Rr320^tm1.1Fier

A 1194 bp fragment spanning -10,415 to -9221 relative to the start site of mouse Hbb-y was placed into a CMV-hyTK cassette with the selectable marker flanked by inverted loxP sites and inserted into the genome by homologous recombination. Recombinase-mediated cassette exchange (RMCE) was used to create an allele without the core sequence but with the flanking sequences intact by transient expression of cre. Southern blot analysis was used to confirm the modification. (J:126615)