Target Malaria Ghana: Unlocking DNA and Ecosystem Knowledge
posté 25th mai 2020 par
Target Malaria started its work in Ghana in 2018, in partnership with the University of Ghana, Legon.
Different from other African countries where Target Malaria is present, Target Malaria Ghana does not have plans of working with modified mosquitoes. Instead, one of the main areas of research of our work is to understand what could happen if the population of Anopheles gambiae mosquitoes, the primary vector of malaria in sub-Saharan Africa, were to be substantially reduced or eliminated. This is part of the project’s commitment to responsible research: we need to ensure that if we were to release modified mosquitoes in the environment in the future, they would not harm the environment or our health.
The development of a local DNA barcode reference library of insects is part of Target Malaria Ghana’s activities. It will help answer a wide range of ecological questions that are not restricted to our project. Using samples collected from our studies sites, the research will shed light on the interactions among communities of arthropods and vertebrates, building a quantitative ecological network that enables the modelling of Anopheles gambiae’s impact on the ecosystem.
We are studying the ecological interactions of the communities around Anopheles gambiae’s larval and adult niches, including food webs and pollination interactions. We are using molecular metabarcoding of the faeces and stomach contents of insectivores, as well as larval mosquitoes, direct observation of pollination events, categorising insectivores around swarming sites and semi-natural experimental manipulations of larval breeding sites.
In simple terms, thanks to new molecular identification techniques, we can determine DNA barcodes that are specific to each species. Hence, we can identify the diversity and species composition of a community and, by analysing the content of their stomach or faeces, also determine predator diets and eating patterns.
We are using samples from areas surrounding villages in the Volta Region of Southern Ghana. We chose these sites because they offer a relatively well-defined and natural setting. Our criteria were distance to neighbouring communities, inhabitants’ receptiveness, levels of insecticide use, malaria endemicity, predominant mosquito species, breeding site availability, household density, population size, vegetation type, among others.
This work is carried out in partnership with colleagues from Target Malaria, the University of Ghana, the University of Oxford (UK) and the University of Guelph (Canada). It is of vital importance for our ecological studies. Because the impact of the initiative goes beyond our project, our library will be publicly available on the Barcode of Life Database (International Barcode of Life (iBOL) Consortium). The information we provide can be used in other locations to support efforts to discover, identify and protect species. We are contributing to the world’s capacity to understand and manage ecosystems, and to address biodiversity loss.
To learn how DNA barcode can speed up species discovery, and understand their interactions and dynamics; read about iBOL’s next research programme – BIOSCAN.