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

• Published in: Acta tropica Vol. 132; pp. S178 - S187
• Main Authors: Gilles, Jeremie R.L., Schetelig, Marc F., Scolari, Francesca, Marec, František, Capurro, Margareth L., Franz, Gerald, Bourtzis, Kostas
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.04.2014
• Subjects: Animals; Coordinated Research Project (CRP); Culicidae - genetics; Culicidae - growth & development; Female; Female elimination; Genetic sexing strains (GSS); Insect Vectors; Male; Molecular Biology; Mosquito Control - methods; Pest Control, Biological - methods; Sex Characteristics; Sterile insect technique (SIT); Sterilization - methods; Vector control; Sterile insect technique (SIT); Vector control; Genetic sexing strains (GSS); Female elimination; Coordinated Research Project (CRP)
• ISSN: 0001-706X; 1873-6254
• DOI: 10.1016/j.actatropica.2013.08.015

A sterile insect technique programme requires female elimination, achievable using a classical or transgenic genetic sexing strain. Interim measures benefiting from mechanical or behavioural separation are also needed. •Application of the sterile insect technique in mosquitoes requires all-male release.•Genetic sexing strains, a very efficient means of female elimination, are discussed.•Developing a genetic sexing strain for all major vectors will be a lengthy process.•Interim measures that use mechanical separation or based on behaviour are proposed. 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.