This transgene contains the coding sequence for enhanced green fluorescent protein (EGFP), followed by a polyadenylation signal, inserted into the mouse genomic bacterial artificial chromosome (BAC) RP23-236O14 at the ATG transcription initiation codon of the cytochrome P450, family 19, subfamily a, polypeptide 1 (Cyp19a1) gene so that expression of the reporter mRNA/protein is driven by the regulatory sequences of the mouse gene. (J:100256)