A SIMPLIFIED PROCEDURE FOR ISOLATION OF HIGHLY PURIFIED GENOMIC DNA

A simple and rapid procedure for thc extraction of genomic DNA involving sodium perchlorate exposure and chloroform extractions followed by SDS and Pronase E treatments is described. The method can be completed within 8 hours. Variety of tissues can be used as a source of genomic DNA (i.e. blood, amniotic fluid, tissue culture, cord blood, and organ tissue) and DNA yields of 250-350 µg/ml per 5 ml of blood with OD 260/OD 280 ratios of 1.8 can be routinely obtained with this procedure. Agarose gel clectrophoresis of the extracted DNA shows a high molecular weight species which can be directly digested with a battery of restriction enzymes. We also show that these DNA preparations can be used as templates in the polymerase chain reaction for an efficient amplification of desired DNA regions.