Arrange the given steps of DNA finger-printing technique in correct sequence.

A. Isolation of DNA and its digestion by restriction endonuclease

B. Separation of DNA fragments by electrophoresis

C. Hybridization with labelled VNTR probe and autoradiography

D. Blotting of separated DNA fragments to synthetic membrane

Choose the correct answer from the options given below.

A,B, D,C

The correct answer is Option (2)- A,B, D,C

DNA fingerprinting involves identifying differences in some specific regions in DNA sequence called as repetitive DNA, because in these sequences, a small stretch of DNA is repeated many times.The technique of DNA Fingerprinting was initially developed by Alec Jeffreys. He used a satellite DNA as probe that shows very high degree of polymorphism. It was called a Variable Number of Tandem Repeats (VNTR). The technique, as used earlier, involved Southern blot hybridisation using radiolabelled VNTR as a probe. It included :
(i) isolation of DNA,
(ii) digestion of DNA by restriction endonucleases,
(iii) separation of DNA fragments by electrophoresis,
(iv) transferring (blotting) of separated DNA fragments to synthetic membranes, such as nitrocellulose or nylon,
(v) hybridisation using labelled VNTR probe, and
(vi) detection of hybridised DNA fragments by autoradiography.