However, the Falmouth conference of last year has been used as the 
basis for downgrading the containment requirements for cloning foreign 
DNA in l. col i . This revision has been proposed without waiting for the results 
of experiments now in progress, designed under contract to the NIH to test 
an assumption on which the revision is based: namely, that the EK1 and EK2 
strains of E. col i cannot escape from the laboratory by the usual routes. 
Recently, unexpected results have shown that the EK2 strain can survive 
spillage much better than had been anticipated. This indicates that caution 
is still in order, at least until the full results of the study become avail- 
able in a year or so. It seems to us appropriate that the scientific data on 
this safety question be evaluated before rather than after giving hundreds of 
laboratories around the country the go-ahead to lower their precautions. 
Another closed meeting, held at Ascot this year, serves as the ostensible 
basis for the drastic downgrading of containment requirements for recombinants 
involving animal virus DNA , including tumor viruses. Actually the conference 
reportedly recommended P2 containment, but an American subgroup subsequently 
met and opted for PI and EK1. Now just as an aside, let no one suppose that 
PI actually represents "containment." PI and even P2 levels of precaution 
may prevent massive accidents but they simply cannot prevent ultimate escape 
from the laboratory. An experiment bearing on the safety of escaped viral 
recombinant DNA has already been carried out - the Rowe-Martin risk assess- 
ment experiment with Polyoma DNA. > 
<; Somehow the results have never been published, but they are reported to 
show that a recombinant plasmid carrying viral DNA can be infectious in mammals. 
Thus, the insertion of such recombinant plasmids into E_. col i gives the virus 
an entirely new route of attack which could be dangerous even if the coli 
itself did not survive after entering the animal or man. The new route might 
than 
even prove to be more efficacious/the normal mode of infection by the virus. 
[ 375 ] 
