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In general, it is always prudent to analyze data statistically when such analysis is possible. When unpublished information or an opinion has been supplied by a scientific expert, a letter communicating the information should be included in the petition. If the unpublished information provided is data resulting from scientific research then these data can be provided as a personal communication either in a letter from the researcher or in the text of the petition. In either case the materials and methods, data analysis, and discussion of the data analysis should be provided in detail. Unsupported assertions about the results of the experiment are not acceptable.

Applicants must report any differences noted between transgenic and nontransgenic plants that are not directly attributed to the expected phenotype. Differences observed could include changes in leaf morphology, pollen viability, seed germination rates, changes in overwintering capabilities, insect susceptibilities, diseases resistance, yield, agronomic performance etc. Applicants must also note the types of characteristics that were compared between transgenic and nontransgenic plants and found to be unchanged.

The applicant should describe whether data submitted are from inbred or hybrid plants; if hybrid plants, state which generation.

State whether data with respect to plant performance were generated in a greenhouse or field environment. If from the field, indicate how many sites, states and number of years the data represents.

Seed germination, seed dormancy, seed production, growth rate, and other data relating to the plant’s performance will be required when the nature of the gene and the biology of the plant (including sexually- compatible relatives) warrant such data. This type of data will usually not be required for plants that have some of the following attributes: are highly domesticated (e.g., corn), are exclusively self-pollinating (e.g., soybean), are male sterile, and have high seed germination rates (>90%), and whose phenotypes are unlikely to affect performance with respect to weediness or fitness (e.g., delayed ripening or oil seed modification). Phenotypes that might require performance data (depending on the plant) include but are not limited to the following: cold tolerance, salt tolerance and tolerance or resistance to other biotic or abiotic stresses.

SAMPLE PETITIONHerbicide-Tolerant Plants

  • V.

    Genetic Analysis and Agronomic Performance

  • A.

    Southern Gel Analysis

The identity of the genetic material that was integrated into the genome of the transgenic plant was probed by Southern hybridization. In order to determine the number of insertion events, the DNA from the transgenic regulated plant and the parental Stoneville 825 recipient lines were digested with the restriction enzyme Nde1, which does not cleave within the pVST1 DNA. The hybridizations done with three probes indicated that the foreign DNA integrated at one site to yield the transgenic plant. This is supported by the presence of one hybridizing fragment of 20 kb that is present in the transgenic DNA but is absent from the parent.

The following restriction fragments were labeled and hybridized to the Southern blots:

  • 1.

    a 300 bp EcoR 1 fragment of the aroA gene

  • 2.

    a 400 bp BamH 1 fragment of the nptII gene

  • 3.

    a 950 bp Pst 1 fragment with the amp and lac genes that are not expressed in plants and should not be integrated into the plant

Hybridization analysis of genomic DNA was performed following the method of Firoozabady et al. (1987). The results are shown in figure 2 for the aroA, nptII and Amp marker genes. Both aroA and nptII probes hybridize to the 20Kb fragment in lane 1. The data support the Mendelian results (shown below) that only one expressed copy of the aroA gene is present in the engineered cultivar and that a single copy of the npt II marker gene is present. No hybridization with the ampicillin or lac probe was detected.

Southern blot analysis supports the conclusion that the amp+lac sequences which lie outside the Ti plasmid left and right borders, were not integrated in to the genome of Banjaran, while the sequences inside the Ti left and right borders were.


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