BioDesign Research / 2022 / Article / Tab 1

Review Article

Reflection on the Challenges, Accomplishments, and New Frontiers of Gene Drives

Table 1

RNAi-based toxin-antidote gene drive systems developed.

Drive typeSpecies/organismDesignApplicationReference

MEDEADrosophilaTransposable element vector in which the maternal germline-specific bicoid promoter drives the expression of a polycistronic transcript encoding two microRNAs (miRNAs) designed to silence expression of the gene producing the toxin, myd88Population replacement[49]
MEDEAD. suzukiiMaternal miRNA “toxin” targeting the essential gene myd88 linked to an “antidote” consisting of myd88 coding region driven by the embryo-specific bnk promoterPopulation replacement[46]
MEDEADrosophila melanogasterThe experimental design consisted of two new synthetic MEDEA elements based around the two genes dah and o-fut1, involved in cellular blastoderm formation or Notch signalingPopulation replacement[44]
Theoretical design on D. melanogasterThe theoretical design relies on environmental cues that could be used to cause a population crash. The MEDEA will be given time to spread before the cue appears and result in cue-dependent suppressionPopulation suppression
Inverse MEDEATheoretical design (not tested experimentally on any species)The designed system consisted of 2 genetic components: a zygotic toxin and maternal antidote that result in heterozygous progeny of wild-type (WT) mothers being unviablePopulation replacement[50]
UDMELD. melanogasterThe designed system consists of a construct harboring an RNAi knockdown dsRNA targeting an haploinsufficient gene RpL14 and an RNAi-insensitive RpL14 rescuePopulation replacement[43]
UDMELD. melanogasterUDMEL system consists of 2 constructs: UDMEL-1 comprises maternal toxin A and zygotic antidote B, and UDMEL-2 includes maternal toxin B and zygotic antidote A. Both toxins target essential genes for normal embryonic developmentPopulation replacement[42]
UDMELTheoretical design on Aedes aegyptiUDMEL system comprises two unlinked constructs. The maternally expressed toxin is designed on the first construct, whereas its zygotically expressed antidote is present on a separate constructPopulation replacement[47]
Combined MEDEA-underdominance systemTheoretical design (not tested experimentally on any species)The system combines MEDEA and underdominance designs in one construct on a somatic chromosomePopulation replacement[51]
Medusa (sex chromosome-associated MEDEA underdominance)Theoretical design on A. gambiaeMedusa system consisted of four components: a maternally expressed X-linked toxin and a zygotically expressed Y-linked antidote, a zygotically expressed Y-linked toxin, and a zygotically expressed X-linked antidotePopulation suppression[52]