Our primary objectives are to develop technology to transgenically sterilize channel catfish, Ictalurus punctatus, possessing transgenes, and to temporarily reverse the sterility as needed to produce sterile progeny for production. APPROACH: Specific objectives are to compare the following approaches to reversibly and transgenically sterile fish: 1) embryonic mis-expression 2) GnRH antisense and 3) GABA knockout. Once transgenic sterilization is achieved, our next objective is to reverse the sterility. Restoration of fertility will be attempted by applying injections of carp pituitary extract and with GnRH implants. Common carp will also be studied as an experimental model. NON-TECHNICAL SUMMARY: Transgenic, domestic, interspecific hybrid and exotic fish all have great potential for benefiting both aquaculture and recreational fishing. Many of these fish, especially transgenics, are not used because of ecological concerns. The ultimate solution to these biodiversity, genetic biodiversity and environmental risk issues for application of these fish is transgenic sterilization. Genetically engineered sterility offers great potential for 100% effective, permanent, commercial scale sterilization. We anticipate being able to produce transgenic catfish that when mated all their progeny die unless reversing compounds are applied in the hatchery to restore viability. We also anticipate production of transgenic catfish that are reproductively sterile and their progeny sterile unless exogenous reproductive hormones are applied. This will allow environmentally safe commercialization of transgenic cat fish. Success would have implication for many additional species and applications. Economic impact of a successful outcome would be millions of dollars let alone large environmental and social impacts, and will influence government policy concerning transgenic fish.
Keywords: transgenic catfish; transgenic sterilization; reproduction; embryos; channel catfish
