Anti-BP-1 antibodies enable researchers to detect and measure the BP-1 antigen in biological samples. This target is a reported synonym of the DLX4 gene, which encodes distal-less homeobox 4. This protein is known to function in cell differentiation and the regulation of transcription, among other biological roles. The human version of BP-1 has a canonical amino acid length of 240 residues and a protein mass of 26.3 kilodaltons, although 3 isoforms have been identified. It is reported to be localized in the nucleus of cells. BP-1 is a member of the Distal-less homeobox protein family.