The gene responsible for the development of retinoblastoma and osteosarcoma.

The gene responsible for the formation of both retinoblastoma and osteosarcoma recently has been isolated. This represents the first human recessive cancer gene ever cloned. Structural deletions within one or both retinoblastoma gene alleles were commonly noted in the retinoblastomas and an osteosarcoma. Whether or not changes were observed at the DNA level there was either no expression or an abnormal expression of the gene in the tumor. The fact that we could detect changes in the fibroblasts of some patients with the hereditary form of retinoblastoma also indicates that the gene can be used for diagnostic purposes.