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Theme 4 re-opened: Experiences detecting transgenes in wild relatives [#3873]
As indicated last week, we are re-starting the discussion groups in the Network of Laboratories for LMO Detection & Identification. We are beginning by re-opening discussions on theme 4: experiences detecting transgenes in wild relatives. The description of the topic follows:

One of the suggested topics for discussion was for participants to share experiences and challenges with the detection of transgenes and/or their proteins in wild relatives. It was pointed out that this is a theme that the environmental authorities need to consider because it sometimes presents difficulties in detection. We encourage participants to post information on their experiences and any challenges with this issue. Some aspects to consider include:

* When to seek to detect whether transgenes have introgressed into wild relatives;
* Different approaches to detecting transgenes in wild relatives depending on the native biodiversity of an area (e.g. centre of origin, the presence of closely-related wild relatives to the living modified organism);
* How to conduct sampling in the field;
* How to adapt DNA- and protein-based tests commonly used for crops to wild relatives;
* How to report results.
posted on 2012-11-19 14:56 UTC by Ms. Kathryn Garforth, Secretariat of the Convention on Biological Diversity
RE: Theme 4 re-opened: Experiences detecting transgenes in wild relatives [#3876]
The detection of LMOs in wild relatives is going to be crucial in the future as GM research moves from high value commercial crops into such crops as sorghum, pearl millet, cowpeas and other minor crops of the world which are used as staples by indigenous peoples of Africa, Asia and South America, and with centres of diversity of such crops being found in the same environments.

As a country, we have very limited experience with the detection of LMOs in wild crop relatives as there is currrently very limited use of LMOs in the region. We have however laboratories that are undertaking LMO detection in field crops and we also had some studies on gene flow from cultivated to wild relatives of sorghum. Here we found out that there is very limited flow of genes from cultivated to sexually compatible populations of wild sorghums. This may be principally because sorghum is predominantly self pollinating. Thinings could have been different with crops like pearl millet which is predominantly out crossing.

We will therefore be following this discussion closely and would appreciate some lessons learnt from those who have been carrying out this form of research.

Abisai Mafa
National Biotechnology Authority of Zimbabwe
posted on 2012-11-20 13:53 UTC by Abisai Mafa
RE: Theme 4 re-opened: Experiences detecting transgenes in wild relatives [#3877]
Dear colleagues!
My name is Frank Narendja and I'm head of the GMO-detection laboratory at the Environment Agency Austria.
The questions and points for discussion posted by the SCBD with regard to the detection of transgenes are all very relevant but in my opinion not so easy to answer, because some of those depend very much on the national context. Let me try to explain:
The main question is what the requirements of your national legislation are, e.g. is there a general monitoring of introgression of transgenes foresessen, or is this only necessary if there is some kind of suspicion or an actual case? Do you need to have a quantitative result or is a yes/no answer, that means the proof of the presence of the transgene in a wild population enough to take action? The technical solutions very much depend on those basics.

Here are some thoughts on the points raised by the SCBD:
* When to detect? I guess there are several options. Just examples: As said above a general monitoring of introgression might be one reason. Another one might be to check the surrounding environment,  in case there has been an illegal planting.
* Different approaches: That's a very crucial point, as many technicalities (e.g. the sampling plan, the detection system chosen) depend on the local biodiversity. In my opinion this can only be answered on a case-by-case basis taking into account the species of LMO, the trait, and the local biodiversity.
* Sampling: Again this depends on the legal requirements, the biodiversity, and the resources (financial and human) available. The best would of course be to have a statistically valid sampling protocol, but that is costly and time consuming. Protocols are available and can be chosen from on a case-by-case basis.
* Adaptation of methods: For DNA methods the most crucial thing is most likely the availability of reference systems, as the reference gene used in the standard technique is usually species specific and will not work in wild relatives. More common genes can be used for qualitative testing, but not for quantitative analysis.
* Reports: that should be pretty straightforward as the expression of results and reporting should not be different from any other LMO analysis.

I hope that's some food for thought for the beginning. Looking forward to a fruitful discussion.
(edited on 2012-11-22 17:32 UTC by Frank Narendja)
posted on 2012-11-22 17:31 UTC by Dr. Frank Narendja, Environment Agency Austria (EAA)
RE: Theme 4 re-opened: Experiences detecting transgenes in wild relatives [#3902]
Dear Frank,

Thanks for posting your thoughts regarding different aspects of detecting transgenes in wild relatives. I wanted to follow-up with a few questions.

