Fifteen cosmids containing sequences from the human bone morphogenetic protein 1 gene (BMP1) were isolated from a cosmid library. The probe was a 483-bp DNA obtained by the reverse transcriptase-PCR method using primers designed according to the reported BMP1 sequence. When the positive cosmids were tested for chromosome fluorescence in situ hybridization, all showed signals at 8p21. The results indicated that BMP1 is not responsible for Langer-Giedion syndrome, whose putative gene has been assigned to 8q24.