title: Oral ingestion of transgenic RIDL Ae. aegypti larvae has no negative effect on two predator Toxorhynchites species.
abstract: Dengue is the most important mosquito-borne viral disease. No specific treatment or vaccine is currently available; traditional vector control methods can rarely achieve adequate control. Recently, the RIDL (Release of Insect carrying Dominant Lethality) approach has been developed, based on the sterile insect technique, in which genetically engineered 'sterile' homozygous RIDL male insects are released to mate wild females; the offspring inherit a copy of the RIDL construct and die. A RIDL strain of the dengue mosquito, Aedes aegypti, OX513A, expresses a fluorescent marker gene for identification (DsRed2) and a protein (tTAV) that causes the offspring to die. We examined whether these proteins could adversely affect predators that may feed on the insect. Aedes aegypti is a peri-domestic mosquito that typically breeds in small, rain-water-filled containers and has no specific predators. Toxorhynchites larvae feed on small aquatic organisms and are easily reared in the laboratory where they can be fed exclusively on mosquito larvae. To evaluate the effect of a predator feeding on a diet of RIDL insects, OX513A Ae. aegypti larvae were fed to two different species of Toxorhynchites (Tx. splendens and Tx. amboinensis) and effects on life table parameters of all life stages were compared to being fed on wild type larvae. No significant negative effect was observed on any life table parameter studied; this outcome and the benign nature of the expressed proteins (tTAV and DsRed2) indicate that Ae. aegypti OX513A RIDL strain is unlikely to have any adverse effects on predators in the environment.
authors.affiliation: Medical Entomology Unit, Institute for Medical Research, Jalan Pahang, Kuala Lumpur, Malaysia.
authors.forename: Oreenaiza
authors.initials: O
authors.lastname: Nordin
authors.forename: Wesley
authors.initials: W
authors.lastname: Donald
authors.forename: Wong Hong
authors.initials: WH
authors.lastname: Ming
authors.forename: Teoh Guat
authors.initials: TG
authors.lastname: Ney
authors.forename: Khairul Asuad
authors.initials: KA
authors.lastname: Mohamed
authors.forename: Nor Azlina Abdul
authors.initials: NA
authors.lastname: Halim
authors.forename: Peter
authors.initials: P
authors.lastname: Winskill
authors.forename: Azahari Abdul
authors.initials: AA
authors.lastname: Hadi
authors.forename: Zulkamal Safi'in
authors.initials: ZS
authors.lastname: Muhammad
authors.forename: Renaud
authors.initials: R
authors.lastname: Lacroix
authors.forename: Sarah
authors.initials: S
authors.lastname: Scaife
authors.forename: Andrew Robert
authors.initials: AR
authors.lastname: McKemey
authors.forename: Camilla
authors.initials: C
authors.lastname: Beech
authors.forename: Murad
authors.initials: M
authors.lastname: Shahnaz
authors.forename: Luke
authors.initials: L
authors.lastname: Alphey
authors.forename: Derric David
authors.initials: DD
authors.lastname: Nimmo
authors.forename: Wasi Ahmed
authors.initials: WA
authors.lastname: Nazni
authors.forename: Han Lim
authors.initials: HL
authors.lastname: Lee
mesh_terms: D000330:Aedes / Q000235:genetics / Q000821:virology; D000818:Animals; D030801:Animals, Genetically Modified; D003715:Dengue / Q000517:prevention & control / Q000635:transmission; D004175:Diptera; D005260:Female; D007303:Insect Vectors / Q000235:genetics / Q000821:virology; D007814:Larva; D008297:Male; D011235:Predatory Behavior