Figure 1

Generation of the Pax6 conditional allele. (A) Targeting strategy showing the insertion of loxP sites into introns 4 and 6 of murine Pax6, flanking exons that encode the paired type homeodomain. The final floxed Pax6 (Pax6^loxP) and floxed null (Pax6^loxPΔ) alleles are shown. (B, C) Correct targeting of the Pax6 locus in a series of embryonic stem cell clones was confirmed by Southern blot hybridization with probes (indicated by colored bars) proximal (B) and distal (C) to the insertion site; wt = wild type. (D) PCR amplification was used to genotype the Pax6^loxPallele using primer set PCR1 and Pax6^loxPΔalleles using primer set PCR2 (positions of primers are indicated in (A)).