Suggested categorisations for some txpical experiments in Categories I, II, III 
& IV 
(These examples all assume standard biochemical manipulations) 
Source of nucleic acid 
Specification 
of nucleic 
acid sequence 
Vector/ Host System 
Category 
Mammals 
Random 
Phage or plasmid bacteria, 
not disabled 
IV 
Random 
Phage or plasmid bacteria, 
disabled 
III 
Purified* 
Phage or plasmid bacteria, 
not disabled 
III 
Purified* 
Phage or plasmid bacteria, 
disabled 
II 
Amphibians and reptiles 
Random 
Phage or plasmid bacteria, 
not disabled 
III 
Random 
Phage or plasmid bacteria, 
disabled 
II 
Purified* 
Phage or plasmid bacteria, 
not disabled 
II 
Purified* 
Phage or plasmid; bacteria, 
disabled 
I 
Plants and invertebrates 
and lower eukaryotes 
Random 
Phage or plasmio/bacteria, 
not disabled 
II 
Random 
Phage or plasmid'bactena, 
disabled 
I 
Purified* 
Phage or plasmid bacteria, 
not disabled 
I 
Mammals 
Amphibians and reptiles 
Birds 
Random 
Virus capable of infecting 
man or growing in tissue 
culture cells 
IV 
Purified* 
Virus capable of infecting 
man or growing in tissue 
culture cells 
III 
Viruses pathogenic to 
vertebrates 
Random 
Phage or plasmid bacteria, 
disabled 
IV 
Purified* 
Phage or plasmid, 'bacteria, 
disabled 
III 
Animal viruses, non- 
pathogenic to man 
Random 
Phage or plasmid/bacteria, 
disabled 
II 
• The term “purified” means fractions with little chance of including any unrecognised 
extraneous sequences (see paragraph 2 6 it. It is of course possible to have sequences selected 
because of their pathogenicity and these would raise the level of containment required. 
IV-11 
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