The entire world of biology and the study of human anatomy changed drastically once we learned about genetics and human DNA. For the past 70 years, researchers and scientists from various fields have been working together to discover the best sequencing methods that could transform our understanding of human evolution. This research has led to the development of cutting-edge methodologies in biological research, which has reduced the time and cost of obtaining biological knowledge.
What do You Understand About DNA and DNA Sequencing?
Humans are 99.9% identical to each other.1 So, what makes us unique? The 0.1% genome is what makes us unique from every other person on Earth. This genetic code determines whether you will have blonde hair or not, the color of your eyes, and whether you have the risk of any heart disease or diabetes inherited from your parents. You might know that DNA, or deoxyribonucleic acid, is the hereditary material found in humans and most other animals walking, flying, or swimming on Earth. A crucial point to know about DNA is that it can replicate itself, and each strand of DNA in the double helix structure can serve as a pattern for duplicating the sequence of bases.
DNA sequencing is the method by which we can define the exact order of the four nucleotide bases⏤adenine, guanine, cytosine, and thymine⏤that make up a strand of DNA. These bases offer the underlying genetic basis (genotype) for instructing a cell what to do, where to go, and how to become a defined kind of cell (phenotype).
The Discovery of DNA Sequencing From the Beginning
The discovery of DNA sequencing can be traced back to the 1970s, when techniques for sequencing ribonucleic acid (RNA) were developed in the 1960s. Let us take a look at the entire journey of DNA sequencing from the beginning:2
- In 1970, Ray Wu, a Chinese-American biologist based at Cornell University, published one of the very first DNA sequencing methods. He used highly labeled deoxynucleotides and DNA polymerase, which he found to sequence the terminal region of a DNA molecule.
- In the late 1970s, Fred Sanger improved Ray Wu’s method of DNA sequencing at the Laboratory of Molecular Biology in Cambridge. He, alongside Alan Coulson, published the “Plus and Minus” technique of DNA sequencing in 1975. After two years, Sanger and his associates came up with the “Sanger method” or “dideoxy sequencing.” This method allows the sequencing of long stretches of DNA at a rapid rate.
Both these methods fall under the first generation sequencing and rely on separating the mixture of DNA fragments of various sizes on polyacrylamide (PAA) slab gels.3 Sanger’s research on DNA sequencing came up with the “chain termination method” that became widely popular and went on to rule the world of sequencing for the next thirty years. He also won the Nobel Prize in 1980 for this revolutionary research and went on to be considered a giant in genomics. But modern times need newer and cost-cutting methods of DNA sequencing. So the research to develop better and simpler methods went on.
- In 1986, for the very first time, an automated DNA sequencer was developed by Leroy Hood and his colleagues at the California Institute of Technology. Hood achieved this with the assistance of a team including Lloyd Smith, Michael, and Tim Hunkapiller. 4
- In the 1990s, various new DNA sequencing machines and methods were developed with great success. These techniques were developed following the introduction of microfluidic separation devices, which improved sample injection and decreased separation times. This increased both the accuracy and efficiency of DNA sequencing.
The Use of Technology in DNA Sequencing and Computational Biology
Nowadays, DNA computing is an advanced branch of computing that uses DNA, molecular biology, and biochemistry hardware to replace the old electronic computing. In 1994, Len Adleman demonstrated a computing application that has now spread across various avenues, like the development of nanoscale imaging modalities, storage technologies, reaction networks, and synthetic controllers. 4
With the innovation in computational biology, biologists use pattern-matching algorithms, mathematical models, image processing, and others to review and derive meaning from the sequencing data. With the advent of next-generation sequencing (NGS), it is the first choice for large-scale genomic and transcriptomic sequencing at lower cost and much faster. 5
The Human Genome Project & Applications of DNA Sequencing in Modern Times
The Human Genome Project, also known as the HGP, is an international collaborative research program to map all the genes of human beings and was launched for the benefit of humanity in the long run. The goal of this 15-year project was to completely decipher the human genome and come up with advancements in the fields of disease treatment and medical science.6
Let us see some of the popular applications of DNA sequencing:7
- In medical science, DNA sequencing is used to identify the genes responsible for any hereditary disorders, largely owing to the Human Genome Project and its research. Sequencing can also help in the detection of new mutations.
- DNA sequencing is widely used in gene mapping to construct maps such as restriction digestion maps, genome maps, and whole chromosome maps.
- Forensic science uses sequencing for criminal identification, individual identification through available hair, nail, blood, or tissue samples, and parental verification.
In recent years, the advent of various DNA sequencing techniques in genetics has had a significant impact on human biology, medicine, and other sciences. With more and more research, scientists and researchers have come up with affordable, accurate, and efficient ways of sequencing DNA for various modern applications that will benefit the entire world.
What are your thoughts on the future of genetics and DNA sequencing? If you enjoyed this blog and would like to read more, go to BYJU’S FutureSchool. Also, please share your thoughts in the section below.
Personal DNA testing and genetic scientists are proving that you’re unique—just like everyone else — Quartz. (n.d.). Retrieved May 4, 2022, from https://qz.com/936525/personal-dna-testing-and-genetic-scientists-are-proving-that-youre-unique-just-like-everyone-else/
A journey through the history of DNA sequencing. (n.d.). Retrieved May 4, 2022, from https://the-dna-universe.com/2020/11/02/a-journey-through-the-history-of-dna-sequencing/
Gùvi}, M., & Gù, M. (2013). THE HISTORY OF DNA SEQUENCING ISTORIJAT SEKVENCIRANJA DNK. J Med Biochem, 32(4), 301–312. https://doi.org/10.2478/jomb-2014-0004
DNA computing | computer science | Britannica. (n.d.). Retrieved May 4, 2022, from https://www.britannica.com/technology/DNA-computing
Kulski, J. K. (2016). Next-Generation Sequencing — An Overview of the History, Tools, and “Omic” Applications. Next Generation Sequencing – Advances, Applications and Challenges. https://doi.org/10.5772/61964
What is the Human Genome Project? (n.d.). Retrieved May 4, 2022, from https://www.genome.gov/human-genome-project/What
Saad, R. (2005). Discovery, development, and current applications of DNA identity testing. Proceedings (Baylor University. Medical Center), 18(2), 130. https://doi.org/10.1080/08998280.2005.11928051