The human homolog of the Drosophila lady bird late gene, LBX1, is specifically expressed in the developing central nervous system and musculoskeletal system. The LBX1 gene has a restrictive expression pattern in the dorsal portion of the mantle of the spinal cord and the hindbrain of the CNS. In the developing mouse and chicken musculoskeletal system, Lbx1 is expressed in migrating limb muscle precursor cells. In addition, Lbx1 may regulate migratory patterns of limb muscle cell precursors and may be essential to dorsal identification of forelimb muscles.