Question

A key difference between Southern and Northern blotting is that Northern blotting

• A. Uses antibodies
• B. Does not involve restriction digestion
• C. Uses protein probes
• D. Transfers proteins

Hint:

Comparison of blotting methods: \[ \boxed{ \begin{aligned} \text{Southern blot} &\rightarrow \text{DNA + Restriction digestion} \text{Northern blot} &\rightarrow \text{RNA (No restriction digestion)} \text{Western blot} &\rightarrow \text{Proteins + Antibodies} \end{aligned} } \]

Answer 1

The Correct Option is B

Step 1: Recall Southern and Northern blotting.
• Southern blotting detects DNA. Genomic DNA is first digested using restriction enzymes.
• Northern blotting detects RNA. RNA is analyzed directly and therefore does not require restriction enzyme digestion.

Step 2: Identify the distinguishing feature. Since RNA is not digested by restriction enzymes before electrophoresis, \[ \boxed{\text{Northern blotting does not involve restriction digestion}.} \] Therefore, \[ \boxed{(B)} \] is the correct answer.