Using sterile salmon in production can prevent such unwanted genetic introgression.
The salmon industry is currently threatened by parasites such as sea lice and escapees, which negatively affect wild populations by interbreeding 1, 2.
CIRCLE OF 8 DND FREE
The method presented here opens a possibility for large-scale production of germ-cell free Atlantic salmon offspring through the genetically sterile broodstock which can pass the sterility trait on the next generation.Īs the global expansion of the salmon aquaculture industry rapidly continues, the aim of optimizing aquaculture methods to improve food production while reducing the environmental impacts of the industry is of growing demand. We found that rescued one-year-old fish contained germ cells, type A spermatogonia in males and previtellogenic primary oocytes in females. To achieve this, we co-injected the wild-type (wt) variant of salmon dnd mRNA together with CRISPR-Cas9 constructs targeting dnd into 1-cell stage embryos. Here, we report a rescue approach for producing germ cells in Atlantic salmon dnd crispants. The lack of germ cells in the resulting dnd crispants, thus, prevents reproduction and inhibits subsequent large-scale production of sterile fish.
A novel approach in which to achieve sterility is to produce germ cell-free salmon, which can be accomplished by knocking out the dead-end ( dnd) gene using CRISPR-Cas9. So far, the only commercially used methodology for producing sterile fish is triploidization. Using sterile fish in commercial aquaculture operations is, therefore, a sustainable strategy for bio-containment. Genetic introgression of escaped farmed Atlantic salmon ( Salmo salar) into wild populations is a major environmental concern for the salmon aquaculture industry.