Southern blotting

From WikiMD's Wellness Encyclopedia

Southern blotting is a laboratory technique used in molecular biology for detection of a specific DNA sequence in DNA samples. It was named after the British biologist Edwin Southern, who first published about the procedure in 1975.

Procedure[edit | edit source]

The Southern blot procedure begins with a sample of DNA, which is then cut into smaller fragments using a restriction enzyme. These fragments are then separated by size through a process called gel electrophoresis. After the separation, the fragments are transferred to a membrane (blotting), and then they are exposed to a probe - a single DNA sequence that has been labelled with a radioactive or chemical tag. If the probe sequence is present in the sample, it will bind to the DNA fragments on the membrane, allowing for detection.

Applications[edit | edit source]

Southern blotting has many applications in molecular biology and genetics, including:

  • Identification of specific DNA sequences within a complex mixture
  • Determination of the molecular weight of a restriction fragment
  • Analysis of the structure of various fragments
  • Determination of the sequence homology among different genes

Limitations[edit | edit source]

While Southern blotting is a powerful technique, it also has some limitations. It is a time-consuming process and requires a large amount of DNA. In addition, the procedure is sensitive to changes in the DNA sequence, which can lead to false positives or negatives.

See also[edit | edit source]

Southern blotting Resources

Contributors: Prab R. Tumpati, MD