Sterility introduced by release of genetically altered males to a domestic population of Aedes aegypti at the Kenya coast

Abstract

The release of males heterozygous for one or two sex-linked translocations was effective in introducing a high level of sterility into a domestic population of Aedes aegypti at a Rabai village. The effect of the releases continued for several weeks after the release period.

PIP: Male mosquitoes, Aedes aegypti, were released at the Kenya coast to test the effectiveness of laboratory engineered mosquitoes in introducing a genetic mechanism and the ability of the mechanism to establish itself under field conditions. A triplicate of Rabai villages was selected for the experiment. In the 1st village nottreatment was made. In the 2nd village the domestic water containers were cleaned twice a week to remove larvae and pupae. Translocation males were released in the 3rd village. A mixture of 2 types of males was introduced: the single heteroxygote male selected from 78 translocations induced by irradiation in the African strains, and the double heterozygote male. Genetic analysis of the content of release samples determined quality control of released males. Fertility was also determined with females of a strain collected at Chibarani before releases began. Hatchability of eggs in all villages was counted to assay sterility in all villages. Before the releases population fluctuations in the 3 villages were monitored for 20 weeks. The release mixture had a fertility of 37% and the single heterozygote of 50%. A daily survival rate of .63 was shown for the dusted release males. There was close agreement between the monitoring for sterility for both the egg collections and the oviposition of the LB catch females. The sterility introduced into the Chibarani population was extensive.