprecedented sensitivity and specificity. Using Mseek, we confirmed the ubiquity of heteroplasmy by analyzing mtDNA from a diverse set of cell lines and human samples. Applying Mseek to colonies derived from single cells, we find heteroplasmy is stably maintained in individual daughter cells over multiple cell divisions. We hypothesized that the stability of heteroplasmy could be facilitated by intercellular exchange of mtDNA. We explicitly demonstrate this exchange by co-culturing cell lines with distinct mtDNA haplotypes. Our results shed new light on the maintenance of heteroplasmy and provide a novel platform to investigate features of heteroplasmy in normal and diseased states.
Collapse
Affiliation(s)
- Anitha D Jayaprakash
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, NY 10029, USA
| | - Erica K Benson
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, NY 10029, USA
| | - Swapna Gone
- Bioo Scientific Corporation, 7050 Burleson Road, Austin, TX 78744, USA
| | - Raymond Liang
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, NY 10029, USA
| | - Jaehee Shim
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, NY 10029, USA
| | - Luca Lambertini
- Department of Preventive Medicine and Department of Obstetrics, Gynecology and Reproductive Science, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, NY 10029, USA
| | - Masoud M Toloue
- Bioo Scientific Corporation, 7050 Burleson Road, Austin, TX 78744, USA
| | - Mike Wigler
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Stuart A Aaronson
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, NY 10029, USA
| | - Ravi Sachidanandam
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, NY 10029, USA
| |
Collapse
|
47
|
Levin L, Blumberg A, Barshad G, Mishmar D. Mito-nuclear co-evolution: the positive and negative sides of functional ancient mutations. Front Genet 2014; 5:448. [PMID: 25566330 PMCID: PMC4274989 DOI: 10.3389/fgene.2014.00448] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 12/08/2014] [Indexed: 12/31/2022] Open
Abstract
Most cell functions are carried out by interacting factors, thus underlying the functional importance of genetic interactions between genes, termed epistasis. Epistasis could be under strong selective pressures especially in conditions where the mutation rate of one of the interacting partners notably differs from the other. Accordingly, the order of magnitude higher mitochondrial DNA (mtDNA) mutation rate as compared to the nuclear DNA (nDNA) of all tested animals, should influence systems involving mitochondrial-nuclear (mito-nuclear) interactions. Such is the case of the energy producing oxidative phosphorylation (OXPHOS) and mitochondrial translational machineries which are comprised of factors encoded by both the mtDNA and the nDNA. Additionally, the mitochondrial RNA transcription and mtDNA replication systems are operated by nDNA-encoded proteins that bind mtDNA regulatory elements. As these systems are central to cell life there is strong selection toward mito-nuclear co-evolution to maintain their function. However, it is unclear whether (A) mito-nuclear co-evolution befalls only to retain mitochondrial functions during evolution or, also, (B) serves as an adaptive tool to adjust for the evolving energetic demands as species' complexity increases. As the first step to answer these questions we discuss evidence of both negative and adaptive (positive) selection acting on the mtDNA and nDNA-encoded genes and the effect of both types of selection on mito-nuclear interacting factors. Emphasis is given to the crucial role of recurrent ancient (nodal) mutations in such selective events. We apply this point-of-view to the three available types of mito-nuclear co-evolution: protein-protein (within the OXPHOS system), protein-RNA (mainly within the mitochondrial ribosome), and protein-DNA (at the mitochondrial replication and transcription machineries).
