Gbx2 expression was demonstrated in undifferentiated embryonic stem cells but was downregulated in differentiated cell populations. In the embryo, Gbx2 expression was detected before primitive streak formation, in the inner cell mass of the preimplantation embryo.

The nucleotide sequence of the cDNA clone encodes a protein of 347 amino acid residues. The amino acid sequence of the GBX2 homeodomain was found to be identical (100%) to that of the homologous gene, Gbx2, expressed in the developing mouse embryo and virtually identical (97%) to a gene expressed in the developing chick embryo, CHox7. the mouse Gbx2 gene contains a single intron, a feature of the human GBX2 gene.