Southern blot

Named after its originator Dr Edwin Southern, Southern blot analysis is the separation by movement through a non-denaturing gel such as agarose by the process of electrophoresis. Instead of agarose, the gel may also be urea or polyacrylamide and the denaturation step is therefore not necessary. The sample is denatured using sodium hydroxide and blotted with a sheet of nitrocellulose or nylon. This blot is then hybridized with a labelled probe of a DNA or RNA specific sequence to detect the specific sequences you wish to identify. Alleles in the sample are distinguished by either the fragment sizes or the strength of hybridization .