Testimony of Mary-Dell Chilton 
Introduction Section 
I favor the idea of excluding certain recombinant DNA 
experiments from regulation by the Guidelines. By excluding 
from consideration a large number of experiments which are 
innocuous, we focus attention on the more critical issues, 
where it properly belongs. However two questions are not 
clearly answered by the statements in the Introduction 
defining what is meant by the term "novel recombinant DNA" . 
1. Two apparently alternative criteria are stated for 
judging the novelty of a recombinant DNA molecule. Must it 
be non-novel by both criteria in order to be eligible for 
exclusion from the Guidelines, or is either criterion sufficient? 
A case in point occurs in the research in which I am involved: 
cloning of the Agrobacterium Ti plasmids in E. coli . Experiments 
in the laboratory of Dr. Jeff Schell, State University, Ghent, 
Belgium (see appended signed statement) have shown that the 
Ti plasmids can be transmitted to E. coli from Agrobacterium 
by conjugation, and that the Ti plasmid can replicate in E. 
coli . although it does so only poorly. Thus cloning Ti plasmid 
DMA in E. coli involves a "combination of DHAs ... derived from 
genomes known to replicate within the organism used to propagate 
the recombinant DNA," and such recombinant DNA could be considered 
non-novel. However such recombinant DNA is novel according to 
the other stated criterion, for it does "consist of segments 
[Appendix A — 150] 
