Although it is an important technology for studying genomes, DNA sequencing was initially accomplished in 1977 by Frederick Sanger.
Since its conception, the technology has developed rapidly. Alvaro G. Hernandez, director of DNA services at the Roy J. Carver Biotechnology Center, explained that this growth began with the initial assembly of the human genome, known as the Human Genome Project.
“Sequencing and assembling the human genome took 10 years, at a cost of over $3 billion,” Hernandez said. “What happens today is that we can do the same thing, but instead of 10 years, we can do it in five days, and instead of $3 billion, it will cost $3,000.”
DNA is composed of molecules classified by differences in certain structural components called bases. These are known as adenine, thymine, cytosine and guanine. The specific order and number of these bases determine almost every cellular function within an individual, making DNA sequencing vital to understanding how any organism survives.
DNA sequencing refers to reading out these bases so they can be further analyzed to discover each gene’s purpose. Hunter Cobbley, graduate student studying microbiology, explained that this remains a vital step in research.
Get The Daily Illini in your inbox!
“Without DNA sequencing, I think we would be extremely limited in what we could do,” Cobbley said. “DNA sequencing definitely makes things a lot more efficient.”
Although the sequencing developed by Sanger remains a gold standard for safe and efficient sequences, modern genomics needs to view entire genomes, which can be trillions of bases long. Sanger sequencing is better suited for only 300 bases at a time.
The technology used to sequence genetic code has matched this demand, evolving at a breakneck pace. The second, or next, generation of sequencing allowed for thousands of fragments called short reads to be analyzed, which can then be pieced together to recreate a genome.
“Short reads are perfectly fine because all you do is you align them to the reference genome,” Hernandez said. “I would say 90% of the work we do right now is with short reads.”
The latest generation uses longer fragments for easier assembly, and new technologies are actively being developed to increase the accuracy of these genomes.
As a school at the forefront of genomic research, the University requires the latest DNA sequencing machines whenever they are released. Whenever a new machine arrives on campus, the DNA Services Lab sees more requests from innovative researchers ready to explore its possibilities.
“That’s one thing about us, is that we always have the latest instrument,” Hernandez said. “Because if you don’t have it, you go from being the best to being nobody.”
But even with the latest instruments, the DNA Services Lab faces challenges in taking raw samples to raw data.
The lab receives samples from various labs, University and private, and needs to process the samples into short reads that can be read by its machines. This includes breaking apart the DNA into fragments and adding the adaptors and barcodes necessary for attaching and identifying the DNA after it gets processed.
“Our strength here is that we get all sorts of samples: good samples, degraded samples, samples with a lot of DNA, samples with little DNA,” Hernandez said. “Now, we have to make everything work.”
Even with these challenges, the lab can grow because of an important ideal: collaboration. The members of the DNA Services Lab are efficient in processing DNA, allowing for a fast turnaround in returning data to labs that need it.
Cooperation continues outside the lab as well — companies developing new machines often test their products at the University, and Hernandez and the sequencing facilities learn about upcoming technology they can prepare to buy.
“What we have with the companies is not just some relationship,” Hernandez said. “We have a very strong partnership because their success is our success.”
The technology required to sequence DNA remains complex, so these partnerships are vital to the University’s success in genomics. Researchers have continued to feel their positive impacts.
“Sequencing is such a complex process when you’re first getting into it,” Cobbley said. “Over my time here, things have just become a lot more collaborative.”
