15 
naturaL recombination events. They also took into account new knowledge 
about E. col i K-12 and EK2 systems that we will hear about later today. 
They introduced the concept of novel , and attempted to devise a way to elim- 
minate extension of the regulations to certain unnecessary species where 
where this recombination was clearly evident in nature. 
We note that both of the pieces of legislation still not passed in 
Congress also included restriction of the definition. 
The proposed revisions then include the introduction of this concept 
of a novel event with definition. Note that the Committee still leaves 
the burden on the investigator, however, to prove the novelty, or to prove 
the lack of novelty, of the experiments that he might propose to do. Exemp- 
tions from the Guidelines would be derived primarily by a list, which the 
revisions say would be prepared by the Director with the advice of the Recom 
binant Advisory Committee, to which I would add, certainly, that they should 
be published and revised periodically. But it does mean that a good deal of 
work will have to be done very early to prepare a list of such exemptions, 
and for that a subcommittee has already been put in place by the Recombinant 
Advisory Committee if this portion of the revisions is accepted. 
I just want to say before giving the Committee an opportunity to ex- 
change with Drs. Singer and Littlefield, whether Dr. Spizizen — John Spizizen 
are you here? 
DR. SPIZIZEN: Yes. 
DR. FREDRICKSON: Would you tell us whether you have done some thinking 
as to how a subcommittee would proceed to work on the task of preparing such 
a list? 
DR. SPIZIZEN: We have just begun our deliberations, and have not 
really come to the point where we can really define a list. Our general 
feeling is that such a list would be only very tentative, in the sense that 
we don't have enough data in the literature. It would probably be a ques- 
tion of providing some well-known situations and then perhaps to issue: 
statements or guidelines for future requests to be inserted on this li.st. I 
think that such a list is, academically, at the moment not at all possible. 
We will prepare a partial list, and hopefully this will be added to in the 
future . 
DR. FREDRICKSON: What you mean is that a complete and all-inclusive 
list is quite academic? 
DR. SPIZIZEN: That is right. 
DR. FREDRICKSON: But it would be your intent, then, to place the bur- 
den of proof on the investigator, so to speak, and that the RAC would deal 
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