A common term in genetics research these days is Massively Parallel Sequencing. It’s been around for a number of years, but it still gets researchers very excited. It’s not often communicated to the lay person, because, well… it sounds kinda goofy, and the details are a bit hard to grasp. But let me try to give an introduction.
Let’s start with the most important part: Sequencing. When we say sequencing in the the context of genetics, what we mean is that we want to know the specific sequence of A’s, C’s, G’s and T’s in a certain part of the genome. Recall those are the four nucleotides that contain the information in DNA.
That is a VERY important point. Knowing the EXACT sequence of nucleotides in a region of interest is very powerful. It can tell us everything from what gene were looking at to what mutations (and alleles) are present in that gene. It’s hard to overstate the importance of sequencing: Just think about the human genome project. That was one big sequencing project, well actually two, but that’s a different story.
The thing is, that was a very slow and expensive project. Technology has improved immensely in the past ten years, meaning that it is cheaper and cheaper to sequence more and more. The techniques have also changed dramatically, so much so that they’re now called Next Generation Sequencing. Like Star Trek, except Captain Picard is in the Andromeda Galaxy.
That’s where Massive comes in. These new technologies are capable of sequencing so much DNA, all at once, that the results can only be called massive. So much information is produced that molecular geneticists today need to be well versed in programming, or have access to a good programmer, to deal with it all.
And of course that ties into Parallel. It’s massive because it’s parallel. Many, many pieces of DNA are sequenced at the same time.
There are many applications for this kind of technology. For instance researchers can choose to sequence the entire genome of an organism, or specifically select large and interesting regions and then do massively parallel sequencing on just those regions. They can also do lots of sequencing on the DNA of many individuals at a time, and then compare them. An appealing way of narrowing down what to look at is by sequencing only mRNA. That works similarly to sequencing DNA, but there you only get regions that are transcribed, which gives you very useful information about which genes are active in the tissue you are looking at, and what mutations/alleles are present.
In the future I’ll feature some articles which use Massively Parallel Sequencing. There are several different technologies that fit under this umbrella term. Understanding the specifics of each technique is often not necessary to understand the general results obtained from a study, although it sure helps. For the lay audience, being familiar with NextGen sequencing will already prove pretty useful.
Image: Christmas w/a K on Flickr
