Practicing Success

Target Exam

CUET

Subject

Biology

Chapter

Molecular Basis of Inheritance

Question:

Which among the following is not a feature of DNA fingerprinting ?

Options:

Digestion of DNA by ligases .

Separation of DNA fragments by electrophoresis.

Hybridisation using labelled VNTR probe .

Detection of hybridised DNA fragments by autoradiography.

Correct Answer:

Digestion of DNA by ligases .

Explanation:

The correct answer is Option (1) -Digestion of DNA by ligases .

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 as 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.