other 25 years to develop another organism to the level of un- 
derstanding now attained with E. coli is correct, I recognize 
that it will take time, and it is certainly not in the public 
interest to drive recombinant DNA research underground with such 
a ban . 
Perhaps a time limit such as that suggested by the Boston Group 
is advisable, although it would certainly have to be negotiable- 
target dates should certainly be possible. It is important 
to avoid slipping into a habit of thinking only in terms of E. 
coli , and becoming complacent about alternatives. Unfortunately, 
the fact that the guidelines are written entirely in terms of 
E. coll encourages assumptions of • this nature. 
The use of "safe" vector-host systems (EK2 and 3) does not en- 
tail the quantum leap in difficulty and expense of experiments 
that results from the increase of physical containment. The in- 
convenience resulting from restricting experimentation to these 
organisms is simply that genetic diversity of these systems is 
limited, and some experiments could not be performed within them. 
I suggest that all experimentation should be routinely restrict- 
ed to the safest available host-vector systems - EK2 or 3 level 
as soon as available (EK3 systems are simply the same EK2 sys- 
tems subjected to further testing, and thus are no different 
to work with). The use of any but the safest available system 
should be permitted only by a petition to the Program Advisory 
Committee delineating why the experiments cannot be modified 
to permit them to be performed in safer systems, and why they 
should not be postponed until a suitable EK3 or 2 level sys- 
tem can be developed. Such a procedure s2>uld provide a strong 
incentive for remaining within the saf e st possible systems, and 
for the development of a diverse array of safe host-vector sys- 
tems . 
I also would strongly discourage the use of any virus known 
to infect humans, such as SV40, as the effects of such infect- 
ions may not be known for a generation. I would urge a procedure 
such as that suggested above, in which expe rin&M&/SV40 or any 
virus infecting humans would be allowed only if it were demon- 
strated that there was no other way to obtain the information 
and that experiments should not be postponed, and then permitted 
only under the most stringent conditions. 
Implementation - The method of implementation of these guide- 
lines is an important consideration in judging how effectively 
the scientific community has dealt with this crisis, for if 
they are loosely or irregularly applied, the past two and a 
half years of soul-searching and altruistic behavior will have 
been in vain. 
It is not clear to me tha.t peer group review of hazards and 
safe guards adds very much to the initial assessment of the in- 
[464] 
