ISTAs Position, Experience and Activities in the Field of Biotech Trait Detection

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ISTAs Position, Experience and Activities in the
Field of Biotech Trait Detection

• ISTA GMO TF
• B.R. Kahlert
• S. Grégoire, C. Haldemann, K. Remund, J.L.
  Laffont
• and many others

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Outline

• What is ISTA?
• ISTA and of GM Seed Testing
• Accreditation
• Proficiency Tests
• Performance Data Evaluation
• Audit
• ISTA can help, ISTA helps to share
• Workshops, Seedcalc, Website

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Objectives of the International Seed Testing
Association

• The primary purpose of the Association is to
  develop, adopt and publish standard procedures
  for sampling and testing seeds, and to promote
  uniform application of these procedures for
  evaluation of seeds moving in international
  trade.
• The secondary purposes of the Association are
  actively to promote research in all areas of seed
  science and technology, to participate in
  conferences and training courses aimed at
  furthering these objectives, and to establish and
  maintain liaison with other organisations having
  common or related interests in seed.

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ISTA Laboratories Worldwide

• More than
• 160 laboratories,
• 200 personal members,
• originating from 70 countries supporting the
  association (Government mandates)  

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ISTAs major Products Services

• International Rules for Testing Seed
• Sampling, Purity, Other Seeds, Germination,
  Tetrazolium, Seed Health, Species and Variety
  Testing, Moisture, Coated Seed, Vigour, X-ray
• seeds of agricultural vegetable flowers,
  spice, herb medicinal tree shrubs
• Proficiency Test Programme
• Laboratory Accreditation Programme
• International Seed Lot Certificates

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ISTAs Vision Strategy inTesting of GM Seeds

• ISTA Seed Testing Laboratories are competence
  centres for detection, identification and
  quantification of GM seeds
• ISTA focuses its activity on developing and
  maintaining a system that ensures reliability and
  accuracy of results all over the world, when
  testing for GM seeds Performance Based Approach
• defined in the Position Paper
• ISTAs Strategy Regarding Methods for the
  Detection, Identification and Quantification of
  Genetically Modified Seeds in Conventional Seed
  Lots
• adopted by the Executive Committee Nov. 2001

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ISTAs Actions in Testing of Seed with Specified
Trait(s)

• Chapter in ISTA Rules for testing of seeds with
  specified trait(s)
• Implementation of Laboratory Accreditation under
  Performance Based Approach
• Organising proficiency tests on detection and
  quantification of GM seeds in conventional seed
• Establishing a system for Performance Data
  Evaluation for the Presence of Seed with
  Specified Trait(s) in Seed Lots and Specified
  Trait Purity
• Provide technical help for the laboratories
  (training courses, workshops, Seedcalc7, ...)

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1. Chapter in the ISTA Rules

• Rules for the testing of seeds with specified
  traits including the detection, identification
  and quantification of GM seeds came into force in
  February 1st, 2006
• The Rules do not contain specific methods, but
  define the general principles in testing and
  reporting results of such tests
• Laboratories having methods for GM seed testing
  in their scope of accreditation can report the
  test results on the International Seed Analysis
  Certificate

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2. Conditions for ISTA Accreditation under the
Performance Based Approach

• Laboratory ...
• Has established method(s)
• Defines scope of accreditation
• Participates successfully in the ISTA Proficiency
  Test Programme
• Submits performance data
• Has an audit

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3. Organisation of Proficiency Tests

• AIMS
• to evaluate the performance of participating
  laboratories
• to collect data to be used to set performance
  standards
• To increase experience for ISTA and participating
  laboratories
• Satisfactory performance in proficiency tests is
  a prerequisite for attaining or maintaining the
  status as an accredited laboratory
• Laboratories can participate to ISTA proficiency
  tests, even if they do not seek accreditation

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Design of the 6th Proficiency Test

• crop Brassica napus L.
• of samples per lab 10
• of negative samples 3
• of positive samples 7 0.3 2 0.6
  3 1.2 2
• event GT73
• sample size 3300 seeds
• Qualitative and Quantitative tests
• the laboratory chooses the method

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Qualitative Test The detection of GM seeds in
samples

• 49 labs classified each of the 10 samples as
  either positive or negative.
• 4 laboratories reported false results. These
  are 8 of the laboratories.
• Sample classified as false...

