Beyond mendelian inheritance: Gene drive promises insect control
Mosquitoes and other biting insects are responsible for transmitting debilitating diseases causing hundreds of thousands of deaths every year. These insects are responsible for the dispersion of diseases such as malaria, chikungunya, dengue fever, yellow fever and many more, including as the recent Zika outbreak. One of the most successful ways to combat the transmission of insect-borne disease is the control of insect populations. If mosquitoes were less prevalent, these diseases would not be spread as easily.
In a recent publication (Gantz and Bier, 2015)from the laboratory of Ethan Bier at the University of California, San Diego, USA, authors Gantz and Bier developed a system in fruit flies that could control insect populations. This method is based on the recently developed CRISPR-CAS9 technology, which enables genetic editing. The authors cleverly used this approach to create a self-replicating genetic system, which allows for the spread of newly introduced genes in a wild population.
Normally, living organisms inherit from each of their parents only one of two chromosomes. In case of a defective gene the progeny will have trouble reproducing, thus making it hard to perpetuate certain mutations unless they are neutral or beneficial. With the approach used by the authors, it is now possible to disperse whichever gene is desired, since the newly invented system is self-propagating. Thanks to this CRISPR-CAS9 based methodology, an insect inheriting one chromosome carrying this transgene will also transform its other chromosome into a certain mutation.
In the current study the authors exemplify this technology by spreading a gene (yellow) coding for a fly pigment. However, this approach could instead be used to disperse a transgene that makes insects lay fewer eggs, thus reducing the target insect population overall. This technique could also be used to fight agricultural pests. One advantage of this technique is that it targets a single species, while chemical pesticides typically kill many types of insects, including those that are beneficial such as bees.
Citation: Gantz, V. M. and Bier, E. (2015) ‘The mutagenic chain reaction: A method for converting heterozygous to homozygous mutations’, Science, 348(6233), pp. 442–444. doi: 10.1126/science.aaa5945.
In a recent publication (Gantz and Bier, 2015)from the laboratory of Ethan Bier at the University of California, San Diego, USA, authors Gantz and Bier developed a system in fruit flies that could control insect populations. This method is based on the recently developed CRISPR-CAS9 technology, which enables genetic editing. The authors cleverly used this approach to create a self-replicating genetic system, which allows for the spread of newly introduced genes in a wild population.
Normally, living organisms inherit from each of their parents only one of two chromosomes. In case of a defective gene the progeny will have trouble reproducing, thus making it hard to perpetuate certain mutations unless they are neutral or beneficial. With the approach used by the authors, it is now possible to disperse whichever gene is desired, since the newly invented system is self-propagating. Thanks to this CRISPR-CAS9 based methodology, an insect inheriting one chromosome carrying this transgene will also transform its other chromosome into a certain mutation.
In the current study the authors exemplify this technology by spreading a gene (yellow) coding for a fly pigment. However, this approach could instead be used to disperse a transgene that makes insects lay fewer eggs, thus reducing the target insect population overall. This technique could also be used to fight agricultural pests. One advantage of this technique is that it targets a single species, while chemical pesticides typically kill many types of insects, including those that are beneficial such as bees.
Citation: Gantz, V. M. and Bier, E. (2015) ‘The mutagenic chain reaction: A method for converting heterozygous to homozygous mutations’, Science, 348(6233), pp. 442–444. doi: 10.1126/science.aaa5945.