Abstract: Disclosed are an enhancer, insulator, and promoter from the HS5 region in the 5′ boundary area of the locus control region of human &bgr;-like globin genes. These transcription control sequences can be used to control expression of any desired gene of interest and can be used in any vector for this purpose. The control sequences are derived from the area in and around the U3 region of a solitary endogenous retrovirus (ERV) 9 long terminal repeat (LTR). Also disclosed are methods of expressing any gene of interest. For this purpose, the control sequences can be operably linked to the gene of interest (and operably linked to each other). The disclosed enhancers, insulators, and promoters can also be used with any other control sequences. Preferably, the control sequences are used in vectors to obtain expression of a gene of interest in a cell, including cells in animals.

Abstract: A process and means for the design and the optimization of retroviral vectors transducing human .beta.-globin gene and .beta.-Locus Control Region (.beta.-LCR) derivatives, hereafter referred to as [.beta.-globin/LCR] retroviruses, which successfully meet the following criteria required for gene therapy applications: (1) stability of proviral transmission (low frequency of rearrangements similar to retroviral vectors considered stable in the art) upon infection of cell-lines and murine bone marrow cells, (2) improved viral titer, thereby allowing successful infection of bone marrow cells, and (3) high erythroid expression of the transduced human .beta.-globin gene, are described, along with specific constructs.