Detecting the population dynamics of an autosomal sex ratio distorter transgene in malaria vector mosquitoes

Pollegioni, Paola, North, Ace R., Persampieri, Tania, Bucci, Alessandro, Minuz, Roxana L., Groneberg, David Alexander, Nolan, Tony ORCID: https://orcid.org/0000-0002-2982-8333, Papathanos, Philippos‐Aris, Crisanti, Andrea and Müller, Ruth (2020) 'Detecting the population dynamics of an autosomal sex ratio distorter transgene in malaria vector mosquitoes'. Journal Of Applied Ecology, Vol 57, Issue 10, pp. 2086-2096.

Preview

Text 1365-2664.13702.pdf - Published Version Available under License Creative Commons Attribution. Download (1MB) | Preview

Abstract

The development of genetically modified mosquitoes and their subsequent field release offers innovative and cost‐effective approaches to reduce mosquito‐borne diseases, such as malaria. A sex‐distorting autosomal transgene has been developed recently in G3 mosquitoes, a lab strain of the malaria vector Anopheles gambiae s.l. The transgene expresses an endonuclease called I‐PpoI during spermatogenesis, which selectively cleaves the X chromosome to result in ~95% male progeny. Following the World Health Organization guidance framework for the testing of genetically modified mosquitoes, we assessed the dynamics of this transgene in large cages using a joint experimental‐modelling approach.
We performed a four‐month experiment in large, indoor cages to study the population genetics of the transgene. The cages were set up to mimic a simple tropical environment with a diurnal light‐cycle, constant temperature, and constant humidity. We allowed the generations to overlap to engender a stable age structure in the populations. We constructed a model to mimic the experiments, and used the experimental data to infer the key model parameters.
We identified two fitness costs associated to the transgene. First, transgenic adult males have reduced fertility and, second, their female progeny have reduced pupal survival rates. Our results demonstrate that the transgene is likely to disappear in less than three years under our confined conditions. Model predictions suggest this will be true over a wide range of background population sizes and transgene introduction rates.
Synthesis and applications . Our study is in line with World Health Organization guidance recommendations in regards to the development and testing of genetically modified mosquitoes. Since the transgenic sex‐ratio‐distorter strain (Ag(PMB)1) has been considered for genetic vector control of malaria, we recorded the dynamics of this transgene in indoor‐large cage populations and modelled its post‐release persistence under different scenarios. We provide a demonstration of the self‐limiting nature of the transgene, and identified new fitness costs that will be further reduce the longevity of the transgene after its release. Finally, our study has showcased an alternative and effective statistical method for characterising the phenotypic expression of a transgene in an insect pest population.

Item Type:	Article
Subjects:	QU Biochemistry > Genetics > QU 450 General Works QX Parasitology > QX 4 General works QX Parasitology > Insects. Other Parasites > QX 510 Mosquitoes WC Communicable Diseases > Tropical and Parasitic Diseases > WC 750 Malaria
Faculty: Department:	Biological Sciences > Vector Biology Department
Digital Object Identifer (DOI):	https://doi.org/10.1111/1365-2664.13702
Depositing User:	Samantha Sheldrake
Date Deposited:	17 Jul 2020 09:02
Last Modified:	29 Oct 2020 10:43
URI:	https://archive.lstmed.ac.uk/id/eprint/15052

Statistics

View details

Actions (login required)

Edit Item