Advertisement

Development and strategy of reference materials for the DNA-based detection of genetically modified organisms

  • Yuhua Wu
  • Jun Li
  • Xiaying Li
  • Shanshan Zhai
  • Hongfei Gao
  • Yunjing Li
  • Xiujie ZhangEmail author
  • Gang WuEmail author
Review
  • 26 Downloads

Abstract

The enforcement of GMO labeling regulations requires validated analytical methods and certified reference materials (CRMs). The early labeling regulations stipulated that the GMO content should be expressed as percentage, but did not specify what unit this percentage referred to. Two reference systems, using mass fraction and copy number ratio as measurement units, individually, are established for GMO analysis using different metrological traceability chains. Three types of CRMs, powder CRMs certified for mass fractions, genomic DNA CRMs, and plasmid DNA CRMs certified for copy number ratios, were developed for calibration and quality control. The type, certification, and measurement unit commutability of current GMO CRMs are presented and discussed in this paper. Both existing reference systems are facing a metrological challenge, although later EU regulations specified that the measurement unit of GMO content must be expressed in mass fraction and recommended to convert one unit into another by introducing a conversion factor, further efforts are required to explore which reference system is more metrologically sound. The determination of conversion factor per CRM batch is recommended to be based on the pure CRMs produced from pure GM materials, which is expected to be the best choice for calibration of PCR measurement results.

Keywords

GMO PCR Reference materials Measurement unit Mass fraction Copy number ratio 

Notes

Acknowledgments

We would like to thank LetPub (www.letpub.com) for providing linguistic assistance during the preparation of this manuscript.

Funding information

This paper was supported by grants from the National Major Special Project for the Development of Transgenic Organisms (grant no. 2016ZX08012-003) and the project of National Natural Science Foundation of China (grant no. 31601581).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

