BIOSAFETY LABORATORY MANUAL
The National Biosafety Management Agency (NBMA) recognizes safety in the practice of modern biotechnology in containment facilities. Biosafety Laboratory manual guides Scientists in the correct laboratory work ethics. Biosafety Laboratory manual serves as the national code of practice for the safe handling of Genetically Modified Organisms (GMOs) in laboratories.
This manual has been developed, with the view of reviewing on standard operational basis, for handling organisms in all BL2 laboratories which are unlikely to pose serious hazards to laboratory workers, the community, livestock or the environment. The laboratory facilities contained herein are designated as basic – Biosafety Level 2 based on a composite of the design features, containment facilities, practices and operational procedures.
All agents in Biosafety Level 2 laboratory have been assigned to Risk Group 2 and generally require Biosafety Level 2 practices and procedures for safe conduct of work. The assignment of biosafety level for specific work to be carried out in this laboratory is driven by professional judgement based on a risk assessment. This laboratory is appropriate to provide the necessary degree of work, following its provision for state of the art equipment in GMO analysis.
However, the availability of state-of-the-art equipment in a containment facility does not guarantee safety during laboratory operations. It is therefore necessary to adhere to all laboratory safety measures detailed herein to ensure safe conduct of experiments.
For the purposes of this manual, the guidance and recommendations are given as minimum requirements pertaining to Level 2 laboratories.
The guidelines for Basic Biosafety Level 2 presented here are comprehensive and detailed, as they are fundamental to this level of Biosafety laboratory.
This code is a listing of the most essential laboratory practices and procedures that are basic. This laboratory has adopted a safety or operations manual that identifies known and potential hazards, and specifies practices and procedures to eliminate or minimize such hazards. Specialized laboratory equipment is a supplement to but can never replace appropriate procedures. The most important concepts are listed below:
Laboratory Working Areas
Essential Biosafety Equipment
Equipment available in Biosafety Level 2 laboratory include the following:
Equipment such as autoclaves and biosafety cabinets must be validated with appropriate methods before being taken into use. Recertification should take place at regular intervals, according to the manufacturer’s instructions.
Waste is anything that is to be discarded. In this laboratory, decontamination of wastes and their ultimate disposal are closely interrelated. In terms of daily use, all contaminated materials will require actual removal from the laboratory or destruction. Glassware, instruments and laboratory clothing may be reused or recycled. Appropriate waste containers and labelling should be maintained in the laboratory. The overriding principle is that all infectious materials should be decontaminated, autoclaved or incinerated within the laboratory.
The principal questions to be asked before discharge of any objects or materials from this laboratory should include:
Steam autoclaving is the preferred method for all decontamination processes. Materials for decontamination and disposal should be placed in containers, e.g. autoclavable plastic bags that are colour-coded according to whether the contents are to be autoclaved and/or incinerated. Alternative methods may be envisaged only if they remove and/or kill microorganisms.
The use of safety equipment is no assurance of protection unless the operator is trained and uses Standard Operating Procedure (SOP). Equipment should be tested regularly to ensure its continued safe performance. Some safety equipment available in Biosafety laboratory includes:
A pipetting aid must always be used for pipetting procedures. Mouth pipetting is strictly forbidden in the laboratory. The most common hazards associated with pipetting procedures are the result of mouth suction. Oral aspiration and ingestion of hazardous materials have been responsible for many laboratory-associated infections but pathogen ingestion can be prevented by the use of pipetting aids. Pipettes with cracked or chipped suction ends should not be used as they damage the seating seals of pipetting aids and so create a hazard.
Personal protective equipment and clothing may act as a barrier to minimize the risk of exposure to aerosols, splashes and accidental inoculation. The clothing and equipment selected is dependent on the nature of work performed. Protective clothing should always be worn when working in the laboratory. Before leaving the laboratory, protective clothing should be removed, and hands should be washed. Some personal protective equipment that must be used in the laboratory include:
Laboratory coats should be worn fully buttoned. Aprons may be worn over laboratory coats or gowns where necessary to give further protection against spillage of chemicals or biological materials such as culture fluids. Laundering services should be provided at or near the laboratory.
Laboratory coats, gowns, coveralls, or aprons should not be worn outside the laboratory areas.
The choice of equipment to protect the eyes and face from splashes and impacting objects will also depend on the activity performed. Safety spectacles do not provide for adequate splash protection even when side shields are worn with them. Goggles for splash and impact protection should be worn over normal prescription eye glasses and contact lenses (which do not provide protection against biological or chemical hazards).