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Sub-sampling Quantification

• Laboratorys estimated results and its mean

Spiking level 0.3
Spiking level 0.6
Spiking level 1.2
Estimate of GM seeds

• 12 laboratories reported the test plan...
• the size of sub-samples (in number of seeds)
• the number of sub-samples tested
• the number of positive sub-samples
• ? used to compute the result

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Quantitative Test

• 23 laboratories reported the GM content of the
  positive test samples in of GM seed by number
  or by mass or in DNA copies

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Summary PT06

• PT06 - Qualitative Results
• The percentage of laboratories reporting correct
  results for all samples is higher as in the
  previous tests
• gt90 of labs made no missclassification,
• gt97 of samples are reported correctly
• PT06 - Quantitative Results
• The results show similar variation for the the
  spiking level (VC 50)
• Most laboratories overestimated the true level

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Design of the ISTA Proficiency Tests
110 laboratories from 42 countries
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PT01 PT06 Qualitative Tests
Percentage of laboratories reporting results
correctly or falsely Percentage of samples
reported correctly or falsely
PT01 maize, MON810 T25 1 PT02 maize
MON810 0.7 1.4 PT03 maize MON810
T25 0.2, 2 4 PT04 soybean GTS40
0.1, 0.5 1.0 PT05 soybean GTS40
A2704 0.2, 0.5, 1.0, 1.5 PT06
rapeseed GT70 0.3, 0.6 1.2

•  

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PT01 PT06 Quantitative Test

• (Overall) mean of the quantitative test results
  for each spiking level

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PT01 PT06 Quantitative Test

• Variation coefficient of the quantitative test
  results

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Summary PT01-PT06

• Qualitative Results
• Better results when
• only one transgenic event involved
• transgenic events are well known
• Better results for negative samples than for
  positive samples
• Quantitative Results
• Reported values close to the true value
• when spiking level between 0.2 and 1.5
• when transgenic event and reference material are
  well known

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How to evaluate the performance of laboratories
in ISTA Proficiency Tests?

• A No problem has been detected in this test
• B There are small problems, but no specific look
  or action is suggested to the participant
• C Problems, ISTA indicates there might be things
  to consider by the laboratory to explain or
  correct things
• BMP Below Minimum of Performance, ISTA indicates
  that the results were poor and the laboratory
  need to find explanations and to improve/correct

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In-round rating Presence/absence3 suggested
rating systems
Example with 10 samples in a Test

System3
System1
System2
2 mistakes 2/1020
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In-round Rating Principles for Quantification
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PT06 Rating

• Qualitative Test (49 labs) Quantitative and
  Sub-sampling Quantitative Tests (35 labs)

RS1 seed number RS2 mass of seed RS3 median
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PT01-PT06 In-round Rating

• of laboratories which reported an A, B, C or
  BMP
• Qualitative Results Quantitative Results

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PT01-PT06 Overall Rating

• Rating System for 6 PTs based on the in-round
  rating values
• Qualitative Results
• Quantitative Results

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4. Performance Data Evaluation

• for presence of seed with specified trait(s) in
  seed lots and specified trait purity
• Laboratory can choose an established and reliable
  method
• The Performance Based Approach is used instead
  of one ISTA validated method(not published in
  the ISTA Rules)
• Laboratory needs to demonstrate to ISTA
  accreditation team its ability to perform well
  with the method routinely used

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Scope of ISTA Accreditation

• Performance approved method to be included in
  labs scope of accreditation
• must be defined in terms of method used, the
  species tested, and the specified trait is to be
  determined

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Relevant PD Documents

• Evaluation of Performance Data for each
  combination species, test method and trait!
• For some combinations a PD has to be performed
  (on seeds, defined number of samples, defined
  spiking levels)
• For other combinations suitable alternative
  Performance Data may be used(any other data
  providing effidence that accuracy and
  repeatability criteria are met)

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Quantification of Trait(s)
Range 0.1 to 3
7 levels 4 samples
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Accuracy departure from true valueRepeatability
variability of results by level
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Example of use of the data sent by the laboratory
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Accuracy Departure from true value
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Repeatability variability of results by level
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Deviation and variability by level
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Grading performance
8.2
8.3
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Audit

• Auditors assess whether implementation aspects
  are appropriately addressed and whether practice
  complies with the documented procedures
• To that effect, training, equipment management,
  facilities, reporting and running the overall
  quality managements system will be assessed
• A complete practical demonstration of any
  performance approved method will not be required

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5. ISTA Workshops on GM Seed Testing
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http//www.seedtest.org
ISTA Web site