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Lu N, Qiao Y, An P, Luo J, Bi C, Li M, Lu Z, Tu J. Exploration of whole genome amplification generated chimeric sequences in long-read sequencing data. Brief Bioinform 2023; 24:bbad275. [PMID: 37529913 DOI: 10.1093/bib/bbad275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 06/21/2023] [Accepted: 07/10/2023] [Indexed: 08/03/2023] Open
Abstract
MOTIVATION Multiple displacement amplification (MDA) has become the most commonly used method of whole genome amplification, generating a vast amount of DNA with higher molecular weight and greater genome coverage. Coupling with long-read sequencing, it is possible to sequence the amplicons of over 20 kb in length. However, the formation of chimeric sequences (chimeras, expressed as structural errors in sequencing data) in MDA seriously interferes with the bioinformatics analysis but its influence on long-read sequencing data is unknown. RESULTS We sequenced the phi29 DNA polymerase-mediated MDA amplicons on the PacBio platform and analyzed chimeras within the generated data. The 3rd-ChimeraMiner has been constructed as a pipeline for recognizing and restoring chimeras into the original structures in long-read sequencing data, improving the efficiency of using TGS data. Five long-read datasets and one high-fidelity long-read dataset with various amplification folds were analyzed. The result reveals that the mis-priming events in amplification are more frequently occurring than widely perceived, and the propor tion gradually accumulates from 42% to over 78% as the amplification continues. In total, 99.92% of recognized chimeric sequences were demonstrated to be artifacts, whose structures were wrongly formed in MDA instead of existing in original genomes. By restoring chimeras to their original structures, the vast majority of supplementary alignments that introduce false-positive structural variants are recycled, removing 97% of inversions on average and contributing to the analysis of structural variation in MDA-amplified samples. The impact of chimeras in long-read sequencing data analysis should be emphasized, and the 3rd-ChimeraMiner can help to quantify and reduce the influence of chimeras. AVAILABILITY AND IMPLEMENTATION The 3rd-ChimeraMiner is available on GitHub, https://github.com/dulunar/3rdChimeraMiner.
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Affiliation(s)
- Na Lu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Yi Qiao
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Pengfei An
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
- Monash University-Southeast University Joint Research Institute, Suzhou 215123, China
| | - Jiajian Luo
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Changwei Bi
- College of Information Science and Technology, Nanjing Forestry University, Nanjing 210037, China
| | - Musheng Li
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89511, USA
| | - Zuhong Lu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Jing Tu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
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Zhong Y, Zeng K, Adnan A, Li YZ, Hou XK, Pan Y, Li A, Zhu XM, Lv P, Du Z, Yang Y, Yao J. Discrimination of monozygotic twins using mtDNA heteroplasmy through probe capture enrichment and massively parallel sequencing. Int J Legal Med 2023; 137:1337-1345. [PMID: 37270462 DOI: 10.1007/s00414-023-03033-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 05/30/2023] [Indexed: 06/05/2023]
Abstract
Differentiating between monozygotic (MZ) twins remains difficult because they have the same genetic makeup. Applying the traditional STR genotyping approach cannot differentiate one from the other. Heteroplasmy refers to the presence of two or more different mtDNA copies within a single cell and this phenomenon is common in humans. The levels of heteroplasmy cannot change dramatically during transmission in the female germ line but increase or decrease during germ-line transmission and in somatic tissues during life. As massively parallel sequencing (MPS) technology has advanced, it has shown the extraordinary quantity of mtDNA heteroplasmy in humans. In this study, a probe hybridization technique was used to obtain mtDNA and then MPS was performed with an average sequencing depth of above 4000. The results showed us that all ten pairs of MZ twins were clearly differentiated with the minor heteroplasmy threshold at 1.0%, 0.5%, and 0.1%, respectively. Finally, we used a probe that targeted mtDNA to boost sequencing depth without interfering with nuclear DNA and this technique can be used in forensic genetics to differentiate the MZ twins.