References

  1. 1.
    Davison J, Bertheau Y. EU regulation on the traceability and detection of GMOs: difficulties in interpretation, implementation and compliance. CAB review 2. 2007; No. 077.Google Scholar
  2. 2.
    Gruere GP, Rao SR. A review of international labeling policies of genetically modifi ed food to evaluate India’s proposed rule. AgBioForum. 2007;10:51–64.Google Scholar
  3. 3.
    Lauwaars M, Anklam E. Method validation and reference materials. Accred Qual Assur. 2004;9:253–8.CrossRefGoogle Scholar
  4. 4.
    Trapmann S, Corbisier P, Schimmel H, Emons H. Towards future reference systems for GM analysis. Anal Bioanal Chem. 2010;396:1969–75.CrossRefGoogle Scholar
  5. 5.
    Trapmann S, Emons H. Reliable GMO analysis. Anal Bioanal Chem. 2005;381:72–4.CrossRefGoogle Scholar
  6. 6.
    Holst-Jensen A, Berdal KG. The modular analytical procedure and validation approach and the units of measurement for genetically modified materials in foods and feeds. J AOAC Int. 2004;87(4):927–36.Google Scholar
  7. 7.
    Kay S, Van den Eede G. The limits of GMO detection. Nat Biotechnol. 2001;19:405.CrossRefGoogle Scholar
  8. 8.
    Regulation (EC) No 1830/2003 of the European Parliament and of the Council of 22 September 2003 concerning the traceability and labelling of genetically modified organisms and the traceability of food and feed products produced from genetically modified organisms and amending Directive 2001/18/EC (2003). Official Journal of the European Union L: 24–28.Google Scholar
  9. 9.
    European Commission (2004) Recommendation 2004/787/EC: Commission Recommendation of 4 October 2004 on technical guidance for sampling and detection of genetically modified organisms and material produced from genetically modified organisms as or in products in the context of Regulation (EC) No 1830/2003. Official Journal of the European Union L. 2004; 348:18–26.Google Scholar
  10. 10.
    Chaouachi M, Be’rard A, Saïd K. Relative quantification in seed GMO analysis: state of art and bottlenecks. Transgenic Res. 2013;22:461–76.CrossRefGoogle Scholar
  11. 11.
    Holst-Jensen A, De Loose M, Van den Eede G. Coherence between legal requirements and approaches for detection of genetically modified organisms (GMO) and their derived products. J Agric Food Chem. 2006;54(8):2799–809.CrossRefGoogle Scholar
  12. 12.
    European Commission. Commission Regulation (EU) No 619/2011 of 24 June 2011 laying down the methods of sampling and analysis for the official control of feed as regards presence of genetically modified material for which an authorisation procedure is pending or the authorization of which has expired. Off J Eur Union. 2011;L166:9–13.Google Scholar
  13. 13.
    European Commission (2017) Recommendation for the unit of measurement and the measuring system to report traceable and comparable results expressing GM content in accordance with EU legislation. JRC technical reports. JRC106032. Publications Office of the European Union. 2017; 1–32.Google Scholar
  14. 14.
    Hernandez M, Rodrıguez-Lazaro D, Ferrando A. Current methodology for detection, identification and quantification of genetically modified organisms. Curr Anal Chem. 2012;1(2):203–21.CrossRefGoogle Scholar
  15. 15.
    Holst-Jensen A. Testing for genetically modified organisms (GMOs): past, present and future perspectives. Biotechnol Adv. 2009;27:1071–82.CrossRefGoogle Scholar
  16. 16.
    Lipp M, Shillito R, Giroux R, Spiegelhalter F, Charlton S, Pinero D, et al. Polymerase chain reaction technology as analytical tool in agricultural biotechnology. J AOAC Int. 2005;88(1):136–55.Google Scholar
  17. 17.
    Miraglia M, Berdal KG, Brera C, Corbisier P, Holst-Jensen A, Kok EJ, Marvin HJ, Schimmel H, Rentsch J, van Rie JP, Zagon J. Detection and traceability of genetically modified organisms in the food production chain. Food Chem Toxicol 2004 42(7): 1157–80.Google Scholar
  18. 18.
    Holst-Jensen A, Ronning SB, Lovseth A, Berdal KG. PCR technology for screening and quantification of genetically modified organisms (GMOs). Anal Bioanal Chem. 2003;375:985–93.CrossRefGoogle Scholar
