Towards mosquito sterile insect technique programmes: Exploring genetic, molecular, mechanical and behavioural methods of sex separation in mosquitoes

Abstract

When considering a mosquito release programme, one of the first issues to be addressed is how to eliminate/separate the females. The greatest number of options might eventually be available for those who can use transgenic mosquitoes, but the inherent characteristics of the target species may also provide possibilities for interim measures until more efficient methods can be developed. Differences in intrinsic size, in behaviour and in development rate between females and males are often available and useful for sexing. Efficient species-specific systems for eliminating females at the embryo stage have been developed, but most have since been discarded due to lack of use. Ideal systems specifically kill female embryos using some treatment that can be manipulated during production. Such killing systems are far more efficient than using intrinsic sexual differences, but they systems require selectable genetic markers and sex-linkage created by rare random chromosomal rearrangements. While intrinsic sexual differences should not be considered as long-term candidates for the development of robust and efficient sexing approaches, in the absence of these, the accessibility and integration of less efficient systems can provide a stop-gap measure that allows rapid start up with a minimum of investment. The International Atomic Energy Agency is funding over a 5 year period (2013-2018) a new Coordinated Research Project on "Exploring Genetic, Molecular, Mechanical and Behavioural Methods of Sex Separation in Mosquitoes" to network researchers and to address the critical need of genetic sexing strains for the implementation of the sterile insect technique (using radiation-sterilised or transgenic male mosquitoes) and for insect incompatibility technique programmes against disease-transmitting mosquitoes.

The Anopheles arabiensis genetic sexing strain ANO IPCL1 and its application potential for the sterile insect technique in integrated vector management programmes

“…This can be achieved by exploiting behavioural or biological differences between the sexes, or by the development of genetic sexing strains (GSS) (Papathanos et al, 2009;Gilles et al, 2014). Classical GSSs have been based on an artificially induced sex linkage of a selectable (and in some cases conditionally lethal) genetic marker (Curtis et al, 1976).…”

The Potential Use of Wolbachia-Based Mosquito Biocontrol Strategies for Japanese Encephalitis

“…tritaeniorhynchus . Alternative mosquito control strategies that aim to suppress the mosquito population, such as the sterile insect technique (SIT) [72,73] or release of insects with a dominant lethal (RIDL) [74,75], could have a potential role in JE control. However, the likely need for repeated release of large numbers of sterile males for individual outbreaks of JE over a large transmission area would also pose both logistical and financial difficulties.…”

Dengue fever virus in Pakistan: effects of seasonal pattern and temperature change on distribution of vector and virus

“…This program was less successful because of somatic damage and performance reduction by insects . But modern genetics has a potential to overcome this problem by introducing self‐limiting genes that are engineered . This system looked good, and it shared clean specific species characteristics and the advantage of the ability to seek females from released males.…”