What is Nucleic Acid Detection and Analysis?

Nucleic Acid Detection and Analysis is a broad term for describing techniques that scientist use to find certain nucleic acid sequences in a specimen. This is useful because it can be helpful in finding whether or not an organism has a certain gene present, characterizing species, and diagnosing pathogens. There are several techniques that one can employ to do detection and analysis. One in particular is the Northern Blot.

A Northern Blot is done by collecting RNA from a sample of homogenized tissue (Southern Blots are done for DNA). The tissue is then isolated using electrophoresis. A membrane is then placed onto the gel (which is placed on a sponge in salt water) and pressure applied. This will blot the RNA onto the membrane. Probes (pieces of nucleic acids that are complementary to target you are looking for) are then placed onto the membrane and washed off. If a probe encounters the target RNA it should stick, preventing it from being washed off. An x-ray film is then used to detect if any probes are still left on the membrane therefore confirming whether the target RNA was present or not.

P.S. Something funny I found (or at least I think it is). Northern (along with Eastern and Western) blots are not named for any cardinal directions. They are named as a cheeky reference to their similarity to Southern blots, invented by Edwin Southern.