[ Contents ] [ APJMBB home ]

As. Pac. J. Mol. Biol. & Biotech., June 2010 Vol. 18, 2

Letter from the Guest Editor.

Modified insects: Risk analysis and public engagement

     The first special issue on transgenic insects (Volume 17, Number 3) featured two mini-reviews – Wilke et al. (2009) summarised the potential benefits of transgenesis in enabling the Sterile Insect Technique (SIT) against selected mosquito vectors, while Brelsfoard & Dobson (2009) discussed strategies to suppress or modify insect pests and disease vectors through the use of naturally occurring and genetically modified Wolbachia strains. In this special issue (Volume 18, Number 2), Morrison et al. (2010) review genetic improvements to the SIT for agricultural pests – covering both classical genetics and transgenesis. They discuss strains created through classical genetics in Dipterans (e.g. Australian Sheep Blowfly Lucilia cuprina, Mediterranean fruitfly Ceratitis capitata) and Lepidopterans (e.g. silkworm Bombyx mori, Mediterranean flour moth Ephestia kuehniella), and outline possibilities for improving the SIT through transgenesis, focusing on advances such as genetic marking, radiation replacement, transgenic sexing, and combination of these features. However, their review does not discuss oft-quoted success stories such as eradication of the New World Screwworm (Cochliomyia hominivorax) from North and Central America (Dyck et al., 2005) because SIT has been deployed against these insect pests without the need for genetic improvements thus far. Morrison et al. (2009) correctly mention regulatory acceptance and uncertainty over public perception of genetic modification as key challenges to overcome before the technology could be successfully deployed to benefit mankind, reiterating similar observations by other authors on the importance of community engagement in research with modified mosquitoes (Curtis & Reuben, 2007; Vasan, 2009; El Zahabi-Bekdash & Lavery, 2010). Thus, in addition to scientific considerations and general issues that should be addressed in most trials involving mosquitoes (McKemey et al., 2008), there are also important ethical, social and cultural considerations for site selection (Lavery et al., 2008). This is of topical importance: Cayman Islands (British Overseas Territory) has been conducting open field trials since 2009 (Wilson, 2009) with genetically modified male Aedes aegypti mosquitoes described by Phuc et al. (2007), while Malaysia is expected to follow suit in 2010 (TropIKA, 2010). It has been reported that Australia is likely to conduct open releases of modified female Aedes aegypti infected with Wolbachia in January 2011, with subsequent open releases planned in Thailand and Vietnam (Moreira et al., 2009; Jeffrey et al., 2009; Murphy et al., 2010; Eliminate Dengue Project first e-newsletter, May 2010). As Marshall et al. (2010a) have stated, social science is increasingly relevant as the technology moves from laboratory to field. These authors recently conducted a qualitative survey of attitudes to transgenic mosquitoes for malaria control in Mali (Marshall et al., 2010b), and have built upon that work to produce a series of closed questions that could be easily adapted to measure public attitudes in other countries towards the deployment of genetically modified vectors (Marshall et al., 2010a). More such studies are needed to enable better communication of benefits and risks to the public, especially as risk assessments are now available for open releases involving the aforesaid modified and genetically modified Aedes aegypti strains (Beech et al., 2009; Murphy et al., 2010). Beech et al. (2009) reported 31 risks of a hypothetical open field release of a self-limiting transgenic Aedes aegypti mosquito strain to combat dengue. Patil et al. (2010) have provided a useful critique of that exercise, adding two risks to the 31 identified for a bi-sex lethal strain (such as the one described in Phuc et al., 2007), and identifying eight more risks for another strain in which the penetrance is female-specific flightlessness (Fu et al., 2010). Risk assessment is seldom complete or exhaustive, and should never be a static or one-off exercise; regular re-assessment is important to ensure that it is a living document, and as comprehensive and up-to-date as possible. Patil et al. (2010) is a step in that direction for self-limiting strains, while we may expect similar refinements in the near future for self-propagating strains (e.g. Moreira et al., 2009). For instance, the 50 risks identified by Murphy et al. (2010) can be improved by considering the risk of the strain spreading beyond the proposed release sites (as single infection of one individual may lead to global conversion of an entire species – something that has probably happened thousands of times), and by making clearer distinctions between different Wolbachia strains under consideration, between different phenotypes they induce in different insects, and between limited-time trial versus limited-time release intending to result in a permanent establishment. A lot can also be learnt by comparison of risk assessments such as Beech et al. (2009), Patil et al. (2010), and Murphy et al. (2010); after all, they pertain to cognate and complementary technologies with the common objective of reducing disease burden.



