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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Asilomar Conference on Recombinant DNA | 2/3 | https://en.wikipedia.org/wiki/Asilomar_Conference_on_Recombinant_DNA | reference | science, encyclopedia | 2026-05-05T06:59:59.280945+00:00 | kb-cron |
=== Recommendations given === The Asilomar Conference also gave recommendations for matching the types of containment necessary for different types of experiments. These recommendations were based on the different levels of risk associated with the experiment, which would require different levels of containment. These levels were minimal, low, moderate and high risk. The minimal risk level of containment was intended for experiments in which the biohazards could be accurately assessed and were expected to be minimal. Low risk containment was appropriate for experiments that generated novel biotypes but where the available information indicated that the recombinant DNA could not either alter appreciably the ecological behavior of the recipient species, increase significantly its pathogenicity or prevent effective treatments of any resulting infections. The moderate risk level of containment was intended for experiments in which there was a probability of generating an agent with a significant potential for pathogenicity or ecological disruption. High-risk containment was intended for experiments in which the potential for ecological disruption or pathogenicity of the modified organism could be severe and thereby pose a serious biohazard to laboratory personnel or to the public. These levels of containments, along with the previously mentioned safety measures, formed the basis for the guidelines used by investigators in future experiments that involved the construction and propagation of recombinant DNA molecules using DNA from prokaryotes, bacteriophages and other plasmids, animal viruses and eukaryotes.
=== Recommendations applied to experiments === For prokaryotes, bacteriophages and other plasmids, experiments could be performed in minimal risk containment facilities when the construction of recombinant DNA molecules and their propagation involved prokaryotic agents that were known to exchange genetic information naturally. For experiments involving the creation and propagation of recombinant DNA molecules from DNAs of species that ordinarily did not exchange genetic information and generate novel biotypes, the experiments were to be performed in at least in a low risk containment facility. If the experiment increased the pathogenicity of the recipient species or result in new metabolic pathways in species, then moderate or high-risk containment facilities were to be used. In experiments where the range of resistance of established human pathogens to therapeutically useful antibiotics or disinfectants was extended, the experiments were to be undertaken only in moderate or high-risk containment facilities. When working with animal viruses, experiments that involved the linkage of viral genomes or genome segments to prokaryotic vectors and their propagation in prokaryotic cells were to be conducted only with vector-host systems that had demonstrated restricted growth capabilities outside the laboratory and in moderate risk containment facilities. As safer vector-host systems became available, such experiments could be performed in low risk facilities. In experiments designed to introduce or propagate DNA from non-viral or other low risk agents in animal cells, only low risk animal DNA could be used as vectors and the manipulations were to be confined to moderate risk containment facilities. With eukaryotes, attempts to clone segments of DNA using recombinant DNA technology from warm-blooded vertebrates genomes were to be performed only with vector-host systems that had demonstrably restricted growth capabilities outside the laboratory and in a moderate risk containment facility. This was because they potentially contained cryptic viral genomes that were potentially pathogenic to humans. However, unless the organism made a dangerous product, recombinant DNAs from cold-blooded vertebrates and all other lower eukaryotes could be constructed and propagated with the safest vector-host system available in low risk containment facilities. Additionally, purified DNA from any source that performed known functions and was judged to be non-toxic could be cloned with available vectors in low risk containment facilities.
=== Prohibited experiments === In addition to regulating the experiments that were conducted, the guidelines also forbade the performance of other experiments. One such experiment was the cloning of recombinant DNAs derived from highly pathogenic organisms. In addition, neither the cloning of DNA containing toxin genes, nor large scale experiments using recombinant DNAs that were able to make products that were potentially harmful to humans, animals or plants were allowed under the guidelines. These experiments were banned because the potential biohazards could not be contained by the then current safety precautions.