To a solution containing DNA/RNA add the following components: 1/10 vol. of Sodium Acetate 3 M (pH 5.0) 20-50 µg glycogen (optional) 2 vol. of absolute EtOH or 1 vol. of isopropanol Mix well and let stand overnight at –20oC or for 20 min. at –70oC Precipitate nucleic acid by centrifuging at max. speed for 15 min Pour out supernatant and add 500 µl EtOH 75%. Centrifuge for 2 min. at max. speed Pour out supernatant and air dry the pellet