Developmentally-regulated GTP-binding protein 1 (DRG1) is a member of the GTP1/OBG family. DRG1 has a role in cell proliferation and differentiation, as well as in apoptosis, proposing a role in tumor formation and metastasis. Expression of the DRG1 was considerably reduced in breast tumor cells, particularly in patients with lymph node or bone metastasis as compared to those with localized breast cancer. The DRG1 protein is expressed at high levels in the heart, kidney and skeletal muscle and at lower levels in the brain, liver, placenta, lung, colon and spleen.