Goggles, safety spectacles, or face shields should not be worn outside the laboratory areas.
Contamination of hands may occur when laboratory procedures are performed. Hands are also vulnerable to “sharps” injuries. Disposable microbiologically approved latex, vinyl or nitrile surgical-type gloves are used widely for general laboratory work, and for handling infectious materials.
Gloves should be removed and hands thoroughly washed after handling infectious materials, working in a biosafety cabinet and before leaving the laboratory. Used disposable gloves should be discarded with laboratory wastes. Stainless steel mesh gloves should be worn when there is a potential exposure to sharp instruments e.g. during dissections. Such gloves protect against slicing motion but do not protect against puncture injury.
Gloves should not be worn outside the laboratory areas.
Respiratory protection may be used when carrying out high-hazard procedures (e.g. cleaning up a spill of infectious material). The choice of respirator will depend on the type of hazard(s).
It is important that the respirator filter is fitted in the correct type of respirator. To achieve optimal protection, respirators should be individually fitted to the operator’s face and tested. Fully self-contained respirators with an integral air supply provide full protection. Some single-use disposable respirators have been designed for protection against exposures to biological agents.
Respirators should not be worn outside the laboratory areas.
Human error, poor laboratory techniques and misuse of equipment cause the majority of laboratory injuries and work-related infections. A compendium of technical methods that are designed to avoid or minimize the most commonly reported problems of this nature is highlighted.
Sample containers may be of glass or preferably plastic. They should be robust and should not leak when the cap or stopper is correctly applied. No material should remain on the outside of the container. Containers should be correctly labelled to facilitate identification. Sample request or specification forms should not be wrapped around the containers but placed in separate, preferably, waterproof envelopes.
To avoid accidental leakage or spillage, secondary containers, such as boxes, should be used, fitted with racks so that the sample containers remain upright. The secondary containers may be of metal or plastic, should be autoclavable or resistant to the action of chemical disinfectants, and the seal should preferably have a gasket. They should be regularly decontaminated.
Personnel who receive and unpack samples should adopt standard precautions particularly when dealing with broken or leaking containers. Sample containers should be opened in a biosafety cabinet. Disinfectants should also be available.
In pipetting, the following precautions should be adopted:
The biosafety cabinet does not protect the operator from spillage, breakage or poor technique. Therefore, care must be taken while working in a biosafety cabinet.
The following precautions are necessary:
Satisfactory mechanical safety performance is a prerequisite in the use of centrifuges in the laboratory. In the use of centrifuges therefore, the following precautions should be adopted:
A basic knowledge of disinfection and sterilization is essential for biosafety in the laboratory. It is important to understand the rudiments of cleaning prior to disinfection. The requirements for decontamination depend on the type of experimental work and the nature of materials being handled in the laboratory.
Cleaning is the removal of dirt, organic matter and stains. Cleaning includes brushing, vacuuming, dry dusting, washing or damp mopping with water containing soap or detergent. Dirt, soil and organic matter can affect the results of analysis.
Pre-cleaning is necessary to achieve proper disinfection or sterilization. Pre-cleaning must be carried out with care to avoid exposure to infections.
Materials chemically compatible with disinfectants to be applied later must be used. It is quite common to use the same disinfectant for pre-cleaning and disinfection.
Many types of chemicals can be used as disinfectants and/or antiseptics. As there is an ever-increasing number and variety of commercial products, formulations must be carefully selected for specific needs.
Some disinfectants can be harmful to humans or the environment. They should be selected, stored, handled, used and disposed of with care, following manufacturers’ instructions. For personal safety, gloves, aprons and eye protection are recommended when preparing dilutions of disinfectants. Disinfectants are generally required for regular cleaning of floors, walls, equipment and furniture.
Proper use of disinfectants will contribute to workplace safety. The number of disinfectants to be used should be limited to reduce environmental pollution
Saturated steam under pressure (autoclaving) is the most effective and reliable means of sterilizing laboratory materials. For most purposes, the following cycles will ensure sterilization of correctly loaded autoclaves:
While loading autoclaves, materials should be loosely packed in the chamber for easy steam penetration and air removal. Bags should allow the steam to reach their contents. In the operation of autoclaves, the following precautions must be adhered to:
Incineration is useful for disposing of laboratory waste, with or without prior decontamination. Proper incineration requires an efficient means of temperature control and a secondary burning chamber. Ideally, the temperature in the primary chamber should be at least 800°C and that in the secondary chamber at least 1000°C.
