The expression of a foreign gene in salmon embryos

DNA which contained the E. coli β-galactosidase gene fused to the mouse metallothionein promoter was microinjected into fertilized ova from Atlantic salmon (Salmo salar). Nine to 14 weeks later, embryos which derived from the injected ova were shown to express β-galactosidase activity. The DNA which had been microinjected into the ova was also present in some embryos after 14 weeks development. It was not possible to show if the injected DNA had in fact integrated into the chromosomes. This study provides evidence for the functioning of the mouse metallothionein promoter in vivo in salmon embryos.