While I realize that LMOs have not been intentionally released into the environment in Austria, I am wondering whether there is nonetheless a policy in place regarding testing for the presence of transgenes in wild relatives. Do you conduct sampling in the field to test for the presence of transgenes that may have spread from other countries or been introduced into the environment unintentionally? If not, could you provide some information on why this has not been considered necessary? If yes, could you provide more details on how you conduct the sampling and detection?

Thank you,
Kathryn Garforth
posted on 2012-12-07 15:11 UTC by Ms. Kathryn Garforth, Secretariat of the Convention on Biological Diversity
Sampling in the field [#3878]
In April 2011, the CBD Secretariat organized a workshop for customs officials on the identification and documentation of LMOs which was kindly hosted by the Government of Slovenia at the Agricultural Institute of Slovenia.

One session of the workshop focused on sampling methods and Dr. Jelka Šuštar-Vozlič of the Agricultural Institute of Slovenia gave a presentation on this topic, which also included discussion of sampling in the field. The presentation is available in pdf format on the BCH: http://bch.cbd.int/forum/art18/customs%20officers/cee/sampling.pdf. The information on sampling in the field can be found on pages 42-51.

Best wishes,
posted on 2012-11-30 20:39 UTC by Ms. Kathryn Garforth, Secretariat of the Convention on Biological Diversity
RE: Sampling in the field [#3880]
Thanks for the ppt file for detecting. It is great to read. One point I want to share is that the distance of gene flow will be affected by the released area of crops. Small scale release may result in a certain rate of gene flow, but large scale release will increase the dispersal distance and the hybridization frequency.

Hybrids formed is the first step of gene flow, and the introgression of transgenes has to depend on many factors, such as the fitness of transgene in nature.


Wei Wei, Institute of Botany, Chinese Academy of Sciences
posted on 2012-12-01 01:41 UTC by Mr. Wei Wei, China
RE: Sampling in the field [#3883]
Posted on behalf of Gurinder Jit Randhawa:

Dear Kathryn,

You have rightly mentioned about Dr. Jelka Šuštar-Vozlič of the Agricultural Institute of Slovenia's presentation, infact during my visit to her institute in September 11 and while discussing with her about sampling strategies for GM detection, she shared with me her this presentation and which is also there on the link mentioned by you.

She has also published 2-3 good research papers also in this area, I am sending the copy of this mail to Jelka also, I am sure she would share her research publications with all of Us.

Kind Regards.

Dr. (Mrs.) Gurinder Jit Randhawa
Principal Scientist
National Research Centre on DNA Fingerprinting
National Bureau of Plant Genetic Resources
New Delhi-110012, INDIA
posted on 2012-12-03 19:52 UTC by Ms. Kathryn Garforth, Secretariat of the Convention on Biological Diversity
RE: Sampling in the field [#3884]
Posted on behalf of Jelka Šuštar Vozlič

Dear Colleagues,

In addition to the information provided in the presentation please find bellow link to the articles that we have published on the topic ‘Sampling in the field’:

Šuštar-Vozlič J., Rostohar K., Blejec A., Kozjak P., Čergan Z., Meglič V.. 2010. Development of sampling approaches for the determination of the presence of genetically modified organisms at the field level. Anal. bioanal. chem., 396,6: 2031-2041,
Available at: http://link.springer.com/article/10.1007%2Fs00216-009-3406-4

Onori R., Šuštar Vozlič J., Bellochi G. et al. 2012: GMO Sampling Strategies in Food and Feed Chains. In: Bertheau Y (Ed.): Genetically Modified and non-Genetically Modified Food Supply Chains. Co-Existence and Traceability. Wiley Blackwell, p.243-272.
Hardcopy http://eu.wiley.com/WileyCDA/WileyTitle/productCd-1444337785.html
Ebook http://onlinelibrary.wiley.com/book/10.1002/9781118373781

Best regards,

posted on 2012-12-03 19:53 UTC by Ms. Kathryn Garforth, Secretariat of the Convention on Biological Diversity
RE: Theme 4 re-opened: Experiences detecting transgenes in wild relatives [#3879]
Dear Colleagues,

I am Wei Wei from China and currently working on the gene flow from genetically modified oilseed rape to its wild relative weedy brown mustard in China and its ecological consequences. I appreciate this opportunity of discussion detecting transgenes in wild relatives.

Gene flow from crops to their wild relatives is a classic topic of research. Crop wild relatives are important resources for further crop improvement to cope with global climate change and to assure food safety. The introduced of transgene raises the concern on the introgression of the foreign transgenes in the wild and if the integrated transgenes could increase the frequency of gene flow from crops to the wild relatives.

