Thirteen years and $2.7 billion. That’s what it took researchers involved in the Human Genome Project to sequence, or identify, the human genome the first time, using a DNA sequencing method invented in 1975 by two-time Nobel laureate, Frederick Sanger. This enabled scientists to finally determine the order of nucleotides—represented by the letters A, C, T, and G—that make up DNA. It’s the sequence of these letters that helps determine the traits of an organism, healthy or otherwise.
There are 3 billion chemical base pairs that make up the DNA double helix at the center of every cell. Intermingled through the DNA are 20,000 to 25,000 genes. The complete set is known as the genome and it’s this incredible recipe book that tells the body how to make proteins, heart cells, brain matter, muscle, and bone. A wrong letter hidden deep inside a gene can boost the risk of developing breast or prostate cancer, begin to damage the delicate endothelial cells that line blood vessels, or start the cellular destruction in the brain that eventually leads to dementia decades later.
The Human Genome Project has set doctors, computer scientists, biologists, physicists, chemists, and engineers on a path to find the genetic errors that trigger disease. In parallel, this search has helped foster the creation of newer, faster, and less expensive methods of gene sequencing. The pace of technological innovation has been dizzying over the past decade, with the cost of sequencing a human genome dropping by a factor of more than 10,000. And while the machines used in the Human Genome Project read 25,000 bases a week in 1990 and 5 million in 2000, the next-generation gene sequencers being used now can read 250 billion bases in a week.
Next-generation sequencing technology continues to improve at an extraordinary rate, with new warp-speed sequencers now making it feasible for researchers to conduct experiments once considered too expensive or just simply impossible.
The best way to get to the root cause of serious illness is to sequence a person’s genome. Leading geneticists envision a day soon when everyone's genome will be sequenced and included as a routine part of their medical records. Next-generation sequencing machines can help achieve this goal in the near future with the wider dissemination of faster and affordable sequencing machines.
One of today’s new silicon-based machines is small—about the size of a tabletop printer—and inexpensive at $50,000. Even so, it’s capable of reading 10 million letters of genetic code in just two hours. For the first time, every scientist, local hospital, and college will be able to afford one.
Using other, more powerful sequencers that are now available, a human genome can be read in eight days at a cost of $10,000. It’s expected that in a few years, the next-generation sequencing machines will be able to map a human genome in 15 minutes, all for $1,000 or less.
Not only is this increase in speed and cost reductions in the next-generation gene sequencers turning biology upside down, but also it is getting us much closer to finally discovering what it truly is to be a human being.
Where Are They Now
The field of next-gen sequencers is expanding rapidly and these devices have become go-to items in the armamentarium of researchers. Pathology laboratories that utilize these silicon-based machines now offer clinicians the ability to detect and characterize disease at earlier stages when a cure is still possible. A benchtop device capable of sequencing the human genome in one day for $1,000 is now available, while a newer palm-size device that can sequence the genome in 15 minutes became available in 2014. From 2015-2022, the global next generation gene sequencing market is expected to grow by over 40% to reach $27.8 billion. This is mainly due to the lowered turnaround time and reduced costs of the gene sequencing tests, leading to increased adoption of the test for research and clinical use. Unfortunately the miniature device has reported misidentifications in DNA sequence 5-30% of the time – a high error rate compared with those of existing full-sized sequencers.