John M. Marshall's research while affiliated with University of California, Berkeley and other places

Publications (17)

Article
Full-text available
Recent advances in gene editing technologies have opened new avenues for genetic pest control strategies, in particular around the use of gene drives to suppress or modify pest populations. Significant uncertainty, however, surrounds the applicability of these strategies to novel target species, their efficacy in natural populations, and their even...
Preprint
Full-text available
Background: Attractive targeted sugar baits (ATSBs) are a promising new tool for malaria control as they can target outdoor-feeding mosquito populations, in contrast to current vector control tools which predominantly target indoor-feeding mosquitoes. Methods: We sought to estimate the potential impact of these new tools on Plasmodium falciparum ma...
Article
Full-text available
Background In the summer of 2013, Aedes aegypti Linnaeus was first detected in three cities in central California (Clovis, Madera and Menlo Park). It has now been detected in multiple locations in central and southern CA as far south as San Diego and Imperial Counties. A number of published reports suggest that CA populations have been established...
Article
Full-text available
Progress towards controlling and eliminating parasitic worms, including schistosomiasis, onchocerciasis, and lymphatic filariasis, is advancing rapidly as national governments, multinational NGOs, and pharmaceutical companies launch collaborative chemotherapeutic control campaigns. Critical questions remain regarding the potential for achieving eli...
Data
Supporting information text file containing mathematical details of the compartmental model used in the main text and the derivation of the effective reproduction number. (PDF)
Article
Replacement of wild insect populations with transgene-bearing individuals unable to transmit disease or survive under specific environmental conditions using gene drive provides a self-perpetuating method of disease prevention. Mechanisms that require the gene drive element and linked cargo to exceed a high threshold frequency in order for spread t...
Article
Full-text available
Versatile molecular tools for creating driving transgenes and other invasive genetic factors present regulatory, ethical, and environmental challenges that should be addressed to ensure their safe use. In this article, we discuss driving transgenes and invasive genetic factors that can potentially spread after their introduction into a small propor...
Article
Full-text available
Approximately two years ago, two of us (E.B. and V.G.) demonstrated the first experimental application of CRISPR–Cas9 to 'drive' a desired trait throughout a population of fruit flies. In November 2015, this same team at the University of California, San Diego, joined with A.A.J. and others at the University of California, Irvine, to develop a CRIS...
Article
Full-text available
Insecticide-treated nets and indoor residual spray programs for malaria control are entirely dependent on pyrethroid insecticides. The ubiquitous exposure of Anopheles mosquitoes to this chemistry has selected for resistance in a number of populations. This threatens the sustainability of our most effective interventions but no operationally practi...
Article
Mosquito population replacement requires gene drive mechanisms in order to spread linked genes, mediating disease refractoriness, through wild populations. Medea is predicted to be a low threshold gene drive mechanism, able to spread from low initial frequency.
Article
Novel vector control strategies are of great interest because currently-available tools are not expected to eliminate malaria from highly-endemic areas. Current vector control strategies focus on indoor measures, such as insecticide-treated nets, however this is selecting for mosquitoes that tend to bite outdoors.

Citations

... With the recent expansion of genomic resources and analytical approaches to detect polygenic adaptation (Pritchard & Di Rienzo, 2010), quantitative genetics and an appreciation for the impact of genetic redundancy can provide new insights into evolutionary conundrums that are difficult to explain in classical population genetics, such as repeated evolution in insecticide resistance (Pélissié et al., 2022), and the phenomenon of host switching in herbivorous insects. Future work could also focus on different hierarchical levels of redundancy in insecticide resistance and other traits of interest, including gene redundancy, functional redundancy, regulatory network redundancy (Fagny & Austerlitz, 2021) and redundancy underlying well-known general mechanisms (Feyereisen et al., 2015), thereby improving understanding of adaptive evolution and gene-based strategies (Legros et al., 2021) for pest control. ...
... Pless et al. (2017) reported that Southern California populations of Ae. aegypti are distinct from Northern California populations and came from southwest U.S. and northern Mexico. Similarly, Lee et al. (2019) reported that recent introductions of Ae. aegypti into California are from multiple, genetically diverged source populations. More specifically, Pless et al. (2017) found that the Southern California lineage diverged from the Southwest/Mexico lineage approximately 22 years ago. ...
... High-transmission settings with a high adult burden of infection might not achieve the EPHP goal, regardless of the postponement. 24,26 For these settings, an increase in SAC coverage and inclusion of adults is necessary to achieve EPHP by 2030. We acknowledge that due to limited praziquantel supplies (donations), 27 including adults in treatment may not be feasible in all areas. ...
... Various types of toxin-antidote drives have also been modeled [18][19][20][21][22][23][24]. Some of these have been proven to be capable of spreading in Drosophila experiments [25][26][27][28][29][30][31]. However, more research is needed to find suitable promoters and target sites and to successfully construct these new types of drives with desired properties in target species. ...
... Frequently, cell lines and mosquito colonies are exchanged between researchers without validation, verification or colony standardization. As gene drives and CRISPR-modified cell lines and mosquito colonies become more common, the need to determine colony purity and detect contamination will only increase [62]. Experimental rigor and reproducibility will benefit from better community standards for mosquito cell line and colony authentication, especially [63]. ...
... Specific strains are evaluated and subjected to rigorous 'go/no go' criteria in each phase. Later efforts acknowledged the special challenges posed by the gene-drive system [132][133][134]. We encourage all scientists working with these technologies to adopt the principles outlined in these frameworks and make the essential efforts to engage potential stakeholders and end-users [135,136]. ...
... In addition, any release would raise socio-economic issues (Mitchell et al., 2017). Furthermore, measures to control a released GD, such as split drives (Edgington et al., 2020;López del Amo et al., 2019;Oberhofer et al., 2021;Terradas et al., 2021), threshold-dependant drives (Akbari et al., 2013;J. Champer et al., 2020c;Edgington and Alphey, 2017;Min et al., 2017a;Reeves and Reed, 2015), self-limiting drives (Dhole et al., 2018;Min et al., 2017b;Noble et al., 2019;Willis and Burt, 2021), inducible drives (Chae et al., 2020) or overwriting drives (Girardin et al., 2019;Heffel and Finnigan, 2019;Vella et al., 2017), at the current stage of development have not been sufficiently tested to allow firm conclusions about their effectiveness. ...
... This juvicidal insecticide can also be combined with other insecticide classes such as pyrethroids to reduce further spread of resistant alleles in mosquito populations, by reducing fecundity and longevity, sterilizing pyrethroid-resistant female strains that escape the effect of pyrethroid insecticide, thereby reducing the next generation of vectors. This strategy, where the target insect is highly resistant to one compound but susceptible to another in an insecticide mixture, has been tested in adult malaria vectors resistant for pyrethroids with great success [29]. Pyriproxyfen has also been used previously in combination with pyrethroids on bed nets to target insecticide-resistant malaria vectors. ...