  19. 19.
    Zel J, Milavec M, Morisset D, Plan D, Van den Eede G, Gruden K. How to Reliably Test for GMOs. SpringerBriefs in Food, Health, and Nutrition. 2012;  https://doi.org/10.1007/978-1-4614-1390-5_1. http://www.springer.com/978-1-4614-1389-9
  20. 20.
    Bustin S, Benes V, Garson J, Hellemans J, Huggett J, Kubista M, et al. The MIQE guidelines: minimum information for publication of quantitative real-time PCR experiments. Clin Chem. 2009;55:611–22.CrossRefGoogle Scholar
  21. 21.
    European Commission (2015) Definition of Minimum Performance Requirements for Analytical Methods of GMO Testing. http://gmo-crl.jrc.ec.europa.eu/doc/MPR%20Report%20Application%2020_10_2015.pdf. Accessed April 2018.
  22. 22.
    Anklam E, Neumann N. Method development in relation to regulatory requirements for detection of GMOs in the food chain. J AOAC Int. 2002;86:754–6.Google Scholar
  23. 23.
    Allnutt T, Chisholm J, Hird H, Oehlschlager S, Henry C. Final Report Plasmid Standards for Real Time PCR and GM Enforcement Testing. 2017; http://webarchive.nationalarchives.gov.uk/20141103164952/http://www.gm-inspectorate.gov.uk/documents/PLASMID.pdf. Accessed 15 Dec 2017.
  24. 24.
    Heid CA, Stevens J, Livak KJ, Williams PM. Real time quantitative PCR. Genome Res. 1996;6(10):986–94.CrossRefGoogle Scholar
  25. 25.
    Livak KJ, Schmittgen TD. Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta Delta C(T)) Method. Methods. 2001;25(4):402–8.CrossRefGoogle Scholar
  26. 26.
    EU-RL GMFF. Event-specific method for the quantification of maize event Bt11 using real-time PCR – Validation Report and Protocol. 2008; https://publications.europa.eu/portal2012-portlet/html/downloadHandler.jsp?identifier=3ef88217-7fc5-4cc7-a56e-7dc8a93b1014&format=pdf&language=en&productionSystem=cellar&part=. Accessed 15 Dec 2017.
  27. 27.
    EU-RL GMFF. Event-specific method for the quantification of soybean line A2704-12 using real-time PCR protocol. 2007; https://publications.europa.eu/portal2012-portlet/html/downloadHandler.jsp?identifier=6b7608cb-c668-4bdb-86c3-f8c9917ab89d&format=pdfx&language=en&productionSystem=cellar&part=. Accessed 15 Dec 2017.
  28. 28.
    Wei J, Le H, Pan A, Xu J, Li F, Li X, et al. Collaborative trial for the validation of event-specific PCR detection methods of genetically modified papaya Huanong No.1. Food Chem. 2016;194:20–5.CrossRefGoogle Scholar
  29. 29.
    Jacchia S, Nardini E, Bassani N, Savini C, Shim JH, Trijatmiko K, et al. International ring trial for the validation of an event-specific Golden Rice 2 quantitative real-time polymerase chain reaction method. J Agric Food Chem. 2015;63(20):4954–65.CrossRefGoogle Scholar
  30. 30.
    Wu Y, Yang L, Cao Y, Song G, Shen P, Zhang D, et al. Collaborative validation of an event-specific quantitative real-time PCR method for genetically modified rice event TT51-1 detection. J Agric Food Chem J. 2013;61(25):5953–60.CrossRefGoogle Scholar
  31. 31.
    Caprioara-Buda M, Meyer W, Jeynov B, Corbisier P, Trapmann, Emons H. Evaluation of plasmid and genomic DNA calibrants used for the quantification of genetically modified organisms. Anal Bioanal Chem. 2012;404:29–42.CrossRefGoogle Scholar
  32. 32.
    Basic and general concepts and associated terms (VIM). ISO/IEC Guide. 2007;99:2007.Google Scholar
  33. 33.
    Treml D, Venturelli DL, Brod FC, Faria JC, Aris AC. Development of an event-specific hydrolysis probe quantitative real-time polymerase chain reaction assay for Embrapa 5.1 genetically modified common bean (Phaseolus vulgaris). J Agric Food Chem 2014; 62, 11994–12000.Google Scholar
  34. 34.
    Babekova R, Funk T, Pecoraro S, Engel KH, Busch U. Development of an event-specifc real-time PCR detection method for the transgenic Bt rice line KMD1. Eur Food Res Technol. 2009;228:707–16.CrossRefGoogle Scholar
  35. 35.
    Wu G, Wu YH, Nie SJ, Zhang L, Xiao L, Cao YL, et al. Real-time PCR method for detection of the transgenic rice event TT51-1. Food Chem. 2010;119:417–22.CrossRefGoogle Scholar
  36. 36.
