Denaturing Gradient Gel Electrophoresis (DGGE)

Denaturing gradient gel electrophoresis (DGGE) is a robust method for point mutation detection that has been widely used for many years ( 1 ). It is a polymerase chain reaction (PCR)-based method, the principle being the altered denaturing temperature of a PCR product with a mutation compared to the wild-type product (see Chapter 6). PCR performed on DNA of an individual with a point mutation in one of two genes will lead to a mixture of different products. PCR products from both the wild-type gene and the mutated gene will be formed. These are known as the homoduplex products. The difference in melting temperature between these two products, however, is subtle. Another type of product, heteroduplexes, consisting of a wildtype strand combined with a mutant strand of DNA, will also be formed during the last cycles of the reaction. The real strength of DGGE lies in the fact that the heteroduplex PCR products will have much lower melting temperatures compared to the homoduplex PCR products, because the heteroduplexes have a mismatch ( see Fig. 1 ). These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.