X-shredding: Man-Made Male
In the inaugural edition of The CRISPR Journal, researchers from the University of Perugia published a method called X-Shredding, which identifies key loci of the X-chromosome in order to bias sex ratio.
X-shredding is a technique that utilizes the CRISPR-Cas9 system to target the X-chromosome. This leads to endonuclease-mediated X-chromosome shredding during spermatogenesis, which manipulates the sex ratio towards males.
There has been significant interest in this method because it may provide a feasible alternative to pesticides in the control of insect populations. Blood-feeding insects are responsible for more than half a million deaths each year worldwide. The Food and Agriculture Organization of the United Nations reports that herbivorous insects are responsible for the destruction of one fifth of the world’s crops annually.
"However, to build synthetic X-shredders based on CRISPR, the selection of gRNA targets in the form of high-copy sequence repeats on the X chromosome of a given species is difficult, since such repeats are not accurately resolved in genome assemblies and cannot be assigned to chromosomes with confidence," the researchers note...