These mice carry loxP sites flanking exon 1-3 of Fgf21 gene. When crossed with a Cre recombinase-expressing strain, this strain is useful in eliminating tissue-specific conditional expression of Fgf21 gene.While Fgf21-Flox(Stock No.NM-CKO-00136) mice carrying the loxP sites flanking exon 1-2 of Fgf21 gene. (J:238766)