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Affiliation(s)
- Yang Zhong
- School of Forensic Medicine, China Medical University, No.77, Puhe Road, Shenbei New District, Shenyang, 110122, People's Republic of China
- Key Laboratory of Forensic Bio-evidence Sciences, Shenyang, Liaoning Province, China
- China Medical University Center of Forensic Investigation, Chengdu, China
| | - Kuo Zeng
- Institute of Evidence Law and Forensic Science, China University of Political Science and Law, Beijing, China
| | - Atif Adnan
- Department of Forensic Sciences, College of Criminal Justice, Naif University of Security Sciences, Riyadh, 11452, Kingdom of Saudi Arabia
| | - Yu-Zhang Li
- School of Forensic Medicine, China Medical University, No.77, Puhe Road, Shenbei New District, Shenyang, 110122, People's Republic of China
- Key Laboratory of Forensic Bio-evidence Sciences, Shenyang, Liaoning Province, China
- China Medical University Center of Forensic Investigation, Chengdu, China
| | - Xi-Kai Hou
- School of Forensic Medicine, China Medical University, No.77, Puhe Road, Shenbei New District, Shenyang, 110122, People's Republic of China
- Key Laboratory of Forensic Bio-evidence Sciences, Shenyang, Liaoning Province, China
- China Medical University Center of Forensic Investigation, Chengdu, China
| | - Ying Pan
- School of Forensic Medicine, China Medical University, No.77, Puhe Road, Shenbei New District, Shenyang, 110122, People's Republic of China
- Key Laboratory of Forensic Bio-evidence Sciences, Shenyang, Liaoning Province, China
- China Medical University Center of Forensic Investigation, Chengdu, China
| | - Ang Li
- School of Forensic Medicine, China Medical University, No.77, Puhe Road, Shenbei New District, Shenyang, 110122, People's Republic of China
- Key Laboratory of Forensic Bio-evidence Sciences, Shenyang, Liaoning Province, China
- China Medical University Center of Forensic Investigation, Chengdu, China
| | - Xiu-Mei Zhu
- School of Forensic Medicine, China Medical University, No.77, Puhe Road, Shenbei New District, Shenyang, 110122, People's Republic of China
- Key Laboratory of Forensic Bio-evidence Sciences, Shenyang, Liaoning Province, China
- China Medical University Center of Forensic Investigation, Chengdu, China
| | - Peng Lv
- School of Forensic Medicine, China Medical University, No.77, Puhe Road, Shenbei New District, Shenyang, 110122, People's Republic of China
- Key Laboratory of Forensic Bio-evidence Sciences, Shenyang, Liaoning Province, China
- China Medical University Center of Forensic Investigation, Chengdu, China
| | - Zhe Du
- School of Forensic Medicine, China Medical University, No.77, Puhe Road, Shenbei New District, Shenyang, 110122, People's Republic of China
- Key Laboratory of Forensic Bio-evidence Sciences, Shenyang, Liaoning Province, China
- China Medical University Center of Forensic Investigation, Chengdu, China
| | - Ying Yang
- Department of Gastroenterology, Shengjing Hospital of China Medical University, Shenyang, China.
| | - Jun Yao
- School of Forensic Medicine, China Medical University, No.77, Puhe Road, Shenbei New District, Shenyang, 110122, People's Republic of China.
- Key Laboratory of Forensic Bio-evidence Sciences, Shenyang, Liaoning Province, China.
- China Medical University Center of Forensic Investigation, Chengdu, China.
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Lu N, Qiao Y, Lu Z, Tu J. Chimera: The spoiler in multiple displacement amplification. Comput Struct Biotechnol J 2023; 21:1688-1696. [PMID: 36879882 PMCID: PMC9984789 DOI: 10.1016/j.csbj.2023.02.034] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 02/18/2023] [Accepted: 02/18/2023] [Indexed: 02/24/2023] Open
Abstract
Multiple displacement amplification (MDA) based on isothermal random priming and high fidelity phi29 DNA polymerase-mediated processive extension has revolutionized the field of whole genome amplification by enabling the amplification of minute amounts of DNA, such as from a single cell, generating vast amounts of DNA with high genome coverage. Despite its advantages, MDA has its own challenges, one of the grandest being the formation of chimeric sequences (chimeras), which presents in all MDA products and seriously disturbs the downstream analysis. In this review, we provide a comprehensive overview of current research on MDA chimeras. We first reviewed the mechanisms of chimera formation and chimera detection methods. We then systematically summarized the characteristics of chimeras, including overlap, chimeric distance, chimeric density, and chimeric rate, as found in independently published sequencing data. Finally, we reviewed the methods used to process chimeric sequences and their impacts on the improvement of data utilization efficiency. The information presented in this review will be useful for those interested in understanding the challenges with MDA and in improving its performance.
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Affiliation(s)
- Na Lu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Yi Qiao
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Zuhong Lu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Jing Tu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
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4
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Aoki H, Masahiro Y, Shimizu M, Hongoh Y, Ohkuma M, Yamagata Y. Agarose gel microcapsules enable easy-to-prepare, picolitre-scale, single-cell genomics, yielding high-coverage genome sequences. Sci Rep 2022; 12:17014. [PMID: 36257967 PMCID: PMC9579161 DOI: 10.1038/s41598-022-20923-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 09/21/2022] [Indexed: 12/29/2022] Open
Abstract
A novel type of agarose gel microcapsule (AGM), consisting of an alginate picolitre sol core and an agarose gel shell, was developed to obtain high-quality, single-cell, amplified genomic DNA of bacteria. The AGM is easy to prepare in a stable emulsion with oil of water-equivalent density, which prevents AGM aggregation, with only standard laboratory equipment. Single cells from a pure culture of Escherichia coli, a mock community comprising 15 strains of human gut bacteria, and a termite gut bacterial community were encapsulated within AGMs, and their genomic DNA samples were prepared with massively parallel amplifications in a tube. The genome sequencing did not need second-round amplification and showed an average genome completeness that was much higher than that obtained using a conventional amplification method on the microlitre scale, regardless of the genomic guanine-cytosine content. Our novel method using AGM will allow many researchers to perform single-cell genomics easily and effectively, and can accelerate genomic analysis of yet-uncultured microorganisms.
