SEPTEMBER 6-7 - MINUTES OF MEETING 
30 
rioted that this proposal is quite broad; he said Dr. Chilton is asking for 
permission to institute a new HV system. He noted that there is no 
restriction on the DMA which is to be transferred and he questioned 
whether such blanket approval is appropriate. Dr. Novick recommended 
that the RAC, in view of the restrictiveness of the current containment 
procedures as applied to Agrobacterium tumefaciens , approve the following 
lessening of restrictions: 
"A. tumefaciens may be used as a host for 
cloning into the Ti plasmid or in experiments 
which amount to the equivalent of that at a 
level of containment one step higher than would 
ordinarily be required for the DNA segment 
involved. The DNA segment to be cloned 
must be well characterized. Introduction of 
these cloned segments into plant tissue would 
require the same level of containment as the 
clones" . 
Dr. Gottesman said that Dr. Chilton was proposing equivalency plus one 
level of containment. C*r . Gottesman questioned whether this type of 
approach is appropriate. She did not feel the levels set for El. coli 
should be transferred to any other organism. For instance, cloning of 
DNA of some plant pathogens into El. coli is at lower containment than 
cloning of primate DNA. She said it makes no sense to carry this over 
to A. tumefaciens . Dc. Brill asked what types of problems could arise 
from acceptance of this proposal. Dr. Novick responded that Agrobacterium 
is an economic hazard; it causes losses in agriculture. Dr. Broad bent 
replied that losses occur primarily in nursery stocks. Ct. Novick 
questioned whether you might be extending the host range of A. tumefaciens . 
Dr. Brill replied that it has a tremendous host range already. Dr. Novick 
said that a wild-type plant path ■'gen with a conjugation proficent plasmid 
is not an appropriate organism to use as a HV1 host according to the 
Guidelines as presently written. 
Dr. Young said kncv/ledge of the Agrobacterium system is relatively unsophis- 
ticated as compared to other HV systems. Dr. Gottesman said that information 
on the types of exchanges in which this soil organism might participate 
is lacking. In addition, she noted that the mechanisms by which its 
pathogenicity is limited is unknown. Could tranfer from another pathogen 
give it an increased virulence? Dr. Brill said much exchange already 
occurs in the soil. Dr. Zaitlin moved to accept the proposal as in the 
Federal Register . The RAC accepted this by a vote of nine for, six 
against, with two abstentions. 
[ 179 ] 
