In Next Generation Sequencing (NGS), extremely small DNA fragments can be sequenced. This makes this technique far better than shotgun sequencing.
The various steps of NGS are:
- Small fragments of DNA of the size 2-20 kb are taken.
- The small DNA fragments are annealed onto a slide.
- Then PCR of every fragment is carried. So, every fragment is amplified. The amplified fragments become clearly visible on the slide as a spot.
- Then these spots are converted into single strands.
- Then, the slide is flooded with fluorescently labeled nucleotides and DNA polymerase.
- In the end, Computers are used to scan the fluorescent signals.
The best advantage of high-throughput sequencing is amplicon sequencing. The accuracy of NGS is 99.9%. This technique is extremely fast and cheap; sequencing reactions are completed in very short duration of time.