It has been reported that the herbicide resistant transgene was found in the wild Brassica rapa in Canada, thus the spontanoues introgression of transgenes really happens in nature. Sampling strategy is therefore crucial for the detection of transgene in wild relative. Regarding of this issue we should firstly indentify the area where gene flow is likely to happen or the risk is relatively high. Then the sampling can be further developed according to the local condition and local distribution. The sampling should also take into consideration of the characteristics of the wild populations as well as that of the transgenic traits.

posted on 2012-12-01 01:15 UTC by Mr. Wei Wei, China
RE: Theme 4 re-opened: Experiences detecting transgenes in wild relatives [#3954]
Dear participants,

I have also recently come across an article, which may be of relevance to this topic - "Detection of airborne genetically modified maize pollen by real-time PCR" by Silvia Folloni et al. that was published in the September 2012 issue of Molecular Ecology Resources, http://onlinelibrary.wiley.com/doi/10.1111/j.1755-0998.2012.03168.x/abstract.

I have pasted the abstract below. The full text is behind a pay-wall but I have also managed to obtain a copy via a colleague so please contact me if you would like the full text.

I would be most interested in the thoughts and comments of others on the article and how it might relate to detecting transgenes in wild relatives.

Best wishes,

Detection of airborne genetically modified maize pollen by real-time PCR

The cultivation of genetically modified (GM) crops has raised numerous concerns in the European Union and other parts of the world about their environmental and economic impact. Especially outcrossing of genetically modified organisms (GMO) was from the beginning a critical issue as airborne pollen has been considered an important way of GMO dispersal. Here, we investigate the use of airborne pollen sampling combined with microscopic analysis and molecular PCR analysis as an approach to monitor GM maize cultivations in a specific area. Field trial experiments in the European Union and South America demonstrated the applicability of the approach under different climate conditions, in rural and semi-urban environment, even at very low levels of airborne pollen. The study documents in detail the sampling of GM pollen, sample DNA extraction and real-time PCR analysis. Our results suggest that this ‘GM pollen monitoring by bioaerosol sampling and PCR screening’ approach might represent an useful aid in the surveillance of GM-free areas, centres of origin and natural reserves.
posted on 2012-12-13 15:20 UTC by Ms. Kathryn Garforth, Secretariat of the Convention on Biological Diversity
RE: Theme 4 re-opened: Experiences detecting transgenes in wild relatives [#3965]
Dear Kathryn, Dear Colleagues:

First, I wish to express on behalf of my national colleagues our appreciation for maintaining the BCH Laboratory Network forum; we find this is a useful and powerful platform to get technical experts up to date with nice ideas and practical advice. Personally, I am delighted to have the opportunity to follow closely the posted opinions and share experiences on transgene detection as I am involved with the biosafety networks for monitoring, detection, identification and quantification of GMO, coordinated by our National Biosafety Commission (CIBIOGEM) in Mexico. For our Country, it is of utmost importance to define the best criteria for proactively detect GM presence in wild relatives. In our national context, where the biodiversity richness is regarded as a strong asset, we have also the responsibility of maintaing certitude on detection results as a Center of Origin and Diversity of some of the main crops such as maize. Therefore, solid strategies that allow for obtaining accurate results, practical implementation and facility of use are sought constantly by our local authorities as well as our public research institutions in support of the national biosafety regulation and public concerns.

As many of you might know, the detection of transgenes in local maize landraces has been a controversial issue for some time now in our region (Please refer to Quist & Chapela 2001, Ortiz-García et al 2005, Cleveland et al 2005, Mercer & Winwright 2008, Dyer et al 2009, Piñeyro-Nelson et al 2009, Schoel & Fagan 2009, Van Heerwaarden et al 2012). A recent report indicates that transgenic material was also found in cotton wild relatives (Wegier et al 2011), giving rise to many speculations as to whether or not the persistence of those sequences might have a significant effect, indicate introgression or pose some meaningful risks that ought to be addressed, not to mention the task to evaluate the effect on other sexually compatible species that are also present. The value of such reports opens big challenges for finding useful detection strategies for large scale analyses and also for being able to compare and make good interpretation of the results given the extension and different geographic regions within the Country. Polemics often derives from publications such as the examples, but I hope their relevance might be clarified from a more technical perspective by evaluating the type of methods used, sampling strategies or accuracies in frequency level calculations that if I might say depends on my opinion on the statistical approaches taken, so I’d love to hear more objective opinions from this group (maintaining the discussion on the technical side) in order to come up with productive ideas to follow after the possible use of current available methods and novel statistics tools that might become suitable for the task.