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Affiliation(s)
- Hiroyoshi Aoki
- grid.509457.aUltrahigh Precision Optics Technology Team, Advanced Photonics Technology Group, RIKEN Center for Advanced Photonics, 3-1, Hirosawa, Wako, Saitama 351-0198 Japan
| | - Yuki Masahiro
- grid.509462.cJapan Collection of Microorganisms (JCM), RIKEN BioResource Research Center, 3-1-1, Koyadai, Tsukuba, Ibaraki 305-0074 Japan
| | - Michiru Shimizu
- grid.509462.cJapan Collection of Microorganisms (JCM), RIKEN BioResource Research Center, 3-1-1, Koyadai, Tsukuba, Ibaraki 305-0074 Japan
| | - Yuichi Hongoh
- grid.509462.cJapan Collection of Microorganisms (JCM), RIKEN BioResource Research Center, 3-1-1, Koyadai, Tsukuba, Ibaraki 305-0074 Japan ,grid.32197.3e0000 0001 2179 2105School of Life Science and Technology, Tokyo Institute of Technology, Tokyo, Japan
| | - Moriya Ohkuma
- grid.509462.cJapan Collection of Microorganisms (JCM), RIKEN BioResource Research Center, 3-1-1, Koyadai, Tsukuba, Ibaraki 305-0074 Japan
| | - Yutaka Yamagata
- grid.509457.aUltrahigh Precision Optics Technology Team, Advanced Photonics Technology Group, RIKEN Center for Advanced Photonics, 3-1, Hirosawa, Wako, Saitama 351-0198 Japan
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5
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Gridina M, Taskina A, Lagunov T, Nurislamov A, Kulikova T, Krasikova A, Fishman V. Comparison and critical assessment of single-cell Hi-C protocols. Heliyon 2022; 8:e11023. [PMID: 36281413 PMCID: PMC9587272 DOI: 10.1016/j.heliyon.2022.e11023] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 08/13/2022] [Accepted: 10/06/2022] [Indexed: 01/24/2023] Open
Abstract
Advances in single-cell sequencing technologies make it possible to study the genome architecture in single cells. The rapid growth of the field has been fueled by the development of innovative single-cell Hi-C protocols. However, the protocols vary considerably in their efficiency, bias, scale and costs, and their relative advantages for different applications are unclear. Here, we compare the two most commonly used single-cell Hi-C protocols. We use long-read sequencing to analyze molecular products of the Hi-C assay and show that whole-genome amplification step results in increased number of artifacts, larger coverage biases, and increased amount of noise compared to PCR-based amplification. Our comparison provides guidance for researchers studying chromatin architecture in individual cells.
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6
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Lobo D, Linheiro R, Godinho R, Archer JP. On taming the effect of transcript level intra-condition count variation during differential expression analysis: A story of dogs, foxes and wolves. PLoS One 2022; 17:e0274591. [PMID: 36136981 PMCID: PMC9498955 DOI: 10.1371/journal.pone.0274591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 08/31/2022] [Indexed: 11/22/2022] Open
Abstract
The evolution of RNA-seq technologies has yielded datasets of scientific value that are often generated as condition associated biological replicates within expression studies. With expanding data archives opportunity arises to augment replicate numbers when conditions of interest overlap. Despite correction procedures for estimating transcript abundance, a source of ambiguity is transcript level intra-condition count variation; as indicated by disjointed results between analysis tools. We present TVscript, a tool that removes reference-based transcripts associated with intra-condition count variation above specified thresholds and we explore the effects of such variation on differential expression analysis. Initially iterative differential expression analysis involving simulated counts, where levels of intra-condition variation and sets of over represented transcripts are explicitly specified, was performed. Then counts derived from inter- and intra-study data representing brain samples of dogs, wolves and foxes (wolves vs. dogs and aggressive vs. tame foxes) were used. For simulations, the sensitivity in detecting differentially expressed transcripts increased after removing hyper-variable transcripts, although at levels of intra-condition variation above 5% detection became unreliable. For real data, prior to applying TVscript, ≈20% of the transcripts identified as being differentially expressed were associated with high levels of intra-condition variation, an over representation relative to the reference set. As transcripts harbouring such variation were removed pre-analysis, a discordance from 26 to 40% in the lists of differentially expressed transcripts is observed when compared to those obtained using the non-filtered reference. The removal of transcripts possessing intra-condition variation values within (and above) the 97th and 95th percentiles, for wolves vs. dogs and aggressive vs. tame foxes, maximized the sensitivity in detecting differentially expressed transcripts as a result of alterations within gene-wise dispersion estimates. Through analysis of our real data the support for seven genes with potential for being involved with selection for tameness is provided. TVscript is available at: https://sourceforge.net/projects/tvscript/.
