AbstractThe Wnt family of glycoproteins is involved in numerous developmental and disease processes in higher eukaryotes, exerting their action by binding to cell‐surface receptors. In the extracellular space, Wnts are negatively regulated by secreted antagonists that either bind to the receptors directly (Dkk1) or to Wnt molecules themselves (Sfrp‐FRZB family), preventing its subsequent binding to the receptor. Here we report on a transgenic mouse expressing Cre under the control of the mouse Frzb promoter element. Analysis of the Cre expression was carried out at 10.5 and 14.5 dpc using the ROSA26R mouse line. Expression of the transgenic construct was detected in the limbs, the heart, the nasal epithelium, bone, whiskers, and around the orbita of the eye. The mouse could be used for conditional gene modification in those tissues. genesis 40:200–204, 2004. © 2004 Wiley‐Liss, Inc.