    Wu YH, Wu G, Xiao L, Lu CM. Event-specific qualitative and quantitative PCR detection for transgenic rapeseed hybrids MS1×RF1 and MS1×RF2. J Agric Food Chem. 2007;55(21):8380–9.CrossRefGoogle Scholar
  37. 37.
    Yang L, Xu S, Pan A, Yin C, Zhang K, Wang Z, et al. Event specific qualitative and quantitative polymerase chain reaction detection of genetically modified MON863 maize based on the 5′-transgene integration sequence. J Agric Food Chem. 2005;53(24):9312–8.CrossRefGoogle Scholar
  38. 38.
    Lindahl T. Instability and decay of the primary structure of DNA. Nature 1993; 362 (6422): 709–715.Google Scholar
  39. 39.
    Lee SB, Crouse CA, Kline MC. Optimizing storage and handling of DNA extracts. Forensic Sci Rev. 2010;22:131–44.Google Scholar
  40. 40.
    Gryson N. Effect of food processing on plant DNA degradation and PCR-based GMO analysis: a review. Anal Bioanal Chem. 2010;396:2003–22.CrossRefGoogle Scholar
  41. 41.
    Bonnet J, Colotte M, Coudy D, Couallier V, Portier J, Morin B, et al. Chain and conformation stability of solid state DNA: implications for room temperature storage. Nucleic Acids Res. 2010;38:1531–46.CrossRefGoogle Scholar
  42. 42.
    Clermont D, Santoni S, Saker S, Gomard M, Gardais E, Bizet C. Assessment of DNA encapsulation, a new room-temperature DNA storage method. Biopreserv Biobank 2014;12(3):176–83.Google Scholar
  43. 43.
    Taverniers I, Windels P, Bockstaele EV, Loose MD. Use of cloned DNA fragments for event-specific quantification of genetically modified organisms in pure and mixed food products. Eur Food Res Technol. 2001;213:417–24.CrossRefGoogle Scholar
  44. 44.
    Taverniers I, Van Bockstaele E, De Loose M. Cloned plasmid DNA fragments as calibrators for controlling GMOs: different real-time duplex quantitative PCR methods. Anal Bioanal Chem. 2004;378:1198–207.CrossRefGoogle Scholar
  45. 45.
    Certification report: Certification of plasmidic DNA containing MON 810 maize DNA fragments, Certified Reference Materials ERM®-AD413. EUR 22948 EN, ISBN 978-92-79-07139-3, ISSN 1018-5593.  https://doi.org/10.2787/49996. Luxembourg: Office for Official Publications of the European Communities, © European Communities, 2007.
  46. 46.
    Certification report: Certification of plasmid DNA containing 98140 Maize DNA fragments, Certified Reference Material ERM®-BF427. EUR 24722 EN, ISBN 978-92-79-19277-7, ISSN 1018-5593.  https://doi.org/10.2787/38563. Luxembourg: Publications Office of the European Union, © European Union, 2011.
  47. 47.
    Certification report: Certification of plasmid DNA containing NK603 maize DNA fragments, Certified Reference Materials ERM®-AD415. EUR 24696 EN, ISBN 978-92-79-19071-1, ISSN 1018-5593.  https://doi.org/10.2787/37591. Luxembourg: Publications Office of the European Union, © European Union, 2011.
  48. 48.
    Certification report: Certification of plasmid DNA containing 356043 Soybean DNA fragments, Certified Reference Materials ERM®-AD425. EUR 24687 EN, ISBN 978-92-79-18997-7, ISSN 1018-5593.  https://doi.org/10.2787/36019. Luxembourg: Publications Office of the European Union, © European Union, 2011.
  49. 49.
    Zhang L, Wu YH, Wu G, Cao YL. Lu CM. Correction of the lack of commutability between plasmid DNA and genomic DNA for quantification of genetically modified organisms using pBSTopas as a model. Anal Bioanal Chem. 2014;406:6385–97.CrossRefGoogle Scholar
  50. 50.
    Cao YL, Wu G, Wu YH, Nie SJ, Zhang L. Lu CH. Characterization of the transgenic rice event TT51-1 and construction of a reference plasmid. J Agric Food Chem. 2011;59:8550–9.CrossRefGoogle Scholar
  51. 51.
    Takabatake R, Akiyama H, Sakata K, Onishi M, Koiwa T, Futo S, et al. Development and evaluation of event-specific quantitative PCR method for genetically modified soybean A2704–12. Shokuhin Eiseigaku Zasshi. 2011;52(2):100–7.CrossRefGoogle Scholar
  52. 52.
    Lievens A, Bellocchi G, Bernardi DD, Moens W, Savini C, Mazzara M, et al. Use of pJANUSTM-02-001 as a calibrator plasmid for Roundup Ready soybean event GTS-40-3-2 detection: an interlaboratory trial assessment. Anal Bioanal Chem. 2010;396:2165–73.CrossRefGoogle Scholar
