An FRT-flanked selection vector containing a neomycin resistance gene and a single 5' loxP site was inserted upstream of exon 2 of the Clec1b gene and a second loxP site was inserted downstream of exon 8 of the Clec9a gene. The selection cassette and exons 2 through 6 of Clec1b and all of the Clec9a gene were subsequently removed from properly targeted mice by crossing to transgenic mice carrying Tg(EIIa-cre)C5379Lmgd. (J:94077)