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Affiliation(s)
- Diana Lobo
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Universidade do Porto, Vairão, Portugal
- BIOPOLIS, Program in Genomics, Biodiversity and Land Planning, CIBIO, Vairão, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
- * E-mail: (DL); (JPA)
| | - Raquel Linheiro
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Universidade do Porto, Vairão, Portugal
| | - Raquel Godinho
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Universidade do Porto, Vairão, Portugal
- BIOPOLIS, Program in Genomics, Biodiversity and Land Planning, CIBIO, Vairão, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
| | - John Patrick Archer
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Universidade do Porto, Vairão, Portugal
- BIOPOLIS, Program in Genomics, Biodiversity and Land Planning, CIBIO, Vairão, Portugal
- * E-mail: (DL); (JPA)
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7
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Nye DB, Tanner NA. Chimeric DNA byproducts in strand displacement amplification using the T7 replisome. PLoS One 2022; 17:e0273979. [PMID: 36121810 PMCID: PMC9484634 DOI: 10.1371/journal.pone.0273979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 08/19/2022] [Indexed: 11/30/2022] Open
Abstract
Recent advances in next generation sequencing technologies enable reading DNA molecules hundreds of kilobases in length and motivate development of DNA amplification methods capable of producing long amplicons. In vivo, DNA replication is performed not by a single polymerase enzyme, but multiprotein complexes called replisomes. Here, we investigate strand-displacement amplification reactions using the T7 replisome, a macromolecular complex of a helicase, a single-stranded DNA binding protein, and a DNA polymerase. The T7 replisome may initiate processive DNA synthesis from DNA nicks, and the reaction of a 48 kilobase linear double stranded DNA substrate with the T7 replisome and nicking endonucleases is shown to produce discrete DNA amplicons. To gain a mechanistic understanding of this reaction, we utilized Oxford Nanopore long-read sequencing technology. Sequence analysis of the amplicons revealed chimeric DNA reads and uncovered a connection between template switching and polymerase exonuclease activity. Nanopore sequencing provides insight to guide the further development of isothermal amplification methods for long DNA, and our results highlight the need for high-specificity, high-turnover nicking endonucleases to initiate DNA amplification without thermal denaturation.
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Affiliation(s)
- Dillon B. Nye
- Nucleic Acid Replication Division, New England Biolabs Inc., Ipswich, Massachusetts, United States of America
| | - Nathan A. Tanner
- Nucleic Acid Replication Division, New England Biolabs Inc., Ipswich, Massachusetts, United States of America
- * E-mail:
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8
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Wang W, Chen Y, Wu L, Zhang Y, Yoo S, Chen Q, Liu S, Hou Y, Chen XP, Chen Q, Zhu J. HBV genome-enriched single cell sequencing revealed heterogeneity in HBV-driven hepatocellular carcinoma (HCC). BMC Med Genomics 2022; 15:134. [PMID: 35710421 PMCID: PMC9205089 DOI: 10.1186/s12920-022-01264-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 05/05/2022] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Hepatitis B virus (HBV) related hepatocellular carcinoma (HCC) is heterogeneous and frequently contains multifocal tumors, but how the multifocal tumors relate to each other in terms of HBV integration and other genomic patterns is not clear. METHODS To interrogate heterogeneity of HBV-HCC, we developed a HBV genome enriched single cell sequencing (HGE-scSeq) procedure and a computational method to identify HBV integration sites and infer DNA copy number variations (CNVs). RESULTS We performed HGE-scSeq on 269 cells from four tumor sites and two tumor thrombi of a HBV-HCC patient. HBV integrations were identified in 142 out of 269 (53%) cells sequenced, and were enriched in two HBV integration hotspots chr1:34,397,059 (CSMD2) and chr8:118,557,327 (MED30/EXT1). There were also 162 rare integration sites. HBV integration sites were enriched in DNA fragile sites and sequences around HBV integration sites were enriched for microhomologous sequences between human and HBV genomes. CNVs were inferred for each individual cell and cells were grouped into four clonal groups based on their CNVs. Cells in different clonal groups had different degrees of HBV integration heterogeneity. All of 269 cells carried chromosome 1q amplification, a recurrent feature of HCC tumors, suggesting that 1q amplification occurred before HBV integration events in this case study. Further, we performed simulation studies to demonstrate that the sequential events (HBV infecting transformed cells) could result in the observed phenotype with biologically reasonable parameters. CONCLUSION Our HGE-scSeq data reveals high heterogeneity of HCC tumor cells in terms of both HBV integrations and CNVs. There were two HBV integration hotspots across cells, and cells from multiple tumor sites shared some HBV integration and CNV patterns.
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Affiliation(s)
- Wenhui Wang
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Ave., New York, NY, 10029, USA
- Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Sema4, Stamford, CT, USA
| | - Yan Chen
- The Hepatic Surgery Centre at Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China
| | | | - Yi Zhang
- Department of Mathematics, Hebei University of Science and Technology, Shijiazhuang, Hebei, China
| | - Seungyeul Yoo
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Ave., New York, NY, 10029, USA
- Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Sema4, Stamford, CT, USA
| | - Quan Chen
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Ave., New York, NY, 10029, USA
- Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Sema4, Stamford, CT, USA
| | | | | | - Xiao-Ping Chen
- The Hepatic Surgery Centre at Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China
| | - Qian Chen
- The Division of Gastroenterology, Department of Internal Medicine at Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.
| | - Jun Zhu
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Ave., New York, NY, 10029, USA.
- Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Sema4, Stamford, CT, USA.
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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Zhang Z, An HH, Vege S, Hu T, Zhang S, Mosbruger T, Jayaraman P, Monos D, Westhoff CM, Chou ST. Accurate long-read sequencing allows assembly of the duplicated RHD and RHCE genes harboring variants relevant to blood transfusion. Am J Hum Genet 2022; 109:180-191. [PMID: 34968422 DOI: 10.1016/j.ajhg.2021.12.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 12/07/2021] [Indexed: 12/18/2022] Open
Abstract
Next-generation sequencing (NGS) technologies have transformed medical genetics. However, short-read lengths pose a limitation on identification of structural variants, sequencing repetitive regions, phasing of distant nucleotide changes, and distinguishing highly homologous genomic regions. Long-read sequencing technologies may offer improvements in the characterization of genes that are currently difficult to assess. We used a combination of targeted DNA capture, long-read sequencing, and a customized bioinformatics pipeline to fully assemble the RH region, which harbors variation relevant to red cell donor-recipient mismatch, particularly among patients with sickle cell disease. RHD and RHCE are a pair of duplicated genes located within an ∼175 kb region on human chromosome 1 that have high sequence similarity and frequent structural variations. To achieve the assembly, we utilized palindrome repeats in PacBio SMRT reads to obtain consensus sequences of 2.1 to 2.9 kb average length with over 99% accuracy. We used these long consensus sequences to identify 771 assembly markers and to phase the RHD-RHCE region with high confidence. The dataset enabled direct linkage between coding and intronic variants, phasing of distant SNPs to determine RHD-RHCE haplotypes, and identification of known and novel structural variations along with the breakpoints. A limiting factor in phasing is the frequency of heterozygous assembly markers and therefore was most successful in samples from African Black individuals with increased heterogeneity at the RH locus. Overall, this approach allows RH genotyping and de novo assembly in an unbiased and comprehensive manner that is necessary to expand application of NGS technology to high-resolution RH typing.
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Affiliation(s)
- Zhe Zhang
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Hyun Hyung An
- Division of Hematology, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Sunitha Vege
- Immunohematology and Genomics, New York Blood Center, New York, NY 11101, USA
| | - Taishan Hu
- Immunogenetics Laboratory, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Shiping Zhang
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Timothy Mosbruger
- Immunogenetics Laboratory, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Pushkala Jayaraman
- Immunogenetics Laboratory, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Dimitri Monos
- Immunogenetics Laboratory, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; Department of Pathology and Laboratory Medicine, Perelman Schools of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Connie M Westhoff
- Immunohematology and Genomics, New York Blood Center, New York, NY 11101, USA
| | - Stella T Chou
- Division of Hematology, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; Division of Transfusion Medicine, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
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10
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CStone: A de novo transcriptome assembler for short-read data that identifies non-chimeric contigs based on underlying graph structure. PLoS Comput Biol 2021; 17:e1009631. [PMID: 34813594 PMCID: PMC8651127 DOI: 10.1371/journal.pcbi.1009631] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 12/07/2021] [Accepted: 11/11/2021] [Indexed: 11/19/2022] Open
Abstract
With the exponential growth of sequence information stored over the last decade, including that of de novo assembled contigs from RNA-Seq experiments, quantification of chimeric sequences has become essential when assembling read data. In transcriptomics, de novo assembled chimeras can closely resemble underlying transcripts, but patterns such as those seen between co-evolving sites, or mapped read counts, become obscured. We have created a de Bruijn based de novo assembler for RNA-Seq data that utilizes a classification system to describe the complexity of underlying graphs from which contigs are created. Each contig is labelled with one of three levels, indicating whether or not ambiguous paths exist. A by-product of this is information on the range of complexity of the underlying gene families present. As a demonstration of CStones ability to assemble high-quality contigs, and to label them in this manner, both simulated and real data were used. For simulated data, ten million read pairs were generated from cDNA libraries representing four species, Drosophila melanogaster, Panthera pardus, Rattus norvegicus and Serinus canaria. These were assembled using CStone, Trinity and rnaSPAdes; the latter two being high-quality, well established, de novo assembers. For real data, two RNA-Seq datasets, each consisting of ≈30 million read pairs, representing two adult D. melanogaster whole-body samples were used. The contigs that CStone produced were comparable in quality to those of Trinity and rnaSPAdes in terms of length, sequence identity of aligned regions and the range of cDNA transcripts represented, whilst providing additional information on chimerism. Here we describe the details of CStones assembly and classification process, and propose that similar classification systems can be incorporated into other de novo assembly tools. Within a related side study, we explore the effects that chimera’s within reference sets have on the identification of differentially expression genes. CStone is available at: https://sourceforge.net/projects/cstone/. Within transcriptome reference sets, non-chimeric sequences are representations of transcribed genes, while artificially generated chimeric ones are mosaics of two or more pieces of DNA incorrectly pieced together. One area where such sets are utilized is in the quantification of gene expression patterns; where RNA-Seq reads are mapped to the sequences within, and subsequent count values reflect expression levels. Artificial chimeras can have a negative impact on count values by erroneously increasing variation in relation to the reads being mapped. Reference sets can be created from de novo assembled contigs, but chimeras can be introduced during the assembly process via the required traversal of graphs, representing gene families, constructed from the RNA-Seq data. Graph complexity determines how likely chimeras will arise. We have created CStone, a de novo assembler that utilizes a classification system to describe such complexity. Contigs created by CStone are labelled in a manner that indicates whether or not they are non-chimeric. This encourages contig dependent results to be presented with increased objectivity by maintaining the context of ambiguity associated with the assembly process. CStone has been tested extensively. Additionally, we have quantified the relationship between chimeras within reference sets and the identification of differentially expressed genes.
