Processes for isolating, amplifying, and characterizing DNA from biological materials are provided. DNA is isolated by contacting a biological material on a solid support which is preferably pre-treated with a lysing reagent. The isolation process is simple and efficient and provides a source of purified DNA without the use of harmful organic solvents such as urea and guanidine-based solvents. The purified DNA and remaining fractions of biological material may be characterized or amplified as necessary.