Ruby-eye, a new autosomal mutant in the malaria mosquito, Anopheles stephensi Liston

Anopheles stephensi, an important vector of malaria continues to be distributed widely in the Indian subcontinent. This vector species has developed resistance for various insecticides. Therefore, it is desirable to develop alternate strategy, which does not involve resistance. In order to develop such strategy, it is mandatory that genetic studies of concerned vector species should be established. This paper describes the isolation and genetic studies of an eye colour mutant, ruby-eye (ru), and linkage studies involving another autosomal recessive mutant greyish brown larva (grb ru) in A. stephensi.

The stocks of mutants ruby-eye (ru), greyish brown (grb ru) and wild type mosquitoes were maintained in the laboratory. Crosses were made between the wild type and mutant to determine the mode of inheritance of ruby-eye. For linkage studies crosses were made between the mutant ruby-eye and another autosomal recessive mutant greyish brown larva. The percentage cross over was calculated for the genes linkage relationship for ru and grb ru.

Results of crosses between mutant and wild type show that the inheritance of ruby-eye in A. stephensi is monofactorial in nature. The ru allele is recessive to wild type and is autosomal. The linkage studies showed no linkage between grb and ru.

The mutant ru represents an excellent marker for A. stephensi as it expresses in all the life stages with complete penetrance and high viability. This mutant can be used extensively to conduct basic and applied research.