Question

Which of the following is the first step of the Southern blotting procedure?

1) hybridizing the DNA with a radioactive probe
2) separating the DNA fragments using gel electrophoresis
3) using the blot to expose photographic film
4) digesting the DNA with a restriction enzyme
5) transferring the DNA to a blot

Answer 1

The first step in Southern blotting is digesting the DNA with a restriction enzyme, which prepares the DNA for gel electrophoresis.

Step-by-step explanation:

The first step of the Southern blotting procedure is digesting the DNA with a restriction enzyme. This step is crucial because it fragments the genomic DNA, preparing it for subsequent separation via gel electrophoresis. Southern blotting is a molecular biology technique used to detect specific DNA sequences in DNA samples by separating DNA fragments, transferring them to a nylon membrane, and then hybridizing them with a labeled DNA probe.