Rederivation of mice is used to transfer mouse lines from one mouse facility to another within the London Community. Mice generated on the LRTGT are transferrable without rederivation into all London facilities. Additionally, rederivation can be used to establish lines derived from other institutes, or thaw existing lines that have been cryopreserved.
Generally, the LRTGT requires 6-10 pregnant females to guarantee successful rederivation. However, arrangements can be made for fewer mice.