Frs2^tm1Fwan

Exon 5 was flanked by loxP sites with one loxP site placed immediately upstream and the other placed 600 bp downstream. A FRT-flanked neo selection cassette was placed between the exon and the downstream loxP site. Mice were crossed with FLP expressing knock-in mice to remove the neo cassette. Insertion of the loxP sites were presumed not to effect gene expression because homozygote mice were born at Mendelian frequencies. (J:128712)