We have been discussing Sanger DNA sequencing recently, so I wanted to talk about another method of sequencing that was used in a lab I worked in – pyrosequencing!
When I first heard of it, I assumed it had something to do with fire, but actually the “pyro” in the name comes from the fact that pyrosequencing involves the detection of pyrophosphates!
Essentially, pyrosequencing works by adding a primer to the DNA and then introducing it to nucleotides one at a time, and measuring DNA polymerase activity after nucleotide introduction through measurements of pyrophosphate release.
Since the nucleotides must add in order starting from the primer, by adding nucleotides one at a time (and degrading them immediately afterwards) and seeing which one results in an increase in pyrophosphates, you can find the sequence of the DNA strand. You can even tell if there are a few in a row based on the “intensity” in the peak of polymerase activity.
It is always incredibly exciting to hear about new technologies that make it even easier to get to the “meat” of the questions we’re trying to answer!