A Guide to Understanding How Next Generation Sequencing Works
Next Generation Sequencing is an important tool in the study of DNA. It has revolutionized how we can understand our genes and will be a big part of finding cures for diseases like cancer. However, it’s not always easy to fully understand exactly how this technology works. We are going to go through all the basics you need to know about Next Generation Sequencing so that you have a better understanding.
Prepare the DNA Sample
In order to read a DNA strand, the DNA must be cut into smaller pieces using a restriction enzyme. The DNA will then need to go through a process called amplification in order to ensure that there is enough DNA present for the technician to work with later on. This generally relies on PCR (polymerase chain reaction) which allows scientists to amplify only the DNA needed for sequencing.
Preparing Sequencing Sample
For each of these samples, you need to know how much DNA is in there and the size of the DNA pieces (chromosomes). This can be done using a technique like qPCR (quantitative PCR). After this step, you want to add on a piece of DNA called a sequencing primer. This is the scaffold that the DNA will be added onto later, and it helps to have some extra nucleotides.
Next, you will mix in a special enzyme pair called a polymerase and dNTPs (dATP, dCTP, dGTP, and dTTP). Then add in the sequencing chemicals. This mixture is called a sequencing reaction. Next, you will place the samples in a machine to perform the reactions (just like making an Alton Brown recipe)
Sequencing Reaction
This sequencing reaction will go through a process called electrophoresis. In this step, an electrical current is applied to the samples, which forces the DNA fragments to move through a gel towards the positive charge. This makes it easier for scientists to visualize and read the DNA sequence later in their free time or when needed.
Preparing Sequencing Data
To analyze and read the data from this sequencing reaction, scientists will use a method called chemiluminescence. Basically, they add chemicals and expose the samples to light which makes the DNA fragments glow. This allows for easy visualization of where each nucleotide is on the sequence to be recorded and analyzed.
Analysis and Readout of Sequencing Data
After the data has been analyzed, you will have a graph of where all these nucleotides are. You can use this information to determine what genes are in your DNA! Furthermore, scientists can use Next Generation Sequencing to look at other aspects of the genome, including epigenomics (the study of changes in gene expression), transcriptomics (the study of gene expression), and proteomics (the study of proteins).
In the end, sequencing is a simple yet powerful process that allows us to understand our DNA better. It’s also important for scientists to know how these sequencing reactions work to troubleshoot problems when they come up!
With the power of Next Generation Sequencing, scientists can now look at individual DNA strands to better understand what makes us unique. This has opened up study in many different fields and will continue to be important as we try to find cures for diseases like cancer!