Question

Some of the steps of DNA fingerprinting are given below. Identify the correct sequence from the options given.
$A$. Electrophoresis of DNA fragments
$B$. Hybridisation with DNA probe
$C$. Digestion of DNA by RENs
$D$. Autoradiography
$E$. Blotting of DNA fragments to nitrocellulose membrane

• A. $C-A-E-B-D$
• B. $A-C-E-D-B$
• C. $C-A-B-E-D$
• D. $A-E-C-B-D$

Answer 1

The correct option is A $C-A-E-B-D$

The DNA is cleaved to form smaller fragments. The cleavage is performed with the help of restriction enzymes which cleave at the specific recognition sites (C). The digested fragments are separated by electrophoresis (A). In this method, the DNA fragments moves from the wells towards the other pole which is positively charged. The separation occurs on the basis of charge and size of the fragments. The separated fragments are then blotted onto a nitrocellulose membrane (E). The fragments are then hybridized with probes (B). The hybridized fragments are then observed and analyzed by performing autoradiography (D).

Thus, the correct answer is option A.