A rapid non-enzymatic method for the preparation of HMW DNA from blood for RFLP studies

In genetic linkage studies using the restriction fragment length polymorphism (RFLP) technique, it is essential to process effectively large numbers of blood samples. One of the problems faced when extracting DNA by standard methods is the requirement of deproteinizing cell digests with hazardous organic solvents like phenol, chloroform and isoamyl alcohol (1-3). The method described in this report avoids the use of any organic solvents. This is achieved by salting out the cellular proteins by dehydration and precipitation with a saturated sodium chloride solution (4). Most of the procedures also involve prolonged incubation with proteinase K (1, 4, 5). Our procedure eliminates completely the use of proteinase K treatment. The method reported here is the most economical, safe and rapid for preparation of DNA from whole blood.