Materials for incineration, even with prior decontamination, should be transported to the incinerator in bags, preferably plastic. It is worth noting that the efficient operation of an incinerator depends heavily on the right mix of materials in the waste being treated.
Autoclaved waste should be disposed of by off-site incineration or in approved landfill sites.
A written contingency plan for dealing with laboratory accidents is a necessity in any Biosafety laboratory.
The contingency plan should provide operational procedures for:
In the development of this plan the following items should be considered for inclusion:
The affected individual should remove protective clothing, wash the hands and any affected area(s), apply an appropriate skin disinfectant, and seek medical attention as necessary. The cause of the wound and the organisms involved should be reported. Appropriate and complete medical records should be kept.
Protective clothing should be removed and medical attention sought. Identification of the material ingested and circumstances of the incident should be reported. Appropriate and complete medical records should be kept.
All persons should immediately vacate the affected area and any exposed persons should be referred for medical advice. The laboratory Head should be informed at once. No one should enter the room for an appropriate amount of time (at least 1 hour), to allow aerosols to be carried away and heavier particles to settle. Entrance should be delayed for at least 24 hours following the absence of a central air exhaust system.
Signs should be posted indicating that entry is forbidden. After the appropriate time, decontamination should proceed, supervised by the laboratory Head. Appropriate protective clothing and respiratory protection should be worn.
If a breakage occurs or is suspected while the machine is running, the motor should be switched off and the machine left closed (e.g. for 30 mins) to allow settling. If a breakage is discovered after the machine has stopped, the lid should be replaced immediately and left closed (e.g. for 30 mins). In both instances, the Head of the laboratory should be informed. Thick rubber gloves covered, if necessary, with suitable disposable gloves, should be worn for all subsequent operations. Forceps, or cotton held in the forceps, should be used to retrieve glass debris. All broken tubes and glass fragments and the rotor should be placed in a noncorrosive disinfectant.
Unbroken, capped tubes may be placed in disinfectant in a separate container and recovered. The centrifuge bowl should be swabbed with the same disinfectant, at the appropriate dilution, and then swabbed again, washed with water and dried. All materials used in the clean-up should be treated as infectious waste.
All sealed centrifuge buckets should be loaded and unloaded in a biosafety cabinet. If breakage is suspected within the safety cup, the safety cap should be loosened and the bucket autoclaved. Alternatively, the safety cup may be chemically disinfected.
Fire and other services should be involved in the development of emergency preparedness plans. It is beneficial to arrange for these services to visit the laboratory to become acquainted with its layout and contents.
The telephone numbers and addresses of the following are displayed in this facility:
Modern biotechnology offers the opportunity to use living systems and organisms to develop, make or modify useful products or processes for specific use with the aim of improving living conditions and socio-economic development across the world. The engineered organisms or Genetically Modified Organisms (GMOs) are also referred to as Living Modified Organisms (LMOs).
GMOs are organisms such as bacteria, yeast, insects, plants, fish and mammals whose genetic materials have been altered using genetic engineering techniques.
GMOs have been applied in four major industrial areas, including medical, agriculture, industrial uses of crops and other products (e.g. biodegradable plastics, vegetable oil, biofuels), and environmental bio-remediation. The applications of GMOs can also be used to provide alternative approaches to addressing poverty- related challenges using widely applicable innovative tools at the community and national levels. In this respect, the use of GMOs in improving agricultural productivity has particularly been widely reported.
Currently in agriculture, existing genetically modified crops have traits such as pest resistance, herbicide tolerance, drought tolerance, increased nutritional value, or production of valuable goods such as drugs.
Despite the obvious advantages in the development, handling and use of plant GMOs for FFP, these GMOs are sometimes considered as alien species by critics, since they may have no defined geographical distribution in the natural environment until they are released from the generate sources. Concerns therefore arise as to whether their release could have harmful effects on living organisms, biodiversity and environmental safety (IUCN 2000). Also, concerns may be raised about food and feed safety such as altered composition, nutritional bio-availability and allergenic risks.
In order to address these concerns, the Cartagena Protocol on Biosafety adopted by the Conference of the Parties (COP) of the Convention on Biological Diversity (CBD) on 29th January 2000, sought to protect biological diversity from the potential risks posed by GMOs resulting from modern biotechnology.
