(A) Location of ameloblastin (AMBN) and enamelin (ENAM) on human chromosome 4. (B) Homologous region on chicken chromosome 4. The position of several gene clusters is different in both chromosomes. Two gene inversions (curved arrows) have occurred in the candidate region putatively housing AMBN and ENAM leading to two likely locations for these genes on chicken chromosome: either adjacent to sulfotransferase 1E1 (SULT1E1) or to immunoglobulin J peptide. See the NCBI website for gene descriptions corresponding to the symbols.
Sire et al. BMC Evolutionary Biology 2008 8:246 doi:10.1186/1471-2148-8-246