Next generation sequencing (NGS) has revolutionized genomic research, unlocking more secrets in DNA and leading to more transformational uses. As next generation DNA sequencing continues to become the norm, the opportunities to improve human health are boundless.
For the past decade, next generation sequencing has helped to deepen our understanding of genetics. What’s more, technology has helped to reduce the costs and accelerate the discovery of sequencing, both of which have added more uses for this groundbreaking technology.
What is Next Generation Sequencing?
Initial DNA sequencing used a process that is now referred to as first generation sequencing or Sanger sequencing and used a chain-termination methodology. Developed by Frederick Sanger in 1977, chain-termination methods were the preferred choice for sequencing from the 1980s to the early 2000s.
The Sanger approach was known for its reliability and simplicity. As technologies advanced, the time and expense necessary began to decrease. Those advances led to the Human Genome Project, a massive undertaking that united scientists the world over and resulted in the first mapping of the human genetic structure. The project, which cost $3 billion and took 13 years, was completed in 2003.
By contrast, NGS uses a very different technique that has provided exponentially more data while lowering costs. Next generation sequencing refers to several similar techniques that allow DNA and RNA to be sequenced far faster than the Sanger approach. Today, NGS is largely an automated process.
Next generation sequencing has several advantages, including:
- Higher reproducibility of results
- The use of far less DNA or RNA material. Nanograms are enough
- Previous knowledge about the genome or genomic features is not necessary
- The process allows for resolution of a single nucleotide, allowing for detection of related genes or features
Applications of Next Generation Sequencing
DNA sequencing has led to significant advances in multiple fields of research but has had fewer applications to medicine. However, the potential is there for more usage to identify and treat illnesses.
NGS does have some limitations that are barriers at present to more applicable use. For one, there is the need for infrastructure – computer storage and analysis capacity. There’s also a need for personnel to analyze, interpret and recommend uses of the data collected.
In addition, the sheer volume of data generated needs to be extracted skillfully.
Despite those limitations, here are some of the potential uses for clinical treatment and public health:
- Clinical Genetics. Modern sequencing far surpasses Sanger in its ability to detect base changes, deletions and insertions of DNA. The technology can be applied to detect novel mutations and genes that cause diseases. For example, NGS can detect mosaic mutations, which are those that develop post-fertilization and present variably in cells and tissues of a person
- Microbiology. Next-generation sequencing can replace standard approaches to identify pathogens, which could provide better clues about drug sensitivities. This sequencing can also identify the interrelationships of pathogens to each other, leading to better sourcing of the infection outbreaks
- Oncology. Next generation sequencing allows for a deeper, more systemic study of cancer genomes, which may provide for more precise diagnoses and classifications, more clear prognoses and potentially more personalized cancer therapies. For example, the technology could be used to identify mutations in tumors that can then be targeted with more effective therapies
- Pandemic Management. NGS has been used to develop kits used for surveillance during the COVID-19 pandemic. These kits provide an important reference genome that can be compared to other viral genomes
The next chapter of next generation sequencing is yet to be written. It is, however, likely to lead to more discoveries and opportunities to better understand the complexities in our DNA.