The Cartagena Protocol on Biosafety (CPB) provides an Advance Informed Agreement (AIA) procedure that ensures that countries have the information necessary to make an informed decision before permitting the import and production of such organisms into their territory. The Protocol also establishes regulations for developing biosafety frameworks in member countries, as well as Biosafety Clearing House (BCH) to facilitate the exchange of information on GMOs for direct use for food, feed or processing.
In accordance with the CPB, Nigeria has developed a comprehensive biosafety framework with policy, administrative and regulatory instruments in place. This specifically includes the National Biosafety Policy and the National Biosafety Bill of 2006. The National Biosafety Bill was subsequently passed by the National Assembly and assented to by the President on the 18th of April, 2015 as the National Biosafety Management Agency Act 2015. The Act established the National Biosafety Management Agency in 2015, charged with the responsibility for providing regulatory framework, institutional and administrative mechanism for safety measures in the application of modern biotechnology in Nigeria with the view to preventing any adverse effect on human health, animals, plants and environment. The agency also develops capacity for biosafety risk assessment including testing and detection of GMOs.
In view of the above, Nigeria has developed these testing protocols to cover the following areas:
Nigeria has a vibrant local agricultural and horticultural sectors known for the production of local food crops and cash crops. The food crops include cereals (maize, millet, sorghum, rice, etc.), roots and tubers (yam, cassava, potato, cocoyam, etc.), fruits and vegetables (pepper, tomato, egg-plant, onion, carrot, cabbage, mango, orange etc.) and legumes and nuts (beans, soya beans, groundnuts, cashew nuts, etc.). Some major cash crops for export are: cocoa, shea butter, rubber, cotton and oil palm. Other exports include forestry resources such as timber, wood products and some wildlife.
Nigeria also imports various food crops and other plant resources. These include wheat, rice, tomatoes, cowpea, and soybean. The importation of plant resources, food, feed and products for processing is monitored and promoted by several regulatory agencies namely: National Agricultural Seed Council (NASC), Nigeria Customs Service (NCS), Nigeria Agricultural Quarantine Service (NAQS), National Agency for Food and Drug Administration and Control (NAFDAC) and Standards Organization of Nigeria (SON). With the enactment of the National Biosafety Management Agency (NBMA) Act 2015, all GMOs imported into the country are regulated by the NBMA.
Building capacity for testing and detection of GMOs is essential for reliable monitoring and evaluation of the safe development, handling, use, and trans-boundary movement. GMO testing capacity is critical to building confidence among scientists, regulators and the general public.
Below is a list of crops that have been modified by modern biotechnology using genetic engineering to generate plant GMOs with unique identifiers that can be tested by ELISA and/or PCR methods.
In the testing for GMOs in food and feed, it is important to have technical experts to ensure proper running of the laboratory, handling of samples and testing methodology. A few of such expertise are listed below:
Testing for GMOs requires the use of specific equipment, a few of which are listed below.
The general procedure that would be adopted for the detection of GMOs in the Biosafety laboratory include the following
Before the commencement of work, work place is cleaned with absolute ethanol to avoid contamination. If work is to be performed inside the Biosafety cabinet, the cabinet is wiped with absolute ethanol and the ultraviolet light turned on for some minutes. The UV light is then turned off after which, work commences.
During sample preparation, significant errors can occur in the absence of appropriate care. To avoid the occurrence of such errors, a representative composite sample must be crushed to appropriate particle size. Crushed sample must be thoroughly mixed prior to analysis. As sample preparation is a crucial step in the testing of GMOs, care must be taken to avoid sample carryover during grinding which is a potential source of error that can be introduced into the final result.
Three factors (quantity of DNA extracted, quality and purity of DNA) determine the success of DNA extraction. DNA extraction is often the most time-consuming step in DNA detection and can form a bottleneck for high throughput detection.
DNA isolation would involve a number of steps. First, chemical agents will be used to disrupt cells for the release of DNA into a solution. Second, proteins and other cellular components will be largely removed by a protein precipitation step after which DNA will be maintained in solution. Finally, DNA will be selected from most of the contaminants by precipitation in alcohol.
PCR is a technique for the amplification of a number of copies of a specific DNA sequence. PCR must be very sensitive to always amplify the sequence of interest if present so as to prevent false negative result, and highly selective to only amplify the intended target sequence to prevent false positive results.
