Issue: Final
Date: November 2009
Page: 8 of 8 /
Guidance to completing the Genetic Modification of Micro-organisms (GMM) Risk Assessment
…No person shall undertake any activity involving genetic modification of micro-organisms unless… a suitable and sufficient assessment of the risks… to human health and the environment has been carried out (Regulation 6 of the Genetically Modified Organisms (Contained Use) Regulations 2000.
The Genetically Modified Organisms (Contained Use) Regulations 2000 and the Environmental Protection Act 1990 (EPA) require that suitable and sufficient assessment of the risks to human health and the environment be carried out for activities involving the genetic modification of organisms. The primary role of the risk assessment is to determine the appropriate control measures that are needed to afford maximum protection to both human health and the environment. This, in turn, will determine the notification requirements for the proposed work.
This guidance document is based on the Scientific Advisory Committee on Genetic Modification (SACGM). Full SACGM guidance is available via http://www.hse.gov.uk/biosafety/gmo/acgm/acgmcomp/, in particular Part 2 for risk assessment to human and animal health and Part 4 for plant health.
The final risk assessment must contain enough background and detail to ensure that a reviewer with limited understanding of the precise nature of the work will not require further information to comprehend the nature of any hazards. All feasible potential hazards should be acknowledged and information should be based on established scientific knowledge where available, duly referenced. Any uncertainty should be acknowledged and dealt with appropriately – lack of evidence does not equal lack of hazard.
It is a legal requirement for risk assessments to be kept for 10 years after the work has ceased. Storage of materials is classed as active work.
For a glossary of abbreviations used in the form please go to the end of this guidance.
Guidance on specific questions
Short description of project aim, rationale, work procedures
Outline and justify context of the research and main procedures, especially where unusual methods are employed. If hazardous (for definition of ‘hazardous’ in this context see SACGM guidance) biological agents are used please give reason for not using less hazardous agents. NB: A comprehensive list of all hazardous agents is not required in this box.
Details of insert(s) and host/vector system(s):
Provide details for each insert, including short functional description and originating organism/strain. In which form are these inserts received on site (e.g. live culture; frozen tissue; naked DNA complete genome; naked DNA PCR product).
An adequate overview of the different types of GMM that will be constructed must be provided. Host/vector systems must be given in sensible groupings with only those combinations given which will actually be produced during the work.
Provide details of host strains with relevant disabling mutations. These can be found in Maniatis (J. Sambrook, E. F. Fritsch and T. Maniatis (1989) Molecular Cloning, A Laboratory Manual) or the supplier information data sheets. Where strains are derived from a common originating strain only the latter needs to be detailed. For example ‘E. coli BL21 and derivatives’ will include strains like Rosetta.
Details of vectors should be provided in a similar way. For example, ‘pBR322 and derivatives’ will include P426 and pPIC 9k.
Derivatives which have disablements restored or have added functionality which may convey a hazard must be detailed specifically.
Where a project includes multiple hosts for genetic material, e.g. cloning of genes into bacteria and then into mammalian cells for further studies, all individual GMMs to be created must be listed.
If relevant, a diagrammatic representation of vectors/inserts can be attached to this form.
Overall nature of intended GMM
SACGM recommends you complete the assessment for the most at-risk group (either human health or environment) first.
Guidance on Part A – Risk Assessment for Human Health
The objective is to identify all plausible hazards to human health and then to assess the likelihood and potential severity of the consequences, should the hazards be realised.
Answers should never be a stand-along ‘yes’ or ‘no’. Always give reasoning and explanations and where possible back this up with scientific evidence and references.
A1. Mechanisms by which the GMM might pose a hazard to health
This section involves identifying those features of the GMM that have the potential to cause harm and the mechanisms by which these hazards could be realised.
Factors to be considered include pathogenicity of the recipient microorganism, the properties of the sequences to be inserted and the final GMM. Areas of uncertainty must be highlighted.
· What are the hazards associated with the recipient strain(s)?
