Double-stranded human globin DNA synthesized in vitro from sickle cell mRNA has been used as a substrate for a series of restriction endonucleases. The double-stranded DNA contained full length transcripts of the alpha- and beta- globin genes. Of the 10 enzymes tested, only 3 (Hpa I, Sal I, and Kpn I) failed to cleave either alpha- or beta-DNA; 2 (Eco RI and Bam HI) cleaved only beta-DNA; 3 (HindIII, Hpa II, and Hha I) cleaved only alpha-DNA; and 2 (Hae III and Alu I) cleaved both alpha- and beta-DNAs. The selective cleavage of human globin genes by restriction endonucleases should provide a strategy for the identification and purification of DNA fragments of genomic DNA containing globin genes plus their flanking sequences, simplify the preparation of pure, chain-specific globin probes, and permit the isolation of DNA probes for specific regions of the globin genes.