16 
■lII-C-2-a-(l) . Reoonbinant DMA molecules containing no more than two- 
thirds of the genome of any invertebrate virus (all viruses from a single 
Family (36) being considered identical (50)] may be propagated and 
maintained in cells in tissue culture using Pi containment. For such 
experiments, it must be shown that the cells lack helper virus for the 
specific Families of defective viruses being used. The DNA may contain 
fragments of the genomes of viruses from more than one Family but each 
freigment must be less than two-thirds of a genome. 
■III-C-2-a-(2). Reoombin^mts with less than two- thirds of the genome of 
any invertebrate virus may be rescxjed with helper virus using P2 contain- 
ment unless it is classified by the CDC as a class 3 agent (1) in which 
case P3 containment is required. 
■III-C-2-a-(3) . Eicperiments involving the use of other whole or defec- 
tive virus genomes to propagate DNA sequences from prokaryotic or 
eukaryotic organisms (and viruses), or as vectors to transform non- 
permissisive cells, will be evaluated by NIH on a case-by-case basis 
[45] and will be conducted under the prescribed physic^d and biological 
containment conditions. (See Section IV-E-l-b-(3)-(c) . )" 
■NIH will edso review on a case-by-case basis (45] edl experiments 
involving the use of virus vectors in ^tf 1 imals ^tf>d will prescribe the 
physic^d and biological containment conditions appropriate for such 
studies. (See Section IV-E-l-l>-(3)-(c) . )" 
V. HEQUEST TD CLONE SUBCPOUC SEXXP7TS OF RIFT VALLEY FEVER VIRUS 
Bems introduced the request (tabs 1030, 1035/4, 1038) of Molecular 
Genetics, Inc., of Minnetonka, Minnesota, to clone, ixxier PI containment 
conditions, segments of the Rift Valley Fever Virus genome. The objective is 
to clone the segments which encode the virus' antigenic determin^u^ts. The 
work «(Ould be performed in collaboration with the U.S. Army Medical Research 
Institute of Infectious Diseases, Fort Detrick, Maryland. 
Dr. Bems said Rift Valley Fe^^r Virus is a najor problem in cattle in Africa. 
The virus may have recently extended its range into Egypt and the Sinai 
Peninsula. Wbrk with the virus in the united States is prohibited by the 
U5DA, except under special conditions. In addition to being a significant 
agricultural problem, the virus may be transmitted to hixnans. 
The virus itself is a negative stranded RNA virus. Such viruses are not 
infectious when purified as the conplementary strand is needed to function as 
a messenger. The Rift Valley Fever Virus genome is segmented; the genome is 
composed of three separate pieces of PNA. The investigators propose to work 
with one of the three segments, the so-called "M" or mediim sized segment 
which codes for those of the virus' antigenic determinants that elicit 
neutralizing antibodies. He said that the issues are comparable to those 
( 207 ] 
