Figure 1.

The targeted disruptions of the mouse eosinophil MBP-1 and EPX genes. Restriction maps of the targeting constructs and the MBP-1 and EPX loci before and after the homologous recombination events occurring in the embryonic stem cells that were used to generate the corresponding knockout strains of MBP-1^−/− and EPX^−/− mice, respectively. As noted, the genes encoding these abundant secondary granule proteins are located on different mouse chromosomes, facilitating the production of double knockout mice through selective breeding strategies of the single knockout strains of mice; offspring genotypes are subject to Mendelian inheritance patterns based on the genotype of the breeding dam and sire. Various polymerase chain reaction (PCR) primer combinations used to identify and confirm the genotype of individual mice are shown for each loci (P₁-P₅, MBP-1 and P₁-P₄, EPX).