Arrange the steps of DNA Fingerprinting in a correct sequence:
(A) Digestion of DNA by restriction endonucleases
(B) Hybridisation using labelled VNTR probe and detection of hybridized DNA by autoradiography
(C) Isolation of DNA
(D) Separation of DNA fragments by electrophoresis and blotting
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (C), (A), (D), (B)
DNA is isolated (C), digested with restriction enzymes (A), the fragments are separated by electrophoresis and blotted (D), then hybridised with a labelled VNTR probe and detected by autoradiography (B).
Note: A similar question was also asked in CUET (UG) 2026 on 07-06-2026 (Slot 2) and on 29-05-2026 (Slot 1).
NCERT Extract:
DNA Fingerprinting – “… 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.”