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Fig. 2 | Malaria Journal

Fig. 2

From: Systematic identification of plausible pathways to potential harm via problem formulation for investigational releases of a population suppression gene drive to control the human malaria vector Anopheles gambiae in West Africa

Fig. 2

Spatial and temporal heterogeneity in genotypic dynamics and population suppression following simulated releases of dsxFCRISPRh transgenics. A previously reported model [19] was used to create plots showing typical dynamics of transgenic heterozygotes (dsxFCRISPRh/+) and homozygotes (dsxFCRISPRh/dsxFCRISPRh) at five sites (villages) that differ in their extent of seasonality and isolation from other human settlements. Hypothetical field protocol for problem formulation follows scenario modelled in simulated annual releases of 5000 transgenic heterozygous males over a 6-year period in 1% of human settlements (n = 434 of 42,260) in a 1 million sq. km grid in West Africa [19]. Representative simulations of genotypic and population dynamics are shown on a logarithmic scale for adult female population size at five site conditions: a Median seasonality and isolation: both seasonality and isolation from other human settlements in the 50th percentile; b Aseasonal and isolated: both aseasonality and isolation from other human settlements in the 95th percentile; c Seasonal and isolated: both seasonality and isolation from other human settlements in the 95th percentile; d Aseasonal and connected: both aseasonality and connectedness to other human settlements in the 95th percentile; e Seasonal and connected: both seasonality and connectedness to other human settlements in the 95th percentile. Solid lines in line graphs show numbers of adult female genotypes in populations where transgenic releases are occurring. Dotted lines represent simulations of numbers of wild type females in populations in the absence of population suppression gene drive. The low number (< 3%) [19] of non-functional cleavage resistant alleles [140] have been excluded here to provide visual clarity to the graphs. f Population suppression from gene drive intervention over calendar Year 5–6 compared to the year before transgenic releases. Means were obtained from ten simulations each of the different site conditions, controlled for rainfall, with error bars indicating minimum and maximum values observed

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