Despite numerous advances, the field of molecular biology has often struggled to address key problems related to crop productivity and public health issues. Gene drive enables us to potentially overcome the evolutionary disadvantages of certain desirable traits and spread these traits throughout wild populations or to suppress populations of target species altogether. This, in turn, may enable the development of novel strategies. For example, to reduce or eliminate insect-borne diseases, remove invasive foreign species and even reverse the development of resistance to insecticides and herbicides, in an economically viable and environment-friendly manner2.

In humans, the malaria vector Anopheles gambiae consists of the gene double sex (Agdsx) that encodes two alternatively spliced transcripts in females and males. In the female, transcript, an exon 5 sequence is highly conserved in all Anopheles mosquitoes and disruption of this sequence through CRISPR-Cas9-based gene drive showed an intersex phenotype and caused complete sterility in females and thus controlled malaria disease3.

The Synthetic Medea gene drive system in a major worldwide crop pest, Drosophila suzukii is based on an engineered maternal “toxin” coupled with a linked embryonic “antidote,” and is capable of biasing Mendelian inheritance rates with up to 100% efficiency. Due to this biased inheritance, Medea drive is predicted to rapidly spread itself and linked cargo or payload genes, throughout a target population1.

In most agriculture farmlands, weed management is predominantly reliant on integrated weed management (IWM) strategies and herbicide application. However, the overuse and misuse of herbicides have resulted in the uptrend of herbicide-resistant weeds globally. Moreover, weedy traits that contribute to weed seed bank persistence further exacerbate the challenges in weed management. The advent of CRISPR-Cas9-based gene drive has brought into focus the potential of managing the weeds in farmlands4.

Gene drive offers a potential solution to ecological problems by altering entire populations of wild organisms. CRISPR- Cas9 mediated gene drive serves as a general and potential method for spreading altered traits through wild populations over many generations. This enables to eradication of diseases like malaria, dengue, zika, yellow fever, etc., and it provides novel ways to suppress or eliminate the weeds as well as insect-pest populations which causes significant yield losses in major agricultural crops.

References

1BUCHMAN, A., MARSHALL, J. M., OSTROVSKI, D., YANG, T. AND AKBARI, O. S., 2018, Synthetically engineered Medea gene drive system in the worldwide crop pest Drosophila suzukii. Proc. Natl. Acad. Sci., 115(18): 4725-4730.

2CHAMPER, J., BUCHMAN, A. AND AKBARI, O. S., 2016, Cheating evolution: engineering gene drives to manipulate the fate of wild populations. Nat., 17: 146-159.

3KYROU, K., HAMMOND, A. M., GALIZI, R., KRANJC, N., BURT, A., BEAGHTON, A. K., NOLAN, T. AND CRISANTI, A., 2018, A CRISPR–Cas9 gene drive targeting doublesex causes complete population suppression in caged Anopheles gambiae mosquitoes. Nat. Biotechnol., 36(11): 1062-1066.

4WONG, A. C. S., MASSEL, K., LAM, Y., HINTZSCHE, J. AND CHAUHAN, B. S., 2022, Biotechnological Road map for innovative Weed Management. Front. Plant Sci., 13: 887723.