Sharing our experiences to date, I must mention that our local regulation instructs for having mechanisms in place for monitoring and assessing the potential risks that GMOs might pose considering environment, health and biodiversity. In this regard, National Competent Authorities’ make every effort to perform inspection and monitoring activities based on established protocols, following strategic monitoring plans according to their competences. These plans are used systematically for verifying compliance of GMO users with the biosafety conditions either by post-release monitoring, or else by detecting accidental or unintended GMO release. Once collected, samples are sent to specialized laboratories for validating analyses. Some detail can be found in the next links (please notice the information is in Spanish):
http://www.senasica.gob.mx/?id=2416; http://www.profepa.gob.mx/innovaportal/v/251/1/mx/organismos_geneticamente_modificados.html;

Their sampling strategies have been adapted to local needs and normal testing includes field level sampling (presumptive Strip-test at field sites complemented by laboratory confirmation of larger collects) applying simple-random sampling, they take in consideration several aspects: plant development stages at the time of collection, crop-field lay-out, uniformity of the field, and the purpose of the monitoring activity. In general leaves, cobs and kernels are collected according to ISTA’s protocols. When necessary, sub-sampling follows in the lab as is indicated by GIPSA statistical procedures, so samples can suffice aiming for LOD’s around 0.01%. Optimal sample size is sometimes a bottle-neck when trying to establish presence in the field, because in order to have proper representation of native/wild varieties collected from local communities the amount of starting material can be limited.

On the other hand, new approaches are frequently explored. The National Institute of Ecology and Climate Change, as part of the Ministry of Environment together with aerobiology experts at UNAM have some experience on sampling and detecting airborne GM maize pollen, taking advantage of the availability of authorized field release (at experimental scale) at the northern states performed between 2010 and 2011 (CENICA, unpublished data). Therefore, Folloni et al's recent reference is a detection approach we will for sure look at in detail and hope we’ll come back with comments some soon after. 

Federal efforts are complemented with two Biosafety research networks we've recently installed: The Mexican GMO Monitoring Network (http://www.cibiogem.gob.mx/RedMexOGMs) and the National Laboratory Network for the Detection, Identification and Quantification of GMOs. The two of them are currently involved with the standardization of protocols and methods for monitoring GMO presence and effects in the field. One of the issues not so simple  to adress has been prioritizing GMO monitoring activities at large scale in order to obtain sufficient representation of the collect so it results can be extrapolated and compared from zone to zone, so your advice and experiences on this topic are very welcome and relevant for us. Also, regarding the report of the results since the field monitoring has strong connection to laboratory procedures, we find that a crucial step is to be clear as to how sampling was taken so analysts can extrapolate outcomes to meaningful conclusions. The collection has to involve close communication between the field and lab teams and requires clarity on both sides as to the objectives of the monitoring.

Currently there are around 101 authorized GM events in Mexico (47 maize, 26 cotton), so another challenge we are facing is to have proper tools for field detection for most if not all of them as well as for other unknown events currently unauthorized.

Addressing earlier comments on this forum, as Dr Nrendja correctly points out, a hard task is to establish suitable biosafety action plans on the regions where wild relatives thrive. I agree this will be better answered on a case-by-case basis, so forgive me if I continue to use maize as an example. I also acknowledge Dr Wei Wei’s post on gene flow distance implications; nonetheless, we might also wish to consider the human factor as immigrant populations can signify a challenge where some agricultural practices may disperse GM material to the regions where wild relatives exist.

Inside our context, it has been very difficult to decide how best monitor the possibility of GM introgression to wild relatives when no defined baselines are available; efforts for having reference systems and indicators can be put in place from ongoing research (hopefully these will help establish validated methods for better addressing current limitations). Just as an example, distribution of local landraces has been under scrutiny in Mexico setting more specific protection goals, and some serious studies on morphological and molecular characterization starts to come to light from Research centers and Institutes. Laboratory research has been carried out in parallel to evaluate GM presence these samples sets and are currently under revision. In summary, National collections were screened for the presence of GM content, and here lab results can serve different purposes: in the case of Germplasm banks a yes/no answer could be an useful result for curing the collection, but for in situ conservation (on the field maintainance of local diversity), if the goal is to evaluate how well is preserved the purity of local varieties or wild relatives, quantitating becomes a real issue. The frequency is key to indicate the extent of GM release or prevalence, and most of the time the results might come up negative depending on the sampling strategy and extension. For the case where intentional sowing is identified, positive samples are evident, but in other cases where samples appear to be weak positives, detection with quantitative methods might indicate presence at very low levels so it becomes sometimes difficult to ascertain correctly GM presence. I wonder if any of the forum expert has come around this challenge and possible solutions.