Most GMOs currently approved worldwide contain any of the three genetic elements that can be targets for GMO screening. These elements are the Cauliflower Mosaic Virus (CaMV) 35S promoter, the NOS terminator from the soil bacterium, Agrobacterium tumefaciens and the Kanamycin resistance marker gene (NPTII). Naturally, these sequences occur in plants and soil microorganisms. A positive result therefore will not necessarily confirm presence of GMOs but will only suggest they are probable.
To confirm definitively the presence of a GMO, a sample with positive signal in 35S and/or NOS screening will be further analysed using a construct-specific or event-specific method. Alternatively, the sample could be further analysed for the presence of naturally occurring CaMV or A. tumefaciens infection.
The CaMV promoter is preferred above other potential promoters because it is a more powerful promoter than others and is not greatly influenced by environmental conditions or tissue types. CaMV has two Promoters 19S and 35S, of these two the 35S promoter is most frequently used in biotechnology because it is most powerful. Where samples are recorded in large numbers, protein immunoassays would be utilized for testing.
The success of PCR amplification is assessed by agarose gel electrophoresis at 94 Volts for 60 seconds by observing the following procedure.
100 mL of Tris–acetate–EDTA (TAE) solution would be mixed with 1g of agarose in a conical flask. The mixture will be heated for one minute followed by cooling while it will constantly be shaken to prevent solidification on one side of the mixture. On the completion of cooling, SYBR Green I (SG) nucleic acid stain will be added to the mixture after which, the mixture will be poured into a flat tray and allowed to set. While still in liquid form, four combs will be placed astride the tray to form wells which following gel setting would form the wells. Individual wells will be loaded with the PCR product and gel loading buffer. The first wells of gel will be filled with ladder standard solution. Electrophoresis of the gel will follow after which the DNA in the gel will be visualized under an ultraviolet illumination
Immunological analysis, or immuno-analysis for short, is a GMO testing method that detects proteins. Currently, there are two types of GMO tests that use this method: The Strip Test and ELISA Methods.
This is a rapid antibody-based method used for measuring GMO protein in unprocessed materials such as seed, grain, or leaves. This method is appropriate for qualitative or semi-quantitative testing of GMOs. The method is suitable for field testing.
This is a rapid antibody-based method used for measuring GMO protein in unprocessed materials such as seed, grain, or leaves. ELISA is appropriate for qualitative or quantitative testing and is performed in a laboratory setting. For insect resistance analysis, Near Infrared Spectroscopy can be used.
Near Infrared Spectroscopy uses spectral properties of sample in Insect Resistance (IR) to detect GMOs. This method was developed for Roundup Ready soybean due to its specific characteristics. It is a non-invasive method and can be applied on-site, hence suitable for analysis of large sample lots of more expensive material, e.g. seeds.
There are three key issues of consideration during GM testing. Amongst these issues are Allergenicity, Toxicity and Compositional Analysis.
Candidate proteins expressed in GM crops are usually compared and contrasted with proteins that are allergenic or toxic using a weight of evidence approach consisting of individual and independent studies. Recognizing that most of the early generation GM crops were developed to express proteins, documents authored by (Codex alimentarius Commission (Codex), 2001, 2003a, 2003b, 2007; European Commission[EC], 1997, 2003a, 2003b, 2004; European Food Safety Authority EFSA, 2006a, 2006b; FAO, 1996; FAO/WHO, 2000; International Life Sciences Institute ILSI, 1996, 1997, 2003, 2004; OECD, 1993, 1997, 2003; WHO, 1995) highlighted that proteins are an integral component of the diet. It is however, acknowledged that there are some proteins that exist in nature that can present hazard in the form of potential for allergenicity or toxicity. A weight of evidence approach therefore has been developed based on what is known about allergenic and toxic proteins to compare candidate proteins with known allergenic and toxic proteins before commercialization.
The potential for allergenicity is assessed for proteins to ensure that they are not similar enough to cross react with the antibodies present in persons with food allergies. A key component in the allergenicity assessment is the source of proteins. This is one component of the safety assessment for individual proteins called History of Safe Use (HOSU; Constable et al.,2007). Another key component in the allergenicity assessment is a bioinformatics comparison of the amino acid sequence of the protein with the sequences of known allergenic proteins for similarity using computational methods. The identity and amino acid sequence of all known allergenic proteins is available online (www.allergenonline.org) and up-dated annually. A physical property shared by numerous, but not all, allergenic proteins is resistance to degradation in the presence of digestive enzymes (Astwood et al.,1996). In vitro methods have been developed to evaluate the sensitivity of proteins to degradation in the presence of digestive enzymes (pepsin and pancreatin). The primary basis of these considerations is that proteins selected from sources that are not known to produce toxic proteins, are not similar in sequence to known protein toxins, and are readily degraded in the presence of digestive enzymes that are unlikely to be toxins.
