Process and apparatus for extracting DNA from test samples

A process and apparatus for extracting DNA, which has relatively high molecular weight, from test samples and particularly from human whole blood samples; the extracted DNA is of usable volume and concentration, and is of such purity as to permit conventional restriction by a number of enzymes without the need for further purification. The apparatus consists essentially of an agarose gel disc, typically 5 mm. thick by 31 mm. in diameter, supported between two 8 micrometer polycarbonate filters in an electric field. Further, the method involves the loading of a suitably treated blood sample onto the top face of the agarose gel disc and then applying an electric field. Of the constituent parts of the treated blood, the DNA molecules are the largest with regard to molecular weight. Consequently, their passage through the agarose gel disc, under the force of the electric field, is impeded. All other constituent parts of the treated blood pass relatively rapidly through the disc and are removed. The DNA is then collected, and suitably stored in readiness for analysis.