To finish, I’d like to thank all earlier comments and the useful links and references provided we’ll be attentive of extra information you’d like to share, and look forward to maintain an active collaboration with all experts since we have high expectations about outcomes of this discussion group. Congratulations again and await your comments.

Thankyou and best regards,

Natalhie Campos-Reales,
Deputy-Director of Science and Technology Development and Innovation
Executive Secretariat CIBIOGEM

P.S. Coextra’s book seems a good compendium of several topics we are interested in, I could only have access to the index, is it already available for request? Thanks.
posted on 2012-12-14 03:54 UTC by Dr. Natalhie Campos-Reales, National Commission on Biosafety and GMOs (CIBIOGEM)
RE: Theme 4 re-opened: Experiences detecting transgenes in wild relatives [#3978]
Many thanks for the shared information. They are very interesting. As most scientists might agree, the detection of highly risky sites of gene flow would be a cruicial step in detecting transgenes in wild relatives. Among many factors that affect the gene flow from transgenic crop to its wild relatives, the co-occurance of both the transgenic crop and wild relatives would be essential. It has been a chanllenge to detect transgene in wild relatives if we do not know where the transgenic crops are distributed, thus the first step of detecting transgene in wild would be to descrinimate transgenic crops themselves.
In China, where is the original center of wild soybean that frequently distribute along soybean field, scientist had reported potential gene flow happened between wild soybean and the cultivated soybean. Those area where gene flow is likely to occur will be the targeted sites to detect gene flow.
Though the gene flow among Brassica species is quite easy to happy, I did not yet find any evidence of spontaneous introgression of crop gene in the wild relatives of Brassica in China. We dont yet have commercialized plantation of transgenic Brassica in China. Dr. Warwick published a report in Molecular Ecology in 2008 on the finding of herbicide resistant transgene in wild B. rapa in Canada where transgenic canola had been grown for years. That is confirmed by the persistence of herbicide resistant gene and the most interesting thing is that the wild B. rapa carring transgene has similar genome size to the wild plant other than a type intermidiated between crop and wild. The authors suggested that the gene flow and introgression could have happened for several generations and the transgene has been fixed in wild.
posted on 2012-12-14 16:19 UTC by Mr. Wei Wei, China
RE: Theme 4 re-opened: Experiences detecting transgenes in wild relatives [#3977]
Dear participants,

We wished to inform you that we will keep the discussions on the current theme open for another week, i.e. until December 21st. We will then close the discussions over the holidays and resume with a new topic in the new year.

The Secretariat will also be sending messages to remind people of the Lab Network and to encourage additional participants to join.

So please continue to share information on experiences detecting transgenes in wild relatives as well as sharing the word with others who may be interested in taking part!

Best wishes,
posted on 2012-12-14 16:12 UTC by Ms. Kathryn Garforth, Secretariat of the Convention on Biological Diversity
RE: Theme 4 re-opened: Experiences detecting transgenes in wild relatives [#3995]
Dear Collegues,

First, I want to thank the Secretariat for hosting this forum and Katheryn for moderating, in order to exchange experiences and ideas on this interesting subject of LMO detecion in wild relatives. I just “got wind” of this forum the other day, and wanted to offer some points for discussion even here on this final dayn of discussion.

Of note, based on the conversation so far, it seems that domesticated “local” varieties are included in this definition of wild relatives - which is ok by me  - as an important sources of genetic diversity and hence biological diversity. Its probably useful to be clear that we are talking about a more expansive definition, as the dicussion might otherwise be limited to wild relatives that are centers of origin and not centers of diversification. For example, the genetic diversity of maize landraces in Bolivia is of the order of that known from Mexico, and comprise an important source of genetic diversity of this important crop plant.

With this clarification in mind, I wanted to share some perspectives and experiences on a number of issues related to the challenges of detecting LMOs or their products in wild relatives /landraces, as “food for thought” on practical matters of testing, and give a few reflections from the very interesting discussion that has so far taken place.

