A new bacteriophage P1–derived vector for the propagation of large human DNA fragments

We have designed a P1 vector (pCYPAC−1) for the introduction of recombinant DNA into E. coli using electroporation procedures. The new cloning system, P1−derived arteficial chromosomes (PACs), was used to establish an initial 15,000 clone library with an average insert size of 130−150 kilobase pairs (kb). No chimaerism has been observed in 34 clones, by fluorescence in situ hybridization. Similarly, no insert instability has been observed after...