Bone morphogenetic protein (BMP) is one of the most promising candidates for bone regeneration therapy. Heterodimers of BMP family proteins, such as BMP-2/4 or BMP-2/7, are well known to have stronger osteoinduction activity than BMP homodimers. Here, we constructed a double gene cassette vector encoding BMP-2 and BMP-7, pCAGGS-BMP-2/7, and examined its potential for osteoinduction in vitro and in vivo. Expression of the pCAGGS-BMP-2/7 vector induced osteogenic differentiation in various cell lines with the same efficiency as BMP-2 and BMP-7 co-expressed from separate vectors. Moreover, the pCAGGS-BMP-2/7 vector strongly induced bone formation in rat skeletal muscle when introduced by in vivo electroporation, compared with BMP-2 or BMP-7 alone. Thus, our BMP-2/7 double gene cassette vector, or some variation of it, may be applicable for the future clinical induction of bone formation, because it does not require multiple vectors or complicated preparation. (C) 2009 Elsevier Inc. All rights reserved.