Cryopreservation of transgenic mice.

Advances in cryopreservation enable one to freeze embryos without the use of a programmable freezing machine or complex protocols. These methods achieve high rates of survival when mouse embryos are frozen. Understanding the factors that influence the survival of cryopreserved embryos can aid troubleshooting and in adapting freezing strategies from mice to other species. Frozen stocks of transgenics can be maintained indefinitely in liquid nitrogen. Cryopreservation of these valuable animals not only protects them from environmental catastrophes, but also is an economical method of storing lines for future detailed analysis.