  53. 53.
    Zhang H, Yang L, Guo J, Li X, Jiang L, Zhang D. Development of one novel multiple-target plasmid for duplex quantitative PCR analysis of roundup ready soybean. J Agric Food Chem. 2008;56:5514–20.CrossRefGoogle Scholar
  54. 54.
    Li Z, Li X, Wang C, Song G, Pi L, Zheng L, et al. One Novel multiple-target plasmid reference molecule targeting eight genetically modified canola events for genetically modified canola detection. J Agric Food Chem. 2017;65(38):8489–500.CrossRefGoogle Scholar
  55. 55.
    Pi L, Li X, Cao Y, Wang C, Pan L, Yang L. Development and application of a multi-targeting reference plasmid as calibrator for analysis of five genetically modified soybean events. Anal Bioanal Chem. 2015;407(10):2877–86.CrossRefGoogle Scholar
  56. 56.
    Wu Y, Li J, Wang Y, Li X, Li Y, Zhu L, et al. Development and application of a general plasmid reference material for GMO screening. Plasmid. 2016:87, 28–8, 36.Google Scholar
  57. 57.
    Kim J-H, Park S-B, Roh H-J, Shin M-K, Moon G-I, Hong J-H, et al. Event-specific qualitative and quantitative detection of five genetically modified rice events using a single standard reference molecule. Food Chem. 2017;226:187–92.CrossRefGoogle Scholar
  58. 58.
    Wang X, Teng D, Yang Y, Tian F, Guan Q, Wang J. Construction of a reference plasmid molecule containing eight targets for the detection of genetically modified crops. Appl Microbiol Biotechnol. 2011;90(2):721–31.CrossRefGoogle Scholar
  59. 59.
    Yang L, Guo J, Pan A, Zhang H, Zhang K, Wang Z, et al. Event-specific quantitative detection of nine genetically modified maizes using one novel standard reference molecule. J Agric Food Chem. 2007;55(1):15–24.CrossRefGoogle Scholar
  60. 60.
    Kuribara H, Shindo Y, Matsuoka T, Takubo K, Futo S, Aoki N, Hirao T, Akiyama H, Goda Y, Toyoda M, Hino A. Novel reference molecules for quantitation of genetically modified maize and soybean. J AOAC Int 2002; 85(5):1077–89.Google Scholar
  61. 61.
    Pardigol A, Guillet S. Popping B. A simple procedure for quantification of genetically modified organisms using hybrid amplicon standards. Eur Food Res Technol. 2003;216:412–20.CrossRefGoogle Scholar
  62. 62.
    Block A, Schwarz G. Validation of different genomic and cloned DNA calibration standards for construct-specific quantification of LibertyLink in rapeseed by real-time PCR. Eur Food Res Technol. 2003;216:421–7.CrossRefGoogle Scholar
  63. 63.
    Taverniers I. Windels, P. Vaitilingom M, Milcamps A, Van Bockstaele E, Van den Eede G, De Loose M. Event-specific plasmid standards and real-time PCR methods for transgenic Bt11, Bt176, and GA21 maize and transgenic GT73 canola. J Agric Food Chem 2005; 53(8):3041–52.Google Scholar
  64. 64.
    Tsukahara K, Takabatake R, Masubuchi T, Futo S, Minegishi Y, Noguchi A, et al. Development and evaluation of event-specific quantitative PCR method for genetically modified Soybean MON87701. Shokuhin Eiseigaku Zasshi. 2016;57(6):187–92.CrossRefGoogle Scholar
  65. 65.
    Takabatake R, Masubuchi T, Futo S, Minegishi Y, Noguchi A, Kondo K, et al. Selection of suitable DNA extraction methods for genetically modified Maize 3272, and development and evaluation of an event-specific quantitative PCR method for 3272. Shokuhin Eiseigaku Zasshi. 2016;57(1):1–6.CrossRefGoogle Scholar
  66. 66.
    International Organization for Standardization. General requirements for the competence of reference material producers. ISO Guide. 2000;34:2000.Google Scholar
  67. 67.
    Yang Y, Li L, Yang H, Li X, Zhang X, Xu J, et al. Development of certified matrix-based reference material as a calibrator for genetically modified Rice G6H1 analysis. J Agric Food Chem. 2018;66(14):3708–15.CrossRefGoogle Scholar
  68. 68.
    International Organization for Standardization. Guide to the Expression of Uncertainty in Measurement, ISO/IEC Guide 98–3:2008, Geneva, Switzerland.Google Scholar
  69. 69.
