Several advanced techniques to detect mutations have been developed during the last years. Scanning procedures can be classified as ''physical'' and ''cleavage'' methodologies. Physical methods include Denaturing Gradient Gel Electrophoresis, Single-Strand Conformation Polymorphism and Heteroduplex Analysis while cleavage methods include RNAse A Cleavage, Chemical Mismatch Cleavage and Enzyme Mismatch Cleavage. A related technique, Protein Truncation Test, has been recently introduced.