MINUTES OF MEETING - March 6-7 
16 
He did not at that time, however, accept 
"Organisms which show evidence of a plausible mechanism for 
exchange (e.g., R' formation or evidence of mobilization of 
chromosomal genes by an Inc P-1 plasmid)" or 
"Organisms which can receive or donate broad host range plasmids." 
She questioned whether Dr. Kado's argument of relatedness by 20 percent 
sequence homology was sufficient to warrant the inclusion of the genus 
Erwinia in Appendix A. 
Dr. Falkcw recounted his participation in the development of Appendix A. 
He said that he believes that chromosomal sequence homology of 20 percent 
or greater indicates sufficient relatedness to warrant inclusion of organ- 
isms on sublists in Appendix A. He said that Erwinia shares a sufficient 
core of sequence homology with the other Enterobacteriaceae to warrant 
inclusion in Appendix A, Sublist A. Dr. Young agreed. 
Dr. Brill restated his motion to change the listing on Sublist A, Appen- 
dix A from Erwinia amylovora to the genus Erwinia. The RAC accepted this 
recommendation by a vote of fourteen in favor, none opposed, and three 
abstentions. 
XIII. PROPOSAL TO AMEND PORTIONS OF SECTION III-A-2-a 
Dr. Nightingale said that she and Dr. Brill had been asked to examine the 
applicability of the terminology "HVICV" to host-vector systems other 
than Escherichia coli K-12. She said a recommendation (tab 843/8) to 
change the biological containment requirement frcm HVICV to HV2 within 
the subsections of Section III-A-2-a was advanced since it was felt that 
the CV terminology could not be generalized to host-vector systems other 
than Escherichia coli K-12. She said that in the EK system, CV contain- 
ment depends on the plasmid, and the properties of these plasmids can 
not be generalized to other host- vector systems. She added that in pro- 
posing this change she hoped to encourage discussion of the issue. She 
moved that the proposal be approved as it appeared in the Federal Register . 
Dr. Gottesman supported the contention that EK1CV could not be generalized 
to other host-vector systems. She said that historically the EK1CV nomen- 
clature stood for an EK1 host and a vector certified for use in an EK2 
system, and was a position between EK1 and EK2 containment. Dr. Baltimore 
said the CV nomenclature is meaningless in the yeast system and should 
be amended. He said HV2 containment is too stringent and suggested that 
HVl be substituted for HVICV. Dr. Gottesman said a proposal substituting 
HVl containment for HVICV would have to be republished in the Federal 
Register as a preposed major action. 
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