    Certification report: The certification of reference materials of dry-mixed maize powder with different mass fractions of BT-176 maize. Certified reference materials ERM-BF411a, -BF411b,-BF411c, -BF411d, -BF411e, -BF411f. EUR Report 20988, ISBN 92-894-6872-6. Luxembourg: Publications Office of the European Union, © European Union, 2004.Google Scholar
  70. 70.
    Certification report: The certification of reference materials of maize seed powder with different mass fractions of the maize event 3272 Certified Reference Materials ERM®-BF420 (ERM®-BF420a, ERM®-BF420b, ERM®-BF420c). EUR Report 22698 EN, ISSN 1018-5593, ISBN 978-92-79-05219-4. Luxembourg: Publications Office of the European Union, © European Union, 2007.Google Scholar
  71. 71.
    Certification report: The certification of the copy number concentration of solutions of plasmid DNA containing a BCR-ABL b3a2 transcript fragment, Certified Reference Materials: ERM®-AD623a, ERM®-AD623b, ERM®-AD623c, ERM®-AD623d, ERM®-AD623e, ERM®-AD623f. EC certification report EUR 25248 EN, ISBN 978-92-79-23343-2,ISSN 1831-9424. https://doi.org/10.2787/59675. Luxembourg: Publications Office of the European Union. © European Union, 2012.
  72. 72.
    Papazova N, Malef A, Degrieck I, Van Bockstaele E. De Loose M. DNA extractability from the maize embryo and endosperm-relevance to GMO assessment in seed samples. Seed Sci Technol. 2005;33:533–42.CrossRefGoogle Scholar
  73. 73.
    Zhang D, Corlet A, Fouilloux S. Impact of genetic structures on haploid genome-based quantification of genetically modified DNA: theoretical considerations, experimental data in MON 810 maize kernels (Zea mays L.) and some practical applications. Transgenic Res. 2008;17:393–402.CrossRefGoogle Scholar
  74. 74.
    Trifa Y, Zhang D. DNA content in embryo and endosperm of maize kernel (Zea mays L.): impact on GMO quantification. J Agric Food Chem. 2004;52:1044–8.CrossRefGoogle Scholar
  75. 75.
    Schweizer L, Yerk-Davis GL, Phillips RL, Srienc F, Jones RJ. Dynamics of maize endosperm development and DNA endoreduplication. Proc Natl Acad Sci U S A. 1995;92:7070–4.CrossRefGoogle Scholar
  76. 76.
    Certification report: Certification of a MON 810 maize reference material for its DNA copy number ratio, ERM®-BF413d. EC certification report EUR 23028, ISBN 978-92-79-07463-9. Luxembourg: Publications Office of the European Union, © European Union, 2007.Google Scholar
  77. 77.
    Certification report: Certification of a soya 356043 reference material for its DNA copy number ratio. Certified reference material ERM®-BF425c. ISBN 978-92-79-19070-4. EUR 24695 EN. Luxembourg: Publications Office of the European Union, © European Union, 2011.Google Scholar
  78. 78.
    Certification report: Certification of a maize NK603 reference material for its DNA copy number ratio. Certified reference material ERM®-BF415e. ISBN 978-92-79-19074-2. EUR 24699 EN. Luxembourg: Publications Office of the European Union, © European Union, 2011.Google Scholar
  79. 79.
    Certification report: Certification of a maize 98140 reference material for its DNA copy number ratio. Certified reference material ERM®-BF427c. ISBN 978-92-79-19279-1. EUR 24718 EN. Luxembourg: Publications Office of the European Union, © European Union, 2011.Google Scholar
  80. 80.
    Certification report: Certification of reference materials of maize seed powder containing genetically modified MON 810 Maize, Certified reference materials ERM®-BF413k (ERM®-BF413ak, ERM®-BF413ck, ERM®-BF413ek, ERM®-BF413gk). EUR 23986 EN, ISBN 978-92-79-13420-3, ISSN 1018-5593.  https://doi.org/10.2787/14844. Luxembourg: Office for Official Publications of the European Communities © European Communities, 2009.
  81. 81.
    Certificate of Analysis AOCS 1208-A, MIR162 maize. https://www.aocs.org/store/shop-aocs/shop-aocs?productId=125101624
  82. 82.
    O'Connor G, Dawson C, Woolford A, Webb KS, Catterick T. Quantitation of oligonucleotides by phosphodiesterase digestion followed by isotope dilution mass spectrometry: proof of concept. Anal Chem. 2002;74(15):3670–6.CrossRefGoogle Scholar
  83. 83.
