The Advisory Committee for Biotechnology and 21st Century

Agriculture (AC21)

Accuracy for Quantitative Testing of Biotechnology Derived Grains

Steven N. Tanner, Director, Technical Services Division

December 5, 2003

▪ Facilitate U.S. grain markets

▪ When testing is needed, ensure reliability and credibility of testing for transgenic grains and oil seeds

GIPSA and Biotechnology

USDA/GIPSA Proficiency Program

▪ Improve the reliability of testing for biotechnology events

▪ 86 organizations now participating

▪ Corn events: T25, CBH351, MON810, GA21, E176, Bt11 and NK603; TC1507 and MON863 to be added in FY 2004

▪ Soybeans: Glyphosate tolerance

USDA/GIPSA Proficiency ProgramGlobal Program

Area Feb 2002 Nov. 2003Africa 0 1Australia 0 1Asia 1 8Europe 5 39 South America 1 10 North America 15 27

Total Participants 22 86

USDA/GIPSA Proficiency Program

▪ Voluntary participation

▪ Participant anonymity

▪ Offered quarterly

▪ Qualitative and quantitative

▪ Results on GIPSA’s biotechnology web page

General Observations▪ Participants use protein and DNA-based tests▪ Qualitative results correct > 90 % of the time

Quantitative Sample Results:▪ Average results were lower than target level ▪ Coefficients of variation (CV’s) ranged from

~30 to >100 %▪ False negatives/positives were < 10 % except at lowest levels (i.e., 0.1 %)

USDA/GIPSA Proficiency Program Observations

Relative Measurement VariabilityAnalyte STD* CV (%)*1 ppb 0.45 45

1 ppm 0.16 16

1 % 0.04 4

DNA-Based Testing** STD Range CV Range0.1 % 0.06-0.50 80-190

1.5 % 0.50-1.15 42-93

5.0 % 1.12-4.20 36-90

*Horwitz predicted values**Actual values reported in Proficiency Program (% by wt)

▪ Methods - Patent Protection/Intellectual Property - Limited official protein-based methods - No globally recognized methods for conventional or real time PCR

▪ Reference Materials - Limited availability - No general agreement (seed, grain,

plasmids, etc.)

Testing Challenges

International Collaboration of Quantitative Methods

Real Time PCR TechniquesDNA Isolation ProceduresDNA Quantitation Technologies

▪ International Reference Materials: GIPSA and NIST Workshop on June 27, 2003

Addressing the Challenges

▪ Protein and DNA reference materials

▪ Matrix reference materials

▪ Global convention for expressing results

GIPSA/NIST Workshop Recommendations

▪ USDA GIPSA▪ NIST▪ Life Science Organizations▪ Institute for Reference Materials and Measurements (IRMM/Europe)▪ National Research Council (NRC/Canada)▪ National Food Research Institute (NFRI/Japan)▪ International Organizations (Codex, ISO, CEN, AOAC-I, AACC, and AOCS)

Key Organizational Cooperation

USDA Biotechnology Webpage

www.usda.gov/gipsa/biotech/biotech.htm