Collapse
Affiliation(s)
- Liron Levin
- Department of Life Sciences, Ben-Gurion University of the Negev Beersheba, Israel
| | - Amit Blumberg
- Department of Life Sciences, Ben-Gurion University of the Negev Beersheba, Israel
| | - Gilad Barshad
- Department of Life Sciences, Ben-Gurion University of the Negev Beersheba, Israel
| | - Dan Mishmar
- Department of Life Sciences, Ben-Gurion University of the Negev Beersheba, Israel
| |
Collapse
|
48
|
Naue J, Hörer S, Sänger T, Strobl C, Hatzer-Grubwieser P, Parson W, Lutz-Bonengel S. Evidence for frequent and tissue-specific sequence heteroplasmy in human mitochondrial DNA. Mitochondrion 2014; 20:82-94. [PMID: 25526677 DOI: 10.1016/j.mito.2014.12.002] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 12/02/2014] [Accepted: 12/09/2014] [Indexed: 10/24/2022]
Abstract
Mitochondrial point heteroplasmy is a common event observed not only in patients with mitochondrial diseases but also in healthy individuals. We here report a comprehensive investigation of heteroplasmy occurrence in human including the whole mitochondrial control region from nine different tissue types of 100 individuals. Sanger sequencing was used as a standard method and results were supported by cloning, minisequencing, and massively parallel sequencing. Only 12% of all individuals showed no heteroplasmy, whereas 88% showed at least one heteroplasmic position within the investigated tissues. In 66% of individuals up to 8 positions were affected. The highest relative number of heteroplasmies was detected in muscle and liver (79%, 69%), followed by brain, hair, and heart (36.7%-30.2%). Lower percentages were observed in bone, blood, lung, and buccal cells (19.8%-16.2%). Accumulation of position-specific heteroplasmies was found in muscle (positions 64, 72, 73, 189, and 408), liver (position 72) and brain (partial deletion at position 71). Deeper analysis of these specific positions in muscle revealed a non-random appearance and position-specific dependency on age. MtDNA heteroplasmy frequency and its potential functional importance have been underestimated in the past and its occurrence is ubiquitous and dependent at least on age, tissue, and position-specific mutation rates.
Collapse
Affiliation(s)
- Jana Naue
- Institute of Legal Medicine, Freiburg University Medical Center, Albertstrasse 9, D-79104 Freiburg, Germany; Faculty of Biology, University of Freiburg, Schaenzlestrasse 1, D-79104 Freiburg, Germany.
| | - Steffen Hörer
- Institute of Legal Medicine, Freiburg University Medical Center, Albertstrasse 9, D-79104 Freiburg, Germany.
| | - Timo Sänger
- Institute of Legal Medicine, Freiburg University Medical Center, Albertstrasse 9, D-79104 Freiburg, Germany.
| | - Christina Strobl
- Institute of Legal Medicine, Innsbruck Medical University, Muellerstrasse 44, A-6020 Innsbruck, Austria.
| | - Petra Hatzer-Grubwieser
- Institute of Legal Medicine, Innsbruck Medical University, Muellerstrasse 44, A-6020 Innsbruck, Austria.
| | - Walther Parson
- Institute of Legal Medicine, Innsbruck Medical University, Muellerstrasse 44, A-6020 Innsbruck, Austria; Penn State Eberly College of Science, University Park, PA, USA.
| | - Sabine Lutz-Bonengel
- Institute of Legal Medicine, Freiburg University Medical Center, Albertstrasse 9, D-79104 Freiburg, Germany.
| |
Collapse
|
49
|
Dayama G, Emery SB, Kidd JM, Mills RE. The genomic landscape of polymorphic human nuclear mitochondrial insertions. Nucleic Acids Res 2014; 42:12640-9. [PMID: 25348406 PMCID: PMC4227756 DOI: 10.1093/nar/gku1038] [Citation(s) in RCA: 124] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The transfer of mitochondrial genetic material into the nuclear genomes of eukaryotes is a well-established phenomenon that has been previously limited to the study of static reference genomes. The recent advancement of high throughput sequencing has enabled an expanded exploration into the diversity of polymorphic nuclear mitochondrial insertions (NumtS) within human populations. We have developed an approach to discover and genotype novel Numt insertions using whole genome, paired-end sequencing data. We have applied this method to a thousand individuals in 20 populations from the 1000 Genomes Project and other datasets and identified 141 new sites of Numt insertions, extending our current knowledge of existing NumtS by almost 20%. We find that recent Numt insertions are derived from throughout the mitochondrial genome, including the D-loop, and have integration biases that differ in some respects from previous studies on older, fixed NumtS in the reference genome. We determined the complete inserted sequence for a subset of these events and have identified a number of nearly full-length mitochondrial genome insertions into nuclear chromosomes. We further define their age and origin of insertion and present an analysis of their potential impact to ongoing studies of mitochondrial heteroplasmy and disease.
Collapse
Affiliation(s)
- Gargi Dayama
- Department of Computational Medicine & Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Sarah B Emery
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jeffrey M Kidd
- Department of Computational Medicine & Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ryan E Mills
- Department of Computational Medicine & Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
| |
Collapse
|
50
|
Reply to Just et al.: Mitochondrial DNA heteroplasmy could be reliably detected with massively parallel sequencing technologies. Proc Natl Acad Sci U S A 2014; 111:E4548-50. [PMID: 25319265 DOI: 10.1073/pnas.1415171111] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|