Next-generation sequencing (NGS) has become popular in the last five years. NGS is popular in research work. In clinical work, the leading usage of NGS is for cancer testing.
What is Sequencing?
Sequencing technologies are a way to detect genetic alterations in an individual. These genetic alterations can be mutations, insertions/deletions, rearranagements (also called translocations), amplifications, and expressions. The purpose of sequencing for clinical work is to help decide on treatment. Read more on types of cancer treatment.
What are the types of Sequencing?
There are many types of sequencing. One such example is Sanger sequencing. Each sequencing method has it’s own pros and cons from both a scientific and economic factor.
What is Next-Generation Sequencing?
Next-generation sequencing also called NGS and High-Throughput Sequencing is one of the most recent breakthrough technologies which offers many advantages over older sequencing technologies. Companies that offer next-generation sequencing machines include Illumina (currently the global market leader) and Thermofisher. Just as each sequencing technology has pros and cons each machine and each company also has their own pros and cons.
What are Advantages of Next-Generation Sequencing?
The biggest advantage of NGS is the ability to test hundreds or even thousands of genes at once. Other technologies are only able to test one gene at a time, making repeating the test hundreds or thousands of times unfeasible from a sample quantity and economic perspective. NGS testing for cancer treatment has become very popular and will continue to grow for the foreseeable future. The other advantage is NGS unlike other technology platforms can test for many kinds of alterations at once. In cancer as guidelines recommend an ever-increasing number of gene tests NGS will very likely soon become more cost-effective than other traditional sequencing methods. Certain tests like tumor mutation burden for immunotherapy and liquid biopsy are best performed (or only performed) on NGS.
What are Disadvantages of Next-Generation Sequencing?
The biggest drawbacks are the price and turnaround time. The price per gene tested is far cheaper than other sequencing methods but the overall price a patient has to be per test is more. The other drawback for clinical use is the turnaround time. Due to many samples being required to be pooled to run a NGS machine and the run duration of the machine itself. Therefore, patients and doctors are required to plan ahead and count usually four weeks for results to be delivered.
How accurate is Next-Generation Sequencing?
The general consensus globally is Next-Generation sequencing is accurate enough to perform clinical work. Several companies have US FDA approval for testing on NGS. Several international guidelines are recommending NGS based testing.