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1 proposed revisions of the guidelines are justifiable on 
2 the basis of recent experience with recombinant DNA and 
3 on the basis of a rational reconsideration of potential 
4 hazards of microorganisms containing recombinant DNA. 
5 I also believe that the revisions will allow a more 
6 natural and creative development of research in those 
7 many areas of biology and medicine to which recombinant 
8 DNA methods are applicable, resulting in advances that 
g would not occur under the present guidelines. 
10 For example, there are many experiments which 
now simply are not done because of the restrictions of the 
12 guidelines, and in particular I want to emphasize there 
13 are many scientists who cannot participate in this 
14 research because they are institutions that don't have 
15 the appropriate facilities. 
I need not recite the experience with recombinant 
17 DNA over the past four years. On the one hand, the great 
18 promise of the methodology is clearly being realized. And 
19 on the other, no single instance of harmful effect has been 
2Q reported. During these years also, additional instances 
21 of natural, interspecies recombination of DNA between microbes 
22 or between viruses and cells have been described that make it 
23 appear that such genetic interchange is widespread in nature. 
24 Therefore, there is now less concern both about the imminent 
25 "escape" of an artificial pathogen, and about the novelty of 
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