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Kiguchi Y, Nishijima S, Kumar N, Hattori M, Suda W. Long-read metagenomics of multiple displacement amplified DNA of low-biomass human gut phageomes by SACRA pre-processing chimeric reads. DNA Res 2021; 28:6377780. [PMID: 34586399 DOI: 10.1093/dnares/dsab019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Indexed: 01/21/2023] Open
Abstract
The human gut bacteriophage community (phageome) plays an important role in the host's health and disease; however, the entire structure is poorly understood, partly owing to the generation of many incomplete genomes in conventional short-read metagenomics. Here, we show long-read metagenomics of amplified DNA of low-biomass phageomes with multiple displacement amplification (MDA), involving the development of a novel bioinformatics tool, split amplified chimeric read algorithm (SACRA), that efficiently pre-processed numerous chimeric reads generated through MDA. Using five samples, SACRA markedly reduced the average chimera ratio from 72% to 1.5% in PacBio reads with an average length of 1.8 kb. De novo assembly of chimera-less PacBio long reads reconstructed contigs of ≥5 kb with an average proportion of 27%, which was 1% in contigs from MiSeq short reads, thereby dramatically improving contig length and genome completeness. Comparison of PacBio and MiSeq contigs found MiSeq contig fragmentations frequently near local repeats and hypervariable regions in the phage genomes, and those caused by multiple homologous phage genomes coexisting in the community. We also developed a reference-independent method to assess the completeness of the linear phage genomes. Overall, we established a SACRA-coupled long-read metagenomics robust to highly diverse gut phageomes, identifying high-quality circular and linear phage genomes with adequate sequence quantity.
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Affiliation(s)
- Yuya Kiguchi
- Cooperative Major in Advanced Health Science, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo 169-8555, Japan
- Computational Bio Big-Data Open Innovation Laboratory (CBBD-OIL), National Institute of Advanced Industrial Science and Technology, Tokyo 169-8555, Japan
- Laboratory for Microbiome Sciences, RIKEN Center for Integrative Medical Sciences, Yokohama 230-0045, Japan
| | - Suguru Nishijima
- Computational Bio Big-Data Open Innovation Laboratory (CBBD-OIL), National Institute of Advanced Industrial Science and Technology, Tokyo 169-8555, Japan
- Integrated Institute for Regulatory Science, Waseda University, Tokyo 169-8555, Japan
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Naveen Kumar
- Laboratory for Microbiome Sciences, RIKEN Center for Integrative Medical Sciences, Yokohama 230-0045, Japan
| | - Masahira Hattori
- Cooperative Major in Advanced Health Science, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo 169-8555, Japan
- Laboratory for Microbiome Sciences, RIKEN Center for Integrative Medical Sciences, Yokohama 230-0045, Japan
| | - Wataru Suda
- Laboratory for Microbiome Sciences, RIKEN Center for Integrative Medical Sciences, Yokohama 230-0045, Japan
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mtDNA Heteroplasmy: Origin, Detection, Significance, and Evolutionary Consequences. Life (Basel) 2021; 11:life11070633. [PMID: 34209862 PMCID: PMC8307225 DOI: 10.3390/life11070633] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 06/24/2021] [Indexed: 12/11/2022] Open
Abstract
Mitochondrial DNA (mtDNA) is predominately uniparentally transmitted. This results in organisms with a single type of mtDNA (homoplasmy), but two or more mtDNA haplotypes have been observed in low frequency in several species (heteroplasmy). In this review, we aim to highlight several aspects of heteroplasmy regarding its origin and its significance on mtDNA function and evolution, which has been progressively recognized in the last several years. Heteroplasmic organisms commonly occur through somatic mutations during an individual’s lifetime. They also occur due to leakage of paternal mtDNA, which rarely happens during fertilization. Alternatively, heteroplasmy can be potentially inherited maternally if an egg is already heteroplasmic. Recent advances in sequencing techniques have increased the ability to detect and quantify heteroplasmy and have revealed that mitochondrial DNA copies in the nucleus (NUMTs) can imitate true heteroplasmy. Heteroplasmy can have significant evolutionary consequences on the survival of mtDNA from the accumulation of deleterious mutations and for its coevolution with the nuclear genome. Particularly in humans, heteroplasmy plays an important role in the emergence of mitochondrial diseases and determines the success of the mitochondrial replacement therapy, a recent method that has been developed to cure mitochondrial diseases.
