9 
Dr. Tolin proposed that Appendix L-II-C be modified to read as follows: 
"Appendix L-II-C. The vector cons ists of DNA: (i) from exempt 
host-vector systems (Appendix C); (ii) from plants of the same 
or closely related species; (iii) from nonpathogenic prokaryotes 
or nonpathogenic lower eukaryotic plants; (iv) from plant 
pathogens only if sequences resulting in production of disease 
symptoms have been deleted; or (v) chimeric vectors constructed 
from sequences defined in (i) to (iv) above. The DNA may be 
introduced by any suitable method. If sequences resulting in 
production of disease symptoms are retained for purposes of intro- 
ducing the DNA into the plant, greenhouse-grcwn plants must be 
stown to be free of such sequences before such plants, derivatives, 
or seed from them can be used in field tests." 
Dr. Tolin noted that, under the present language, the Plant Working Group 
might have to review proposals according to the strictest sense of the 
word "disease." This may preclude approval of proposals utilizing some 
plasmid and virus-derived nucleic acid vectors since in the strict sense 
their replication might be construed to be part of the disease process 
even if no symptoms develop in the plants. Dr. Tolin said certain of 
these sequences might be necessary to introduce the recombinant DNA into 
the plant. She said there are, moreover, methods for removing these 
sequences before the plants are tested in the field. The proposed modifi- 
cation specifies that data shewing elimination of these sequences would be 
evaluated by the Plant Working Group. 
Dr. Tolin said two transformation systems would be affected by modified 
Appendix L: the Ti plasmid of Agrobacterium and plant virus vectors such 
as cauliflower mosaic virus. Dr. Vidaver concurred with Dr. Tolin and 
said the Plant Working Group sees no danger per se in portions of the 
vector replicating as long as disease symptoms do not result. 
Dr. McGarrity asked how sequences introduced into the plant can be sub- 
sequently removed from plants. Dr. Vidaver said selection of cells could 
be made in tissue culture. These cells could then be manipulated in such 
a way that the plants regenerated from the cells can be assayed for the 
presence or absence of disease causing sequences. 
Dr. McGarrity moved acceptance of the proposal as it appeared in the Federal 
Register . Dr. Wens ink seconded the motion. 
By a vote of thirteen in favor, none opposed, and no abstentions, the RAC 
accepted the motion. 
VI. PRESENTATION BY MR. JEREMY RIFKIN 
Prior to the presentation by Mr. Jeremy Rifkin, Mr. Mitchell noted that the 
Department of Health and Human Services (HHS) and the National Institutes 
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