Proteins used in GM crops need to be assessed for potential to cause adverse effects. There are overlaps in the methods used to assess the potential toxicity and allergenicity of proteins, specifically, consideration of history of safe use of the source of the protein, bioinformatics comparison to known protein toxins, and in vitro resistance to digestive enzymes (Delaney et al., 2007). There exists a difference in the bioinformatics analysis compared with the allergenicity assessment. First, there are no pre-defined criteria that identify a “match” between two proteins. Second, there is currently no annotated and updated database in which the sequence of protein toxins is maintained. Rather, what is commonly conducted is a comparison to all known protein sequences in the NCBI BLAST database (http://blast.ncbi.nlm.nih.gov/Blast.cgi) followed by manual inspection to determine if sequence similarities are present.
An important component of the data produced in the comparative safety assessment is a detailed compositional analysis of the key nutrients, antinutrients, secondary metabolites and toxins of a GM crop and a non-GM comparator. GM crops can be analyzed chemically to determine their chemical composition. In the case of maize, soybeans, canola, rice and cotton, the concentrations of the components are available at a publicly available website that is managed by the International Life Sciences Institute(https://www.cropcomposition.org/query/index.html).
There are several categories of institutions with varying capacity for GMO testing. These can be classified as regulatory, service, research, teaching, and capacity building. Institutions with infrastructure, equipment and human resources capacity to conduct GMO testing in Nigeria are as contained in Annex 1.
Records of all GMO inactivation events must be presented to the NBMA for inspection. This record or GMO contained use notification should include the following:
Where waste is being autoclaved, biological indicators (or similar) must be used at least monthly in order to validate inactivation. Decontaminated waste should not be removed off‐site until such time as there is a positive inactivation result. A record of the validation must be maintained by the user.
This GM Testing protocol has highlighted important steps to be adopted during detection and necessary things to test for.
Table 1: Institutions with resources to carry out GMO testing in Nigeria
|NAME OF INSTITUTION||LOCATION||STATUS OF GMO TESTING||GMO TESTING EQUIPMENT AVAILABLE||GMO TESTING EXPERTISE||GMO TESTING ACCREDITATION||COLLABORATING INSTITUTIONS||CONTACT PERSON||CONTACT (EMAIL & PHONE|
|National Biotechnology Development Agency (NABDA)||NABDA, Umaru Musa Yar’adua Expressway Lugbe, Abuja||1. Have tested for LMO microorganisms and plasmid DNA from E. coli cells; mosquitoes (in the future)
2. Have tested for GMO plant
|Institute of Agricultural Research (IAR)||Ahmadu Bello University Zaria||Have tested for GMO plants (Bt Cowpea, and Africa Bio fortified Sorghum ABS)||Yes||Executive Director (Principal Investigators)|
|National Cereal Research Institute (NCRI||NCRI, Badeggi. Niger State||Have tested for GMO plants (NEWEST RICE||Yes||Executive Director (Principal Investigator)|
|National Root Crops Research Institute (NRCRI)||NRCRI Ikot Ekpene road Umudike, Umuahia, Abia State||Have tested for GM Cassava resistant to Cassava Mosaic Virus and Brown Streak Virus||Yes||Executive Director (Principal Investigators)|
|Federal University of Technology||FUTA Akure, Ondo State||Yes|
Table 2: List of crops that have been genetically modified, their events and unique modifiers and various protocols.
|CROP||EVENT/UNIQUE IDENTIFIER||EVENT DESCRIPTION||NUMBER OF PCR PROTOCOLS||PROTOCOL DESCRIPTION||NUMBER OF ELISA PROTOCOL||PROTOCOL DESCRIPTION||NUMBER OF STRIP-TEST PROTOCOL||PROTOCOL
|Cotton||MON 15895||Insect resistance|
|(i) Nitrogen use efficiency
(ii) Water efficiency
|Cassava||Stacked with Beta-Carotene trait||Vitamin A level increase|
|Cassava||AMY3 RNAi lines||Modified to obtain storage roots with lower post-harvest physiological degradation after harvest|
|Sorghum||ABS 321||Iron and zinc bioavailability|
|) is to reduce starch breakdown in storage roots of cassava after pruning the shoots, prior to harvest of the crop. The objective is|