Dr. DeWitt Stetten, Jr. 
February 27, 1976 
Page 3 
implicating SV-40 as a causative agent of disease in man, not all the 
reports are negative, and follow-up data are as yet insufficient. 
Surveillance should be continued, because insufficient time may have 
elapsed since the administration of vaccine to be sure that no disease 
will result. The association of SV-40 virus with human tumors, such 
as metastatic melanomas and meningiomas, was referred to in the 
bibliography of Appendix B of the guidelines, but these papers were 
not referred to during the discussion at the February 9-10 meeting, 
leaving the misleading impression that no human disease has been 
associated with SV-40. 
3. It became clear during Dr. Brown’s presentation on February 10 
that the guidelines preclude "shotgun" experiments with cold-blooded 
vertebrates until an EK2 host becomes available. Prior to February 10, 
my impression was that EK2 was available and did not need further 
certification by the NIH advisory Committee. Cold-blooded animals 
(invertebrates) and lower eukaryotes are now all in one class requiring 
P2 physical containment and EK1 host vector, unless the eukaryote in 
this class is a known pathogen or carries such an agent. Thus, "shot- 
gun" experiments with any inveterbrate can be done now. The class- 
ification for "shotgun" experiments on the slide shown at the February 
meeting was simply "cold-blooded vertebrates" and the "lower eukaryotes". 
The "lower eukaryotes" include the arthropods. The phylum Arthropoda 
contains 85% of all known species of animals. In this phylum, the 
insect class is the largest and includes 800 species that have been 
described and probably missions that have yet to be described. The 
evolution of insects has at least three levels of specialization, and, 
according to C. P. Hickman ( Biology of Invertebrates . C. V. Mosby Co., 
1967, p. 449 ff), "Insects are the most extensive group of organisms 
within the animal kindgom and have reached a high peak of invertebrate 
evolution." Insects have evolved very rapidly, compared with other 
major groups, and have adapted to a wide variety of ecological niches. 
Thus, it would be difficult to include insects among "lower" eukaryotes. 
Appended Attachments 2 and 3, are two evolutionary charts showing the 
independent evolution of insects and vertebrates; insects are not 
"lower" than vertebrates; perhaps the guidelines should be modified, 
because the term "lower" is not clear regarding complexity of organ- 
ization or of evolution. With respect to the possibility of a risk 
to man, "shotgun" experiments involving the DNA of insects are 
permitted with EK1. In K. G. V. Smith’s, Insects and other Arthropods 
of Medical Importance (British Museum, London, 1973), a vector table 
lists insects and other arthropods involved in the transmission of 
organisms pathogenic to man. Pathogens carried by insects include 
bacteria, nematodes, protozoans, rickettsia, spirochetes, and viruses. 
Over 270 species of insects and arthropods are listed as vectors of 
more than one human pathogen. These known pathogens require higher 
containment. However, because of the multitide of insect species 
and of their symbiotic arrangements with microorganisms, it is 
* Many insects have symbionts, such as protozoans, which aid with the 
digestion of food. 
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