Page 37 of Attachment E 
recognition purposes. The object of this test would be to assess the 
probability of plasmid mobilization rather than self-specified transfer. 
We feel that the feeding experiments should be earned out in a 
limited number of laboratories (probably not more than 10-12), chosen to 
achieve two main objectives; first, there should be a number of 
laboratories distributed throughout the world in such a way that one 
might assess the impact of dietary factors on excretion and transfer. 
Such labs might be expected to be predominantly in the developing 
world. The second group of laboratories should be representative of 
those in developed countries where substantial amounts of genetic 
engineering are already in progress. 
The monitoring experiments — as opposed to those concerned with 
feeding — would be confined to laboratories already carrying out 
genetic engineering experiments. Their numbers might well be more 
extensive than in those doing the feeding experiments. In this case, the 
test would amount only to plating faecal samples from the workers on 
appropriate agar to detect the strains and plasmids used for ex- 
perimental work. For this, COGENE would have to encourage the labs 
concerned to mark their host strains in such a way that they could be 
recognized easily; and it seems possible that COGENE might give some 
advice as to how this might be done. 
We gave some thought to the possibility of trying to set up ex- 
periments in which the excretion of vector plasmids might be followed 
in those doing genetic engineering. However, we find it hard to propose 
anything that would be likely to be accepted willingly in the labs con- 
cerned. The use of tetracycline resistance in vectors already causes 
difficulties for monitoring because of the prevalence of tetracycline 
resistant E. coli in man at the present time; and we suspect that the use 
of antibiotic resistance markers in vectors is likely to be abandoned 
gradually in favour of other markers with less undesirable properties 
anyway. In view of this, we would not want to encourage the insertion of 
antibiotic resistance markers in vectors merely for the monitoring 
purposes. Perhaps the best plan in this case would be to watch 
developments and make proposals when the selective markers finally 
adopted for use in vectors have become clearer. 
There are two general (unconnected) points that are worth making. 
First, we do not feel that it is COGENE's role to validate hosts and 
vectors: that must be the responsibility of national committees. 
Secondly, we have made no proposals about setting up experiments 
with cloned eukaryotic DNA at this stage. Perhaps these could come 
later. 
Finally, we think that a successful organization and completion of 
these tests will need a small steering group to oversee them. This group 
could also — in due course — be responsible for organizing the 
publication of the results of the tests. Unless this is done, the whole 
exercise will have been pointless”. 
March 1977 
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