[Targeting of MT-II gene in mouse ES cells].

A MT-II gene targeting vector--pMT-II6.7 with 6.7kb sequences homolog to mMT-II and its flanking region has been transfected into Mespu22 with electroporation. We have got 26 positive clones from 104 G418 and Ganc clones with PCR method. From the karyotype analysis, we found two clones with 84% and 88% normal karyotype. They are clone 5-2 and 8-4. Using Southern analysis, we confirm that the two clones are homologous recombinants. These cell lines still have the pluropotential ability to differentiate both in vitro and in vivo. Now we have got a chimera mouse with cells from clone 8-4.