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Transgenic Aedes aegypti Mosquitoes Transfer Genes into a Natural Population.

ABSTRACT: In an attempt to control the mosquito-borne diseases yellow fever, dengue, chikungunya, and Zika fevers, a strain of transgenically modified Aedes aegypti mosquitoes containing a dominant lethal gene has been developed by a commercial company, Oxitec Ltd. If lethality is complete, releasing this strain should only reduce population size and not affect the genetics of the target populations. Approximately 450 thousand males of this strain were released each week for 27 months in Jacobina, Bahia, Brazil. We genotyped the release strain and the target Jacobina population before releases began for >21,000 single nucleotide polymorphisms (SNPs). Genetic sampling from the target population six, 12, and 27-30 months after releases commenced provides clear evidence that portions of the transgenic strain genome have been incorporated into the target population. Evidently, rare viable hybrid offspring between the release strain and the Jacobina population are sufficiently robust to be able to reproduce in nature. The release strain was developed using a strain originally from Cuba, then outcrossed to a Mexican population. Thus, Jacobina Ae. aegypti are now a mix of three populations. It is unclear how this may affect disease transmission or affect other efforts to control these dangerous vectors. These results highlight the importance of having in place a genetic monitoring program during such releases to detect un-anticipated outcomes.

SUBMITTER: Evans BR

PROVIDER: S-EPMC6736937 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Transgenic Aedes aegypti Mosquitoes Transfer Genes into a Natural Population.

Evans Benjamin R BR Kotsakiozi Panayiota P Costa-da-Silva Andre Luis AL Ioshino Rafaella Sayuri RS Garziera Luiza L Pedrosa Michele C MC Malavasi Aldo A Virginio Jair F JF Capurro Margareth L ML Powell Jeffrey R JR

Scientific reports 20190910 1

In an attempt to control the mosquito-borne diseases yellow fever, dengue, chikungunya, and Zika fevers, a strain of transgenically modified Aedes aegypti mosquitoes containing a dominant lethal gene has been developed by a commercial company, Oxitec Ltd. If lethality is complete, releasing this strain should only reduce population size and not affect the genetics of the target populations. Approximately 450 thousand males of this strain were released each week for 27 months in Jacobina, Bahia, ...[more]

PMID: 31506595

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Dataset Information

Transgenic Aedes aegypti Mosquitoes Transfer Genes into a Natural Population.

Publications

Transgenic Aedes aegypti Mosquitoes Transfer Genes into a Natural Population.

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