Efficient Cre-lox linearisation of BACs: applications to physical mapping and generation of transgenic animals.

Due to the size of BAC, PAC and P1 clones, it is often difficult to construct detailed restriction maps, with large number of restriction fragments leading to ambiguity of mapping data. We report the use of Cre recombinase to linearise and asymmetrically introduce label at the unique loxP site of large loxP-containing clones. Subsequent partial digestion allows the direct ordering of restriction fragments. Additionally, BAC DNA linearised using the Cre-lox system has been used successfully to generate transgenic animals.