Question

A technique for transferring denatured DNA molecules that have been separated electrophoretically from a gel to a matrix (such as a nitrocellulose or nylon membrane) on which a hybridization assay can be performed is called

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

Hint:

Use the mnemonic \textbf{S-N-O-W D-R-O-P}:

\textbf{S}outhern $\rightarrow$ \textbf{D}NA
\textbf{N}orthern $\rightarrow$ \textbf{R}NA
\textbf{O} $\rightarrow$ \textbf{O} (nothing)
\textbf{W}estern $\rightarrow$ \textbf{P}rotein
This helps you remember which blotting technique corresponds to which macromolecule.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Blotting techniques transfer macromolecules (DNA, RNA, proteins) from an electrophoresis gel to a solid membrane for detection.
Step 2: Detailed Explanation:
The specific names of the blotting techniques correspond to the type of molecule being detected:


Southern blotting: Used to detect specific DNA sequences. The process described in the question—separating DNA on a gel and transferring it to a membrane for hybridization—is the definition of a Southern blot.

Northern blotting: Used to detect specific RNA sequences.

Western blotting: Used to detect specific proteins using antibodies.

Eastern blotting: A less common technique for detecting post-translational modifications.

Step 3: Final Answer:
The technique for transferring separated DNA from a gel to a membrane is called Southern blotting.