(Champer, 2016)

Figure 1:  Shows how Wolbachia gene drives can eliminate mosquito species.

Male killing strains of Wolbachia can be used for population suppression. However, they have a moderate rate of spread, the resistance allele generation rate is unknown and they cannot be reversed.

 Standard drives are designed to genetically alter an entire species without setting any temporal or geophysical limitations to their spread (Figure 2). For instance, Kyrou et al. (2018) have already demonstrated a method of engineering a construct targeting the Agdsx gene which led to “total population collapse” in caged mosquitoes. Daisy drive systems, also known as split drives, instead contain split up portions of CRISPR that require sequential action for the drive to operate: element A drives element B, which drives element C, and so on until the final element, which does not drive any others (Tuna et al., 2019).