DNA fingerprinting techniques have the following steps. Arrange these steps in the correct order.
(A) Digestion by restriction enzyme
(B) Transferring separated DNA fragments
(C) DNA-DNA hybridization
(D) Gel Electrophoresis
Choose the correct answer from the options given below.
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (A), (D), (B), (C)
(A) Digestion by restriction enzyme — first. After the DNA is isolated, restriction enzymes cut it into fragments. Every later step works on these fragments.
(D) Gel Electrophoresis — second. The fragments are placed in a gel and an electric current is passed. They separate according to their size, the smaller ones moving farther.
(B) Transferring separated DNA fragments — third. This is blotting. The separated fragments are moved from the gel onto a membrane of nitrocellulose or nylon. Only fragments that have already been separated can be transferred.
(C) DNA-DNA hybridization — last. A labelled VNTR probe is added to the membrane. It pairs with the matching fragments, which are then seen by autoradiography as a band pattern.
NCERT Extract:
DNA Fingerprinting – …
