This is a database of peer-reviewed literature that focuses on Genetic Biocontrol research. The latest are shown here.
Gene drive-mediated population elimination for biodiversity conservation. When you come to a fork in the road, take it
Background
Gene drive occurs when alleles of genes, multigene cassettes, or large chromosomal regions are transmitted to fertile progeny at greater-than-Mendelian frequencies (50%). Gene drive can be used to bring about population suppression or elimination when the rate at which the drive element increases in frequency outpaces a fitness cost induced by its presence, and the population is driven to an unfit state. Much work has focused on applications involving mosquito vectors of human disease. Many other applications have their origin in the global problem of invasive species, and thinking about how to ameliorate the many harms they are associated with: food insecurity, human disease, economic loss, environmental degradation, and loss of biodiversity.
Hay, B. A., & Guo, M. (2022). Gene drive-mediated population elimination for biodiversity conservation. When you come to a fork in the road, take it. Proceedings of the National Academy of Sciences, 119(51), e2218020119.
Developing the radiation-based sterile insect technique (SIT) for controlling Aedes aegypti: identification of a sterilizing dose
Background
The sterile insect technique (SIT) is emerging as a tool to supplement traditional pesticide-based control of Aedes aegypti, a prominent mosquito vector of microbes that has increased the global burden of human morbidity and mortality over the past 50 years. SIT relies on rearing, sterilizing and releasing large numbers of male mosquitoes that will mate with fertile wild females, thus reducing production of offspring from the target population.
Chen, C., Aldridge, R. L., Gibson, S., Kline, J., Aryaprema, V., Qualls, W., … & Hahn, D. A. (2023). Developing the radiation‐based sterile insect technique (SIT) for controlling Aedes aegypti: identification of a sterilizing dose. Pest Management Science, 79(3), 1175-1183.
A CRISPR endonuclease gene drive reveals distinct mechanisms of inheritance bias
Background
CRISPR/Cas gene drives can bias transgene inheritance through different mechanisms. Homing drives are designed to replace a wild-type allele with a copy of a drive element on the homologous chromosome. In Aedes aegypti, the sex-determining locus is closely linked to the white gene, which was previously used as a target for a homing drive element (wGDe). Here, through an analysis using this linkage we show that in males inheritance bias of wGDe did not occur by homing, rather through increased propagation of the donor drive element.
Verkuijl, S. A., Gonzalez, E., Li, M., Ang, J. X., Kandul, N. P., Anderson, M. A., … & Alphey, L. (2022). A CRISPR endonuclease gene drive reveals distinct mechanisms of inheritance bias. Nature Communications, 13(1), 7145.
Why Wolbachia-induced cytoplasmic incompatibility is so common
Background
Wolbachia are obligately intracellular alphaproteobacteria that infect approximately half of all insect species. Maternal inheritance of these endosymbionts produces selection to enhance female fitness. In addition to mutualistic phenotypes such as nutrient provisioning, Wolbachia produce various reproductive manipulations that favor infected females. Most common is cytoplasmic incompatibility, namely reduced embryo viability when Wolbachia-infected males fertilize Wolbachia-uninfected females. The regular loss of cytoplasmic incompatibility indicates this phenotype is not favored by natural selection among Wolbachia variants within host populations.
Turelli, M., Katznelson, A., & Ginsberg, P. S. (2022). Why Wolbachia-induced cytoplasmic incompatibility is so common. Proceedings of the National Academy of Sciences, 119(47), e2211637119.
Driving down malaria transmission with engineered gene drives
Background
The last century has witnessed the introduction, establishment and expansion of mosquito-borne diseases into diverse new geographic ranges. Malaria is transmitted by female Anopheles mosquitoes. Despite making great strides over the past few decades in reducing the burden of malaria, transmission is now on the rise again, in part owing to the emergence of mosquito resistance to insecticides, antimalarial drug resistance and, more recently, the challenges of the COVID-19 pandemic, which resulted in the reduced implementation efficiency of various control programs. The utility of genetically engineered gene drive mosquitoes as tools to decrease the burden of malaria by controlling the disease-transmitting mosquitoes is being evaluated.
Garrood, W. T., Cuber, P., Willis, K., Bernardini, F., Page, N. M., & Haghighat-Khah, R. E. (2022). Driving down malaria transmission with engineered gene drives. Frontiers in Genetics, 13.
