This high-quality, highly pure genomic DNA is isolated from the whole blood of disease-free sources that contain no glycogen. Human Genomic DNA is sourced from whole blood that has tested negative for HIV antibodies and Hepatitis B surface antigen. This genomic DNA is isolated by the method of Blin and Stafford (Blin, et al., 1976), and is suitable for Southern hybridization analysis and genomic library construction.