For example, for pathogens give a short description of disease symptoms, transmission route, available prophylaxis etc.
Particular care must be given to the assessment of GMMs that have the potential to enter human cells or establish an infection in human hosts.
Are any disabling mutations likely to be complemented (e.g. by insert/vector combinations or recombination with wild type) or reversed by mutation? A consequence of a reversion event in an attenuated or disabled recipient could be the generation of a pathogenic strain that expresses the inserted gene.
· What hazards are associated with the inserted genetic material?
For example from which organism / strain does it originate; is the insert potentially harmful and in what form can it cause harm (e.g. toxins, cytokines, growth factors, allergens, hormones or oncogenes – consider kinetics and expected level of expression; consequences of exposure). Inserted genes can also encode pathogenicity or virulence in other ways (invasion, surface determinants such as pili, LPS and capsule affecting infectivity and virulence of the bacterial host).
· Have the pathogenic traits of the recipient strain been altered?
Many modifications will not involve genes with products that have activities that will be directly harmful, but adverse effects may nevertheless arise as the result of exacerbation or alteration of existing pathogenic traits.
E.g. describe modifications; altered virulence; altered tissue tropism or host range; altered response to prophylaxis; any modifications affecting the infectivity or virulence of the host e.g. modified regulatory components may have unforeseen ramifications; any modifications altering susceptibility to the immune system (e.g. expressing interleukin 4 may inhibit the appropriate immune response to certain pathogens).
· Could the GMM or other organisms acquire harmful sequences?
There are many mechanisms by which sequences may be transferred between micro-organisms and the factors that affect the frequency of such events and the likelihood of a harmful consequence are complex. Such issues must be carefully considered in the risk assessment. During the hazard identification process, it is important to consider the potentially harmful consequences of sequences inserted into a GMM being transferred to other organisms, or that the GMM itself may acquire sequences that increase its pathogenicity.
‘Harmful’ in this sense is anything that is either inherently harmful (e.g. toxin) or could render a pathogen more harmful or with a selective advantage (e.g. if a modified insert were to recombine back into a wild type pathogen. Would the inserted sequence give an advantage to naturally occurring pathogens (e.g. drug-resistance markers give a selective advantage and are classed as ‘harmful sequences’ if mobilised to pathogens – therefore non-mobilisable plasmids should be used as a general rule)?
The longer the microorganism can survive outside lab conditions the more chance there is for a transfer event (e.g. some E coli K12 can survive for up to several days in the gut and for similar lengths of time in the environment). Transformation and conjugation involving plasmid DNA could result in transfer of harmful sequences between bacteria.
If the wild type strain of the GMM is handled in the same lab this should be taken into consideration. It is usually safest to insert sequences close to a disabling mutation so that if recombination were to occur both would be lost at the same time – justify if a different insertion site is chosen.
A.2 Likelihood that the GMM will be a risk to human health and safety
In this section the likelihood of the (theoretical) hazards identified in section A.1 being manifested should be realised, assessed and their potential impact understood.
· Likelihood: Could the GMM establish an infection in vivo and how efficient would it be?
Consider the overall fitness of the GMM (ability to establish an infection, how efficient that infection would be and its ability to spread within a host or through a community) and the probability that rare events like mutation, recombination or gene transfer may occur (published data of numerical frequencies may exist, e.g. comparing the frequency of transfer of mobilisable, mobilisation defective and non-transferable plasmids). Is there selective pressure for deletion of the modified sequences or is there a vital sequence nearby preventing this?
· How severe might the consequences be?
For example consider the severity of harm to an individual and the severity of secondary spread to the wider community; consider availability of prophylaxis. Consider if there are any particular groups of individuals who might be at higher risk than others and whether they are likely to come into contact with the work.
· Containment level needed to sufficiently protect human health
At this stage the setting of a minimal containment level to protect human health is only provisional and estimated to protect those who come into contact with the GMM. Consider the containment level necessary to control the risk of the recipient micro-organism and make a judgement about whether the proposed modification will result in a GMM that is more hazardous, less hazardous or approximately equivalent.