1.  Subjectivity in sampling and testing

While the discussion here is indeed in part of a technical nature (and yes, there are many technical challenges) keep in mind that the most momentous issues are not technical or even “objective” in nature, the subjective elements of LMO detection. Getting these right are essential if the testing is going to be robust, cost-effective, and efficient in meeting the stated objectives.

Here I am talking about choices such as sampling / sample pooling sizes, LOD designations, cutoffs for end-point (presence /absence) determinations, sizes of acceptable type I and type II errors, p-values from statistical inference. The question becomes what is “best practice” is thus largely subjective and often political, and ultimately dependent on broader values of how conservative one wishes to be in their analysis. Dr. Campos-Reales already gave a few references to papers that give good discussions and illustratons on this aspect from two viewpoints.

My own viewpoint is that these subjective choices should be guided by the most scientifically robust and defensible analysis possible, meanwhile recognizing uncertainties in the strength of evidence. This must also take into account limitations in sampling (where one can always sample more/broader to have a more robust result), however being conservative about the strength of evidence and the veracity of any scientific claim (such as a LMO detection result) often go hand and hand.

2. Detection limitations

a. The senstivity of ones detection system is dependent on the LEAST sensitive step, not the most. Thus, it does not matter if your practiacal LOD is 0.05 or even lower if your field sampling would be insufficient with reasonable certainty detect the LMO if it was indeed present.

b. Protocols for LMO detection are often optimized for specific species or varieties, use for wild varieties may require optimization and further verification through proper controls. For example, in PCR-based testing, the specific biochemistry of the wild relatives may not be optimial for PCR, where inhibitory compounds may influnece PCR amplification. Inhibiition reactions and controls become necessary. Not an insurmountable challenge, but must be kept im mind and accounted for.

c. Gene silencing may occur after introgression (hybridization) rendering certain types of testing (unfortunately also the cheapest/field ready/least complicated/ most user friendly), such s protein-based detection, insufficient for detecting LMOs. DNA-based methods can help, but may face similar challenges if transgene inactivation is occuring at the genomic level.

The larger message from a – c above is that a definitive “negative” result may be more challenging to ascertain than may seem the case. It is of course more difficult to prove a negative result. Here again, subjective decisions weigh heavily. Policies that favor protection, and hence are more likely to overestimate rather than underestimate the presence of LMOs in wild relatives, such as those in line with the objectives of the Protocol, should be strongly considered.

3. Monitoring

Dr. Campos-Reales in her thoughtful and useful contribution discusses what she sees as a challenge for monitoring LMOs in wild relatives, particularly for a country like Mexico, where “ it has been very difficult to decide how best monitor the possibility of GM introgression to wild relatives when no defined baselines are available”. I must admit I was a bit confused by this comment. It seems to me quite clear, in this case the “possibility of GM introgression” is characterized by the the selected wild relatives/landraces as indicators and the occurance of LMO material/products as your parameter to measure. The baseline is simply the “time zero” before LMO release into that environment.

Keep in mind, that monitoring often does not measure effects, but changes  - then those changes  can be investigated whether they can be linked to a certain adverse an adverse effect (e.g. decrease in genetic diversity, fitness, etc) , via a general or specific hypothesis. This is what I think Dr. Campos-Reales may have been referring to, what indicator or parameter to select to observe adverse effects. The first step is to detect changes.

The challenge facing Mexico, in the example of maize provided, seems two-fold and linked to dthe regulatory decisions taking place.

First, baselines of the “time zero” become more difficult as Mexico increases its scale of release of approvals of LM maize. Second, Mexico, if I understand correctly,  does not currently make regulatory use of “General Surveillence” as a montioring activity option. This  kind of monitoring that is often employed to look for changes for which a particular risk scenario had not been identified through the course of a risk appraisal. Putting baseline studies in place and making use of General Surveillance practices hence might be a sensible approach if conservation of maize genetic diversity in the face of uncertainty is a priority.

4. Useful publications:

A few publications that others may find useful on this subject, particularly related to sampling, potential adverse effects, real-example detection challenges and background information are included in this posting.

I look forward to the rest of the discussion on this interesting topic!

Kind regards,

David Quist
posted on 2012-12-21 10:28 UTC by David Quist
RE: Theme 4 re-opened: Experiences detecting transgenes in wild relatives [#3996]
Dear colleagues,

Thank you very much for your contributions to this forum over the past few weeks. I believe we have had a very enriching discussion.

The forum is now closed. We will resume discussions in the new year.

All the best for the holiday season,
posted on 2012-12-21 21:14 UTC by Ms. Kathryn Garforth, Secretariat of the Convention on Biological Diversity