S.S. Vasan, DPhil (Oxon)
Guest Editor
Asia Pacific Journal for Molecular Biology and Biotechnology

 

REFERENCES

Beech, C. J., Nagaraju, J., Vasan, S. S., Rose, R. I., Othman, R. Y., Pillai, V. and Saraswathy, T. S. (on behalf of the working groups) 2009. Risk analysis of a hypothetical open field release of a self-limiting transgenic Aedes aegypti mosquito strain to combat dengue. Asia Pacific Journal of Molecular Biology and Biotechnology 17(3): 99-111.

Brelsfoard, C. L. and Dobson, S. L. 2009. Wolbachia-based strategies to control insect pests and disease vectors. Asia Pacific Journal of Molecular Biology and Biotechnology 17(3): 55-63.

Curtis, C. F. and Reuben, R. 2007. Destruction in the 1970s of a research unit in India on genetic control of mosquitoes and a warning for the future management of transgenic research. Antenna 31: 214-216.

Dyck, V. A., Hendrichs, J. and Robinson, A. S. (eds.). 2005. Sterile insect technique: Principles and practice in area-wide integrated pest management. The Netherlands: Springer. Eliminate Dengue Project first e-newsletter. May 2010. Available online at: http://www.eliminatedengue.com/Portals/58/enews/eNews1_ 2010.htm.

El Zahabi-Bekdash, L. and Lavery, J. V. 2010. Achieving precaution through effective community engagement in research with genetically modified mosquitoes. Asia Pacific Journal of Molecular Biology and Biotechnology 18(2): 247-250.

Fu, G., Lees, R. S., Nimmo, D., Aw, D., Jin, L., Gray, P., Berendonk, T. U., White-Cooper, H., Scaife, S., Phuc, H. K., Mati¬notti, O., Jasinskiene, N., James, A. A. and Alphey, L. 2010. Female-specific flightless phenotype for mosquito control. Proceedings of National Academy of Sciences of the United States of America 10: 1073.

Jeffrey, J. A. L., Thi Yen, N., Nam, V. S., Nghia, L. T., Hoffmann, A. A., Kay, B. H. and Ryan, P. A. 2009. Characterizing the Aedes aegypti population in a Vietnamese village in preparation for a Wolbachia-based mosquito control strategy to eliminate dengue. PLoS Neglected Tropical Diseases 3(11): e552. Available online at: http://www.plosntds.org/article/info%3Adoi%2F10.1371%2Fjournal.pntd.0000552.

Lavery, J. V., Harrington, L. C. and Scott, T. W. 2008. Ethical, social, and cultural considerations for site selection for research with genetically modified mosquitoes. American Journal of Tropical Medicine and Hygiene 79: 312-318.

Marshall, J. M., Toure, M. B., Traore, M. M. and Taylor, C. E. 2010a. Towards a quantitative assessment of public attitudes to transgenic mosquitoes: Questions based on a qualitative survey in Mali. Asia Pacific Journal of Molecular Biology and Biotechnology 18(2): 251-273.

Marshall, J. M., Toure, M. B., Traore, M. M., Famenini, S. and Taylor, C. E. 2010b. Perspectives of people in Mali, West Africa toward genetically modified mosquitoes for malaria control. Malaria Journal 9: 128. Available online at: http://www.malariajournal.com/content/9/1/128.

