Question

Arrange in a sequence the given protocol for DNA fingerprinting:
(a) Denaturating DNA

(b) Blotting

(c) Extraction of DNA

(d) Fragmenting DNA

(e) Separation of DNA fragments by electrophoresis

(f) Hybridisation with the probe

(g) Exposure on film to make a DNA fingerprint

• A. c $\to$ d $\to$ e $\to$ a $\to$ b $\to$ f $\to$ g
• B. a $\to$ c $\to$ d $\to$ e $\to$ b $\to$ f $\to$ g
• C. a $\to$ c $\to$ b $\to$ d $\to$ e $\to$ f $\to$ g
• D. c $\to$ e $\to$ d $\to$ b $\to$ a $\to$ f $\to$ g

Answer 1

The correct option is A c $\to$ d $\to$ e $\to$ a $\to$ b $\to$ f $\to$ g

DNA finger printing involves following steps:

1. Isolation of DNA from sample cell.

2. If DNA is less in amount, it can be amplified using Polymerase Chain Reaction(PCR).

3. Digestion of this DNA by Restriction EndoNucleases (RENs).

4. These DNA fragments are electrophoresed in agarose gel.These fragments can be visualized by EtBR-UV system.

5. Separated DNA fragments are transferred to nitrocellulose membrane using Southern blotting.

6. Probing for VNTRs is done using labelled DNA probes.

7. The hybridised fragments can be detected by autoradiography.

Hence, The correct option is A.