Naturally sterile hybrid mice for the production of embryo transfer recipients

Why did we fund this project?

This award aims to refine the production of genetically modified (GM) mouse models by using sterile hybrid male mice generated by breeding two wild-type mouse strains.

Breeding programmes for GM animals require modified embryos to be transferred into recipient female mice. Prior to implantation, recipient mice must be mated with sterile males to create a pseudopregnancy in preparation for receiving the embryo. Male mice therefore either undergo surgical vasectomy under anaesthesia or require extensive breeding programmes to generate sterility. Dr Ben Davies has established a new method of generating naturally sterile mice by mating two wild-type strains of mice. Mating mice in this way results in all males being naturally sterile compared to the 12.5% in breeding programmes reducing the number of mice required.

Ben will collaborate with MRC Harwell and the University of Manchester to validate the pseudopregnancy rate of females mates with the hybrid sterile males in comparison to historical data from all three facilities. They will also determine whether the female mice produced are able to act as recipients for embryos to enable all animals from the breeding programme to be used. Hybrid embryos will be cryopreserved to enable uptake by other researchers.   

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