McKemey, A. R., Beech, C. and Vasan, S. S. 2008. Principles of field studies on Aedes mosquitoes. In: Vasan, S.S. & Lee, H.L. (eds.) Proceedings of the 2nd intensive workshop on wild type and genetically sterile Aedes mosquitoes, 1-8 July 2008. Kuala Lumpur, Malaysia: WHO Collaborating Centre for Ecology, Taxonomy and Control of Vectors of Malaria, Filariasis and Dengue.

Moreira, L. A., Iturbe-Ormaetxe, I., Jeffrey, J. A., Lu, G., Pyke, A. T., Hedges, L. M., Rocha, B. C., Hall-Mendelin, S., Day, A., Reigler, M., Hugo, L. E., Johnson, K. N., Kay, B. H., McGraw, E. A., van den Hurk, A. F., Ryan, P. A. and O’Neill, S. L. 2009. A Wolbachia symbiont in Aedes aegypti limits infection with dengue, chikungunya, and Plasmodium. Cell 139: 1268-1278. Available online at: http://www.eliminatedengue.com/Portals/58/moreira%20et%20al%202009.pdf. Morrison, N. I., Koukidou, M., Franz, G., Miller, T. A., Saccone, G., Simmons, G. S., Alphey, L. S., Polito, L. C. and Naga¬raju, J. 2010. Review: Genetic improvements to the Sterile Insect Technique for agricultural pests. Asia Pacific Journal of Molecular Biology and Biotechnology 18(2): 275-295.

Murphy, B., Jansen, C., Murray, J. and De Barro, P. 2010. Risk Analysis on the Australian release of Aedes aegypti (L.) (Diptera: Culicidae) containing Wolbachia. Australia: CSIRO. Available online at: http://www.eliminatedengue.com/Portals/58/PDFs/NEW-Risk%20Analysis%20of%20proposed%20Wolbachia%20Aedes%20aegypti%20release%20Final%20Report%20for%20public%20release%209%20March%202010.pdf

Patil, P. B., Alam, M. S., Khan, S. A., Ghimire, P., Lacroix, R., Kusumawathie, P. H. D., Chowdhury, R., Sunish, I. P., Xu, L., Phong, T. V., Moe, M. A., Burneebaatar, B., Thanispong, K. and Dharamsingh, D. V. 2010. Letter to the Editor: Discussion on the proposed hypothetical risks in relation to open field release of a self-limiting transgenic Aedes aegypti mosquito strains to combat dengue. Asia Pacific Journal of Molecular Biology and Bio¬technology 18(2): 241-246.

Phuc, H. K., Andreasen, M. H., Burton, R. S., Vass, C., Epton, M. J., Pape, G., Fu, G., Condon, K. C., Scaife, S., Donnelly, C. A., Coleman, P. G., White-Cooper, H. and Alphey, L. 2007. Late-acting dominant lethal genetic systems and mosquito control. BMC Biology 5: 11. TropIKA (Tropical Diseases Research to Foster Innovation and Knowledge Application). 2010. Dengue: new so¬lutions are in sight. TopIKA.net (available online at: http://www.tropika.net/svc/news/20100330/Chinnock-20100330-News-dengue-GMetc-ed%5B1%5D).

Vasan, S. S. 2009. Transgenic insects: From laboratory to field (Letter from the Guest Editor). Asia-Pacific Journal of Molecular Biology and Biotechnology 17(3): 53-54.

Wilke, A. B. B., Nimmo, D. D., St John, O., Kojin, B. B., Capurro, M. L. and Marrelli, M. T. 2009. Mini-review: Genetic enhancements to the sterile insect technique to control mosquito populations. Asia Pacific Journal of Molecular Biology and Biotechnology 17(3): 65-74.

Wilson, S. 2009. MRCU looks to modify mozzies. CayCompass.com (2 October 2009) (available online at: http://www.compasscayman.com/caycompass/2009/10/01/MRCU-looks-to-modify-mozzies/).



[Get pdf]