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B. Impact of Experiments Conducted Under the Guidelines 
1 . Possible Undesirable Impact 
a. Dispersion of potentially hazardous agents 
The hypothetical mechanisms by which insertion of foreign genes 
into cells or viruses might result in the formation of hazardous agents 
are described in Section IV-C of this EIS. The mechanisms are, in 
principle, applicable to persons, animals, and plants. There is, as 
stated before, no known instance in which a hazardous agent has been 
created by recombinant DNA technology. Current knowledge permits 
no more than speculation that such agents may be produced and an 
equally speculative assessment of the nature and extent of hazards 
associated with a particular recombinant DNA experiment. This is 
the underlying reason that the thrust of the Guidelines is to minimize 
contact of organisms containing recombinant DNA with other organisms 
or the environment. Therefore, the following analysis of possible un- 
desirable impacts due to dispersion of potentially hazardous agents 
emphasizes the likelihood of significant dispersion rather than the 
nature of the hazard itself. The analysis given does not apply in detail 
to all possible situations, but can serve as a model for analyzing 
different ones. 
In order that any potential hazard be realized, it is necessary that 
each of a number of sequential events occur. Each event in the sequence 
is possible only if the earlier events have occurred. The organism 
must- - 
(a) contain foreign genes, 
(b) escape from the experimental situation, 
(c) survive after escape, 
(d) become established in an environment permitting its growth 
and multiplication, 
(e) contact other living organisms in a significant manner, including 
contact by a sufficient number of organisms to ensure survival 
and growth and to cause infection. [Note that the environment 
in (d) may be a living organism itself. ] 
In those cases where the detrimental effect would result from the 
formation of a harmful protein, the organism containing the recombinant 
DNA would have to-- 
(f) contain a gene for a potentially harmful protein, 
(g) be able to express the foreign gene (that is, synthesize the 
corresponding protein) and 