    Sanders R, Huggett JF, Bushell CA, Cowen S, Scott DJ, Foy CA. Evaluation of digital PCR for absolute DNA quantification. Anal Chem. 2011;83(17):6474–84.CrossRefGoogle Scholar
  84. 84.
    Dobnik D, Spilsberg B, Bogožalec Košir A, Holst-Jensen A, Žel J. Multiplex quantification of 12 European Union authorized genetically modified maize lines with droplet digital polymerase chain reaction. Anal Chem. 2015;87(16):8218–26.CrossRefGoogle Scholar
  85. 85.
    Gerdes L, Iwobi A, Busch U, Pecoraro S. Optimization of digital droplet polymerase chain reaction for quantification of genetically modified organisms. Biomol Detect Quantif. 2016;7:9–20.CrossRefGoogle Scholar
  86. 86.
    Jiang Y, Yang H, Quan S, Liu Y, Shen P, Yang L. Development of certified matrix-based reference material of genetically modified rice event TT51-1 for real-time PCR quantification. Anal Bioanal Chem. 2015;407(22):6731–9.CrossRefGoogle Scholar
  87. 87.
    Huggett JF, Foy CA, Benes V, Emslie K, Garson JA, Haynes R, et al. The digital MIQE guidelines: minimum information for publication of quantitative digital PCR experiments. Clin Chem. 2013;59(6):892–902.CrossRefGoogle Scholar
  88. 88.
    Yoo HB, Park SR, Dong L, Wang J, Sui Z, Pavšič J, et al. International comparison of enumeration-based quantification of DNA copy-concentration using flow cytometric counting and digital polymerase chain reaction. Anal Chem. 2016;88(24):12169–76.CrossRefGoogle Scholar
  89. 89.
    Kline MC, Romsos EL, Duewer DL. Evaluating digital PCR for the quantification of human genomic DNA: accessible amplifiable targets. Anal Chem. 2016;88(4):2132–9.CrossRefGoogle Scholar
  90. 90.
    Košir AB, Divieto C, Pavšič J, Pavarelli S, Dobnik D, Dreo T, Bellotti R, Sassi MP, Žel J. Droplet volume variability as a critical factor for accuracy of absolute quantification using droplet digital PCR. Anal Bioanal Chem 2017; 409(28):6689–6697.Google Scholar
  91. 91.
    Corbisier P, Pinheiro L, Mazoua S, Kortekaas AM, Chung PY, Gerganova T, Roebben G, Emons H, Emslie K. DNA copy number concentration measured by digital and droplet digital quantitative PCR using certified reference materials. Anal Bioanal Chem 2015; 407(7): 1831–1840.Google Scholar
  92. 92.
    Duewer DL, Kline MC, Romsos EL, Toman B. Evaluating droplet digital PCR for the quantification of human genomic DNA: converting copies per nanoliter to nanograms nuclear DNA per microliter. Anal Bioanal Chem. 2018;410(12):2879–87.CrossRefGoogle Scholar
  93. 93.
    Kline MC, Duewer DL. Evaluating droplet digital polymerase chain reaction for the quantification of human genomic DNA: lifting the traceability fog. Anal Chem. 2017;89(8):4648–54 64.S.CrossRefGoogle Scholar
  94. 94.
    Bhat S, Emslie KR. Digital polymerase chain reaction for characterisation of DNA reference materials. Biomol Detect Quantif 2016; 10:47–49.Google Scholar
  95. 95.
    Haynes RJ, Kline MC, Toman B, Scott C, Wallace P, Butler JM, et al. Standard reference material 2366 for measurement of human cytomegalovirus DNA. J Mol Diagn. 2013;15(2):177–85.CrossRefGoogle Scholar
  96. 96.
    European Commision, JRC. Information related to the new series of ERM-BF410p Certified Reference Materials. https://crm.jrc.ec.europa.eu/p/q/ERM-BF410/ERM-BF410cp-GTS-40-3-2-SOYA-BEAN-level-1-nominal-0-1-GMO/ERM-BF410cp
  97. 97.
    International Organization for Standardization. Reference material – general and statistical principles for certification. 2006; ISO Guide 35:2006.Google Scholar
  98. 98.
    ISAAA. Global Status of Commercialized Biotech/GM Crops: 2017. ISAAA brief No. 53, ISAAA: Ithaca, NY.Google Scholar
  99. 99.
    Demeke T, Perry DJ, Scowcroft WR. Adventitious presence of GMOs: scientific overview for Canadian grains. Can J Plant Sci. 2006;86:1–23.CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Key Laboratory of Oil Crop Biology of the Ministry of Agriculture, Oil Crops Research InstituteChinese Academy of Agricultural SciencesWuhanChina
  2. 2.Development Center of Science and TechnologyMinistry of Agriculture of People’s Republic of ChinaBeijingChina

Personalised recommendations