Next Generation Sequencing (NGS)

Over the last 56 years, researchers have been developing methods and technologies to assist in the determination of nucleic acid sequences in biological samples. The ability to sequence DNA and RNA accurately has had a great impact in numerous research fields. The sequencing of the human genome was completed in 2003, after 13 years of international collaboration and investment of USD 3 billion.

The Human Genome Project used Sanger sequencing, the principal method of DNA sequencing since its invention in the 1970s. Today, the demand for sequencing is growing exponentially, with large amounts of genomic DNA needing to be analyzed quickly, cheaply, and accurately. Thanks to new sequencing technologies known collectively as Next Generation Sequencing.

Next generation sequencing (NGS), also known as high throughput sequencing or second generation sequencing or short read sequencing, is a massively parallel sequencing technology that offers ultra-high throughput, scalability, and speed. The technology is used to determine the order of nucleotides in entire genomes or targeted regions of DNA or RNA. The main difference between Sanger sequencing and NGS stems from sequencing volume, with NGS allowing the processing of millions of reactions in parallel, resulting in high-throughput, higher sensitivity, speed and reduced cost.

A plethora of genome sequencing projects that took many years with Sanger sequencing methods could now be completed within hours using NGS. There are several main steps that must be tailored to the target (RNA or DNA) and sequencing system selected. The main steps of NGS includes sample preparation (pre-processing), library preparation, PCR amplification, sequencing and data analysis (Post-processing).