Introduction to NGS

Learn how the technology works and what it can do for you

Next-Generation Sequencing (NGS)

Next-generation sequencing (NGS) 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. NGS has revolutionized the biological sciences, allowing labs to perform a wide variety of applications and study biological systems at a level never before possible.  

Today's complex genomics questions demand a depth of information beyond the capacity of traditional DNA sequencing technologies. NGS has filled that gap and become an everyday tool to address these questions.

New-to-NGS Scientist in Lab
Next-Generation Sequencing for Beginners

We'll guide you through the basics of NGS, with tutorials and tips for planning your first experiment.

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Next-generation sequencing technology has fundamentally changed the kinds of questions scientists can ask and answer. Innovative sample preparation and data analysis options enable a broad range of applications. For example, NGS allows labs to:

  • Rapidly sequence whole genomes
  • Deeply sequence target regions
  • Utilize RNA sequencing (RNA-Seq) to discover novel RNA variants and splice sites, or quantify mRNAs for gene expression analysis
  • Analyze epigenetic factors such as genome-wide DNA methylation and DNA-protein interactions
  • Sequence cancer samples to study rare somatic variants, tumor subclones, and more
  • Study the human microbiome
  • Identify novel pathogens

Explore Sequencing Methods & Uses

Using capillary electrophoresis-based Sanger sequencing, the Human Genome Project took over 10 years and cost nearly $3 billion.

Next-generation sequencing, in contrast, makes large-scale whole-genome sequencing (WGS) accessible and practical for the average researcher. It enables scientists to analyze the entire human genome in a single sequencing experiment, or sequence thousands to tens of thousands of genomes in one year.

Learn More About WGS

NGS Data Analysis Tools

Explore user-friendly tools designed to make data analysis accessible to any scientist, regardless of bioinformatics experience.

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Broad Dynamic Range for Expression Profiling

NGS-based RNA-Seq is a powerful method that enables researchers to break through the inefficiency and expense of legacy technologies such as microarrays. Microarray gene expression measurement is limited by noise at the low end and signal saturation at the high end.

In contrast, next-gen sequencing quantifies discrete, digital sequencing read counts, offering a broader dynamic range.1,2,3

Compare Arrays vs. RNA-Seq

Tunable Resolution for Targeted NGS

Targeted sequencing allows you to sequence a subset of genes or specific genomic regions of interest, efficiently and cost-effectively focusing the power of NGS. NGS is highly scalable, allowing you to tune the level of resolution to meet experimental needs. Choose whether to do a shallow scan across multiple samples, or sequence at greater depth with fewer samples to find rare variants in a given region.

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Illumina NGS technology utilizes a fundamentally different approach from the classic Sanger chain-termination method. It leverages sequencing by synthesis (SBS) technology – tracking the addition of labeled nucleotides as the DNA chain is copied – in a massively parallel fashion.

Next-generation sequencing generates masses of DNA sequencing data, and is both less expensive and less time-consuming than traditional Sanger sequencing.2 Illumina sequencing systems can deliver data output ranging from 300 kilobases up to multiple terabases in a single run, depending on instrument type and configuration.

Learn More About SBS Technology

Labeled Nucleotide Addition During SBS

Recent Illumina next-generation sequencing technology breakthroughs include:

  • Semiconductor sequencing: The iSeq 100 System combines a complementary metal-oxide semiconductor (CMOS) chip with one-channel SBS to deliver high-accuracy data in a compact system.
  • Patterned flow cell technology: This option offers an exceptional level of throughput for diverse sequencing applications.
  • Up to 6 terabases (Tb): Learn how the NovaSeq 6000 System offers tunable output of up to 6 Tb in ~2 days.
  • 75 breakthrough innovations: The NextSeq 1000 and 2000 Systems offer flexibility for emerging applications, our simplest workflow yet, and data analysis in as little as 2 hours.   
Precision Health

Personalized medicine programs can help match patients to treatments based on their genetic blueprints and improve survival rates, quality of life, and the cost of care.

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In-Depth NGS Introduction Introduction

In-Depth NGS Introduction

This detailed overview of Illumina sequencing describes the evolution of genomic science, major advances in sequencing technology, key methods, the basics of Illumina sequencing chemistry, and more.

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Genetics of COVID-19 Susceptibility

This UK-wide study uses NGS to compare the genomes of severely and mildly ill COVID-19 patients, to help uncover genetic factors associated with susceptibility.

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Exploring the Tumor Microenvironment

Scientists use single-cell NGS techniques to study cancer microenvironments, elucidate gene expression patterns, and gain insights into drug resistance and metastasis.

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Cell-Free RNA as a Noninvasive Biomarker

This research highlights the broad potential of circulating cell-free RNA sequencing for biomarker discovery and noninvasive health monitoring.

Read Article

The resources below offer valuable guidance to scientists who are considering purchasing a next-generation sequencing system.

Download Buyer’s Guide

NGS Experimental Considerations

Learn about read length, coverage, quality scores, and other experimental considerations to help you plan your sequencing run.

Use our interactive tools to help you create a custom NGS protocol or select the right products and methods for your project.

Start Planning Experiments

NGS for COVID-19

Next-generation sequencing is uniquely positioned in an infectious disease surveillance and outbreak model. Learn which NGS methods are recommended for detecting and characterizing SARS-CoV-2 and other respiratory pathogens, tracking transmission, studying co-infection, and investigating viral evolution. 

Explore Coronavirus NGS Methods
COVID-19 Solutions
Methods Guide

Access the information you need—from BeadChips to library preparation for genome, transcriptome, or epigenome studies to sequencer selection, analysis, and support—all in one place. Select the best tools for your lab with our comprehensive guide designed specifically for research applications.

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Methods Guide
Fighting drug-resistant tuberculosis in South Africa
Fighting drug-resistant tuberculosis in South Africa

Experts agree that next-generation sequencing is the best weapon for comprehensively tracking multi-drug-resistant TB

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Using Analytics to Improve Cancer Diagnosis and Therapy Selection
Using Analytics to Improve Cancer Diagnosis and Therapy Selection

Developing and automating workflows for analyzing, processing, and sharing genomic data among researchers and clinicians.

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Children’s Mercy Kansas City tackles the unique complexity of pediatric cancer
Children’s Mercy Kansas City tackles the unique complexity of pediatric cancer

A new exome-based test will help determine the genetic variants—germline and somatic—driving these rare cancers

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  1. Wang Z, Gerstein M, Snyder M. RNA-Seq: a revolutionary tool for transcriptomics. Nat Rev Genet. 2009;10:57–63.
  2. Wilhelm BT, Landry JR. RNA-Seq—quantitative measurement of expression through massively parallel RNA sequencing. Methods. 2009;48:249–57.
  3. Zhao S, Fung-Leung WP, Bittner A, and Ngo K, Liu X. Comparison of RNA-Seq and microarray in transcriptome profiling of activated T cells. PLoS One. 2014;16;9(1):e78644