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(h) synthesize the protein in sufficient quantity to be deleterious 
to the infected organism. 
The overall probability of a detrimental effect resulting from the formation 
of a harmful protein is then equal to the product obtained by multiplying 
together the probability of each event, (a) through (h). 
In those cases where the foreign DNA itself might be the cause 
of undesirable effects, another set of events must be considered. Where 
the foreign DNA is presumed to increase the pathogenicity of the initial 
host cell or virus, the inserted DNA must-- 
(i) impart a selective advantage for growth to the carrier of the 
recombinant DNA as compared with the original cell or virus, 
(j) alter the metabolism of the carrier so that it becomes 
disease -producing. 
The overall probability of a detrimental elfect by this mechanism is 
then equal to the product obtained by multiplying together the probabilities 
of events (a) through (e) times (i) through (j). 
In the case where the foreign DNA is presumed to cause undesirable 
effects by virtue of its transfer out of the original recipient and reinsertion 
into cells of another species, the DNA must-- 
(k) leave the original recipient without being destroyed, 
(l) survive transfer to another cell, 
(m) become associated with the other cell in a stable manner, 
either as an independent element or by natural recombination. 
The overall probability of an undesirable effect arising by means of 
the secondary transfer mechanism is equal to the product obtained 
by multiplying together the probabilities of events (a) through (e) and 
(k) through (m). 