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Dhorne-Pollet S, Barrey E, Pollet N. A new method for long-read sequencing of animal mitochondrial genomes: application to the identification of equine mitochondrial DNA variants. BMC Genomics 2020; 21:785. [PMID: 33176683 PMCID: PMC7661214 DOI: 10.1186/s12864-020-07183-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 10/26/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Mitochondrial DNA is remarkably polymorphic. This is why animal geneticists survey mitochondrial genomes variations for fundamental and applied purposes. We present here an approach to sequence whole mitochondrial genomes using nanopore long-read sequencing. Our method relies on the selective elimination of nuclear DNA using an exonuclease treatment and on the amplification of circular mitochondrial DNA using a multiple displacement amplification step. RESULTS We optimized each preparative step to obtain a 100 million-fold enrichment of horse mitochondrial DNA relative to nuclear DNA. We sequenced these amplified mitochondrial DNA using nanopore sequencing technology and obtained mitochondrial DNA reads that represented up to half of the sequencing output. The sequence reads were 2.3 kb of mean length and provided an even coverage of the mitochondrial genome. Long-reads spanning half or more of the whole mtDNA provided a coverage that varied between 118X and 488X. We evaluated SNPs identified using these long-reads by Sanger sequencing as ground truth and found a precision of 100.0%; a recall of 93.1% and a F1-score of 0.964 using the Twilight horse mtDNA reference. The choice of the mtDNA reference impacted variant calling efficiency with F1-scores varying between 0.947 and 0.964. CONCLUSIONS Our method to amplify mtDNA and to sequence it using the nanopore technology is usable for mitochondrial DNA variant analysis. With minor modifications, this approach could easily be applied to other large circular DNA molecules.
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Affiliation(s)
- Sophie Dhorne-Pollet
- Université Paris-Saclay, INRAE, AgroParisTech, GABI, 78350, Jouy-en-Josas, France
| | - Eric Barrey
- Université Paris-Saclay, INRAE, AgroParisTech, GABI, 78350, Jouy-en-Josas, France
| | - Nicolas Pollet
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198, Gif-sur-Yvette, France.
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De novo sequence assembly requires bioinformatic checking of chimeric sequences. PLoS One 2020; 15:e0237455. [PMID: 32777809 PMCID: PMC7417191 DOI: 10.1371/journal.pone.0237455] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 07/27/2020] [Indexed: 11/24/2022] Open
Abstract
De novo assembly of sequence reads from next generation sequencing platforms is a common strategy for detecting presence and sequencing of viruses in biospecimens. Amplification artifacts and presence of several related viruses in the same specimen can lead to assembly of erroneous, chimeric sequences. We now report that such chimeras can also occur between viral and non-viral biological sequences incorrectly joined together which may cause erroneous detection of viruses, highlighting the importance of performing a chimera checking step in bioinformatics pipelines. Using Illumina NextSeq and metagenomic sequencing, we analyzed 80 consecutive non-melanoma skin cancers (NMSCs) from 11 immunosuppressed patients together with 11 NMSCs from patients who had only developed 1 NMSC. We aligned high-quality reads against a Human Papillomavirus (HPV) database and found HPV sequences in 9/91 specimens. A previous bioinformatic analysis of the same crude sequencing data from some of these samples had found an additional 3 specimens to be HPV-positive after performing de novo assembly. The reason for the discrepancy was investigated and found to be mostly caused by chimeric sequences containing both viral and non-viral sequences. Non-viral sequences were present in these 3 samples. To avoid erroneous detection of HPV when performing sequencing, we thus developed a novel script to identify HPV chimeric sequences.
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ChimeraMiner: An Improved Chimeric Read Detection Pipeline and Its Application in Single Cell Sequencing. Int J Mol Sci 2019; 20:ijms20081953. [PMID: 31010074 PMCID: PMC6515389 DOI: 10.3390/ijms20081953] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 04/15/2019] [Accepted: 04/19/2019] [Indexed: 01/09/2023] Open
Abstract
As the most widely-used single cell whole genome amplification (WGA) approach, multiple displacement amplification (MDA) has a superior performance, due to the high-fidelity and processivity of phi29 DNA polymerase. However, chimeric reads, generated in MDA, cause severe disruption in many single-cell studies. Herein, we constructed ChimeraMiner, an improved chimeric read detection pipeline for analyzing the sequencing data of MDA and classified the chimeric sequences. Two datasets (MDA1 and MDA2) were used for evaluating and comparing the efficiency of ChimeraMiner and previous pipeline. Under the same hardware condition, ChimeraMiner spent only 43.4% (43.8% for MDA1 and 43.0% for MDA2) processing time. Respectively, 24.4 million (6.31%) read pairs out of 773 million reads, and 17.5 million (6.62%) read pairs out of 528 million reads were accurately classified as chimeras by ChimeraMiner. In addition to finding 83.60% (17,639,371) chimeras, which were detected by previous pipelines, ChimeraMiner screened 6,736,168 novel chimeras, most of which were missed by the previous pipeline. Applying in single-cell datasets, all three types of chimera were discovered in each dataset, which introduced plenty of false positives in structural variation (SV) detection. The identification and filtration of chimeras by ChimeraMiner removed most of the false positive SVs (83.8%). ChimeraMiner revealed improved efficiency in discovering chimeric reads, and is promising to be widely used in single-cell sequencing.
