GFP was inserted in-frame into exon 2. In this derivative of Hoxa13tm1Mrc, Cre-mediated recombination in the germline removed an adjacent floxed neomycin resistance cassette. The expression pattern in E10.5-E13.5 embryos of a Hoxa13-GFP fusion protein from this allele recapitulates the published Hoxa13 mRNA expression pattern. (J:72301)