Leveraging a natural murine meiotic drive to suppress invasive populations
Background
Invasive rodents pose a significant threat to global biodiversity, contributing to countless extinctions, particularly on islands. Genetic biocontrol has considerable potential to control invasive populations but has not been developed in mice. Here, we develop a suppression gene drive strategy for mice that leverages a modified naturally occurring element with biased transmission to spread faulty copies of a haplosufficient female fertility gene (tCRISPR). In silico modeling of island populations using a range of realistic parameters predicts robust eradication. We also demonstrate proof of concept for this strategy in laboratory mice. This work marks a significant step toward the development of a gene drive for the suppression of invasive mice.
Gierus, L., Birand, A., Bunting, M. D., Godahewa, G. I., Piltz, S. G., Oh, K. P., … & Thomas, P. Q. (2022). Leveraging a natural murine meiotic drive to suppress invasive populations. Proceedings of the National Academy of Sciences, 119(46), e2213308119.
A sterile insect technique pilot trial on Captiva Island: defining mosquito population parameters for sterile male releases using mark–release–recapture
Background
The sterile insect technique (SIT), which involves area-wide inundative releases of sterile insects to suppress the reproduction of a target species, has proven to be an effective pest control method. The technique demands the continuous release of sterilized insects in quantities that ensure a high sterile male:wild male ratio for the suppression of the wild population over succeeding generations.
Carvalho, D. O., Morreale, R., Stenhouse, S., Hahn, D. A., Gomez, M., Lloyd, A., & Hoel, D. (2022). A sterile insect technique pilot trial on Captiva Island: defining mosquito population parameters for sterile male releases using mark–release–recapture. Parasites & Vectors, 15(1), 1-14.
Assessing single-locus CRISPR/Cas9-based gene drive variants in the mosquito Aedes aegypti via single-generation crosses and modeling
Background
The yellow fever mosquito Aedes aegypti is a major vector of arthropod-borne viruses, including dengue, chikungunya, and Zika viruses. A novel approach to mitigate arboviral infections is to generate mosquitoes refractory to infection by overexpressing antiviral effector molecules. Such an approach requires a mechanism to spread these antiviral effectors through a population, for example, by using CRISPR/Cas9-based gene drive systems.
Reid, W., Williams, A. E., Sanchez-Vargas, I., Lin, J., Juncu, R., Olson, K. E., & Franz, A. W. (2022). Assessing single-locus CRISPR/Cas9-based gene drive variants in the mosquito Aedes aegypti via single-generation crosses and modeling. G3, 12(12), jkac280.
CRISPR Cas9 mediated knockout of sex determination pathway genes in Aedes aegypti
Background
The vector role of Aedes aegypti for viral diseases including dengue and dengue hemorrhagic fever makes it imperative for its proper control. Despite various adopted control strategies, genetic control measures have been recently focused against this vector. CRISPR Cas9 system is a recent and most efficient gene editing tool to target the sex determination pathway genes in Ae. aegypti.
Zulhussnain, M., Zahoor, M. K., Ranian, K., Ahmad, A., & Jabeen, F. (2023). CRISPR Cas9 mediated knockout of sex determination pathway genes in Aedes aegypti. Bulletin of Entomological Research, 113(2), 243-252.
Points to consider in seeking biosafety approval for research, testing, and environmental release of experimental genetically modified biocontrol products during research and development
Background
Novel genetically modified biological control products (referred to as “GM biocontrol products”) are being considered to address a range of complex problems in public health, conservation, and agriculture, including preventing the transmission of vector-borne parasitic and viral diseases as well as the spread of invasive plant and animal species. These interventions involve release of genetically modified organisms (GMOs) into the environment, sometimes with intentional dissemination of the modification within the local population of the targeted species, which presents new challenges and opportunities for regulatory review and decision-making.
Tonui, W. K., Ahuja, V., Beech, C. J., Connolly, J. B., Dass, B., Glandorf, D. C. M., … & Romeis, J. (2022). Points to consider in seeking biosafety approval for research, testing, and environmental release of experimental genetically modified biocontrol products during research and development. Transgenic Research, 31(6), 607-623.