A simple and efficient non-organic procedure for the isolation of genomic DNA from blood

The isolation of genomic DNA from blood typically involves digestion of nuclei with a combination of Proteinase K and SDS followed by deproteinization with organic reagents such as phenol and chloroform. Additional purification steps such as extensive dialysis, precipitation with a saturated solution of NaCl and/or absolute ethanol are then required for enzymatic analysis of the extracted DNA (1). The isolation procedure described here is both simple and rapid, eliminating the necessity for hazardous organic reagents. The method involves the incubation of nuclei with only Proteinase K at 65'C. It has been shown that Proteinase K is more active on denatured protein and that after prolonged incubation at 65C it autoinactivates (2). As a result, following a 2 hour incubation, the extracted DNA can be used directly for enzymatic analysis without any additional purification.