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Zhao L, Rosario K, Breitbart M, Duffy S. Eukaryotic Circular Rep-Encoding Single-Stranded DNA (CRESS DNA) Viruses: Ubiquitous Viruses With Small Genomes and a Diverse Host Range. Adv Virus Res 2018; 103:71-133. [PMID: 30635078 DOI: 10.1016/bs.aivir.2018.10.001] [Citation(s) in RCA: 127] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
While single-stranded DNA (ssDNA) was once thought to be a relatively rare genomic architecture for viruses, modern metagenomics sequencing has revealed circular ssDNA viruses in most environments and in association with diverse hosts. In particular, circular ssDNA viruses encoding a homologous replication-associated protein (Rep) have been identified in the majority of eukaryotic supergroups, generating interest in the ecological effects and evolutionary history of circular Rep-encoding ssDNA viruses (CRESS DNA) viruses. This review surveys the explosion of sequence diversity and expansion of eukaryotic CRESS DNA taxonomic groups over the last decade, highlights similarities between the well-studied geminiviruses and circoviruses with newly identified groups known only through their genome sequences, discusses the ecology and evolution of eukaryotic CRESS DNA viruses, and speculates on future research horizons.
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Affiliation(s)
- Lele Zhao
- Department of Ecology, Evolution and Natural Resources, Rutgers, the State University of New Jersey, New Brunswick, NJ, United States
| | - Karyna Rosario
- College of Marine Science, University of South Florida, Saint Petersburg, FL, United States
| | - Mya Breitbart
- College of Marine Science, University of South Florida, Saint Petersburg, FL, United States
| | - Siobain Duffy
- Department of Ecology, Evolution and Natural Resources, Rutgers, the State University of New Jersey, New Brunswick, NJ, United States.
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Boone M, De Koker A, Callewaert N. Capturing the 'ome': the expanding molecular toolbox for RNA and DNA library construction. Nucleic Acids Res 2018; 46:2701-2721. [PMID: 29514322 PMCID: PMC5888575 DOI: 10.1093/nar/gky167] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Revised: 02/05/2018] [Accepted: 02/23/2018] [Indexed: 12/14/2022] Open
Abstract
All sequencing experiments and most functional genomics screens rely on the generation of libraries to comprehensively capture pools of targeted sequences. In the past decade especially, driven by the progress in the field of massively parallel sequencing, numerous studies have comprehensively assessed the impact of particular manipulations on library complexity and quality, and characterized the activities and specificities of several key enzymes used in library construction. Fortunately, careful protocol design and reagent choice can substantially mitigate many of these biases, and enable reliable representation of sequences in libraries. This review aims to guide the reader through the vast expanse of literature on the subject to promote informed library generation, independent of the application.
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Affiliation(s)
- Morgane Boone
- Center for Medical Biotechnology, VIB, Zwijnaarde 9052, Belgium
- Department of Biochemistry and Microbiology, Ghent University, Ghent 9000, Belgium
| | - Andries De Koker
- Center for Medical Biotechnology, VIB, Zwijnaarde 9052, Belgium
- Department of Biochemistry and Microbiology, Ghent University, Ghent 9000, Belgium
| | - Nico Callewaert
- Center for Medical Biotechnology, VIB, Zwijnaarde 9052, Belgium
- Department of Biochemistry and Microbiology, Ghent University, Ghent 9000, Belgium
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Hotspot Selective Preference of the Chimeric Sequences Formed in Multiple Displacement Amplification. Int J Mol Sci 2017; 18:ijms18030492. [PMID: 28245591 PMCID: PMC5372508 DOI: 10.3390/ijms18030492] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Revised: 02/16/2017] [Accepted: 02/20/2017] [Indexed: 01/01/2023] Open
Abstract
Multiple displacement amplification (MDA) is considered to be a conventional approach to comprehensive amplification from low input DNA. The chimeric reads generated in MDA lead to severe disruption in some studies, including those focusing on heterogeneity, structural variation, and genetic recombination. Meanwhile, the generation of by-products gives a new approach to gain insights into the reaction process of φ29 polymerase. Here, we analyzed 36.7 million chimeras and screened 196 billion chimeric hotspots in the human genome, as well as evaluating the hotspot selective preference of chimeras. No significant preference was captured in the distributions of chimeras and hotspots among chromosomes. Hotspots with overlaps for 12–13 nucleotides (nt) were most likely to be selected as templates in chimera generation. Meanwhile, a regularly selective preference was noticed in overlap GC content. The preferences in overlap length and GC content was shown to be pertinent to the sequence denaturation temperature, which pointed out the optimization direction for reducing chimeras. Distance preference between two segments of chimeras was 80–280 nt. The analysis is beneficial for reducing the chimeras in MDA, and the characterization of MDA chimeras is helpful in distinguishing MDA chimeras from chimeric sequences caused by disease.
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