Question

The recent techniques used for separating fragments of DNA is

• A. Northern blotting
• B. Southern blotting
• C. Western blotting
• D. Eastern blotting

Answer 1

Answer: (B)

Blotting techniques were developed to discriminate fragments of nucleic acids. These techniques involve several processes; electrophoresis is one of the processes and is used to separate fragments of DNA and RNA. In Southern blotting (named after Edward Southern) restriction enzymes cut fragments of DNA are separated by AGE or PAGE, transferred to a membrane or blot, and visualized by hybridization with labeled probes. Northern blotting separates RNA. RNA molecules are shorter and have defined lengths; cutting by restriction enzymes is not required. Western blotting does not separate nucleic acids; it separates proteins in a mixture. The proteins are usually separated with PAGE, transferred to the membrane and visualized with a labeled antibody against the proteins of interest. The eastern blot is a biochemical technique used to analyze protein post translational modifications such as lipids. Thus, Eastern blotting can be considered an extension of the biochemical technique of Western blotting.

Therefore, the correct answer is option B.