Fig. 2. The Msx2 BMP-responsive region is highly conserved among mammals. BLAST was used to search for sequence identity between the murine Msx2 locus and Msx2 loci of other vertebrates. Alignments of a 480 bp homology block are shown in different mammalian species, with coordinates of transcription start sites at left. Sequence differences relative to chimpanzee are in bold. The underlined sequence (164-246) is a tandem duplication; bases in blue are those that differ between the two duplicated copies. Shaded areas show consensus binding sites for the indicated transcription factors. Boundaries of transgenes are indicated by brackets below the sequence. Putative Smad-binding sites within the 52 bp transgene are underlined. The boxed area indicates a putative Fox/Hnf site matching the consensus (C/A)(T/C)(C/A)AA(T/C)A in 5/7 positions.