Guidance on Part B – Risk Assessment for the Environment
There is a requirement under both the Genetically Modified Organisms (Contained Use) Regulations 2000 and the Environmental Protection Act 1990 to consider risks to the environment. The objective of this section is to identify all plausible hazards to the environment (animal, plant and microbial) and to determine the likelihood and the possible consequences of an accidental release of a GMM from containment into the environment (including waste disposal, equipment failure and human spread).
Consider the local as well as the wider environment.
GMMs with the potential to infect or colonise animals and plants are of primary concern.
If a GMM is incapable of infecting or impacting on any species other than humans this should be stated here with supporting evidence.
B1. Mechanisms by which the GMM might pose a hazard to the environment
This section focuses on the identification of those features of the GMM that have the potential to cause harm to the environment and the mechanisms by which theses hazards could be realised.
· Hazards associated with the recipient strain(s)
Consider pathogenicity, infectivity, toxicity, virulence, allergenicity, colonisation, parasitism, symbiosis and competition. How does the proposed modification affect these traits? Take account of the DEFRA (SAPO) classification of animal pathogens: www.defra.gov.uk/animalh/diseases/pathogens/classification.htm. GMMs based on such pathogens may require DEFRA licenses to handle (under SAPO) or import (under IAPO). Also consider the DEFRA Plant Health Division for plant pathogens: http://www.defra.gov.uk/planth/ph.htm .
· Has the stability or survivability of the recipient been altered?
Consider modifications compared to wild type; longevity inside / outside the host. If the GMM is short-lived this normally provides safe ‘biological containment’. Consider viability within organisms as well as in soil, water or other sites, vegetative as well replicating stage.
· Hazards associated with genetic inserts – Does the inserted gene pose a risk to other organisms?
GMMs might be a hazard to the environment by virtue of the properties inherent to the genetic insert, even if the recipient micro-organism poses no specific risk, for instance pesticidal genes.
· Hazards arising from the alteration of traits in the GMM
For example, consider alteration of stability or survivability (enhanced resistance to oxidative stress, UV, temp fluctuations or dehydration); pathogenicity or infectivity (altered susceptibility to host immune systems); tissue tropism or host range.
· Could the GMM or other organisms in the environment acquire harmful sequences?
Consider exchange of genetic material with other strains/pathogens in both directions, from GMM to environment but also from environment to GMM, making it more harmful e.g. E coli K12 during persistence in gut, especially under bacterial stress conditions).
Can any disabling/attenuating mutations be reverted or complemented? In particular, assess the possibility of sequence mobilisation in bacteria (e.g. through [re-]mobilisable plasmid vectors).
B2. Likelihood that the GMM will be a risk to the environment
In this section the chances of the hazards identified in section B1 being realised should be evaluated and understood.
· What is the likelihood that the hazard(s) will be manifested?
Where the likelihood of harm is poorly understood, a precautionary approach should be adopted until evidence to the contrary has been obtained.
Estimate the risk as high, medium, low or negligible, with justification.
· What will be the consequences if the hazard is realised?
Even if a quantitative estimate is not possible, a qualitative appraisal of the impact on other species or ecosystems should be possible. Consequences could be described as severe, modest, minor or negligible, with justification. Please note that even if the likelihood of occurrence is low the potential consequences may be severe.
· Containment level needed to protect the environment
This requires a judgement as to whether the measures required for the recipient strain in the appropriate table of containment measures in Schedule 8 of the GMOs (Contained Use) Regulations 2000 are also appropriate for the GMM. If some measures are not needed or extra measures are required the containment level should be adjusted accordingly. Requiring a measure listed as a higher containment level will automatically upgrade the final containment level for the work.
Guidance on Part C. Review of Procedures and Control Measures
The requirements of the final containment level must be sufficient to control al the potential harmful properties of the GMM and offer sufficient protection for both human health and the environment. Any non-standard operations increasing the risk of exposure or likelihood of release must be taken into account to decide whether additional containment and control measures are required.