homeobox
[ hō′mē-ə-bŏks′ ]
Any of various DNA sequences containing about 180 nucleotides that encode for corresponding sequences of usually 60 amino acids, called homeodomains, found in proteins that bind DNA and regulate gene transcription. Genes containing homeoboxes are found in all eukaryotic genomes and are associated with cell differentiation and bodily segmentation during embryologic development.