47 
1 a definitive decision on the proper containment levels, 
2 for in April 1973 I received a letter from William 
3 Gartland, Director, suggest incj that I submit a draft 
4 statement for consideration by ORDA on the containment 
5 levels of recombinant DNA research with ontonopathogenic 
6 bacteria that have EPA registration. On April 24 , 1973 , 
7 I submitted such a statement as required. 
8 Although the proposed revised guidelines will 
9 simplify the problem of this interpretation, there is 
10 still left a rather bothersome issue that is also found 
11 in other sections of the guidelines. Under Section III-B, 
12 "Experiments with Other Prokaryotic Host-Vectors," host-vector 
13 systems which have been approved as HV1 systems nay be 
14 used under P 2 containment conditions for shotgun experi- 
15 ments with phages, plasmids, and DNA from nonpathogenic 
16 prokaryotes which do not produce polypeptide toxins. 
17 Therein is the quandry. Both of the proposed organisms 
18 for recombinant DNA research are pathogenic, but only 
19 to target insects, and one of them, Bacillus thur ing iensis , 
20 produces a polypeptide toxin which is the basis of its 
21 pathogenicity. The toxin, however, is only specific for 
22 certain insects, and has been demonstrated ineffective 
23 against other life forms, including man. 
24 I would respectfully request that the NIH 
25 define more concisely the nature of the pathogenicity 
[139] 
