Journal of Medical Diagnostic Methods
Open Access

DNA Sequencing: A Revolution in Genetics, Medicine and Biotechnology

Sitam Florence^{* *}Correspondence: Sitam Florence, Department of Medical Diagnostic, University of Dalhousie, Nova Scotia, Canada, Email:

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Description

DNA sequencing is one of the most transformative advancements in modern biology and medicine. By determining the exact order of nucleotides in a Deoxyribonucleic Acid (DNA) molecule, scientists can gain insights into genetic information, disease mechanisms, evolutionary patterns, and more. Since its inception in the 1970s, DNA sequencing has evolved from a time-consuming and expensive process to a highthroughput, cost-effective tool used in many scientific fields, including genomics, medicine, and biotechnology. The sequence of these bases encodes genetic information, and the order of these bases dictates the synthesis of proteins that perform critical functions in cells. DNA sequencing is the process of determining this sequence of nucleotides. With an accurate DNA sequence, investigators can study how genes function, how mutations affect health, and how organisms are related to one another. The process generates a mixture of DNA fragments of different lengths, each ending with a nucleotide that corresponds to the base of interest. These fragments can be separated by size using gel electrophoresis, allowing investigators to read the sequence of bases by analyzing the pattern of fragments. The Sanger method was revolutionary in its time and became the foundation for many early sequencing efforts, including the Human Genome Project. NGS is now widely used in various fields, including personalized medicine, cancer study, microbiology, and evolutionary biology. Unlike the Sanger method, NGS does not rely on gel electrophoresis; instead, it uses optical detection systems to capture images of DNA fragments as they are synthesized. This is the most widely used NGS method. It involves synthesizing new DNA strands using fluorescently labeled nucleotides, which are detected as they are incorporated into the growing DNA chain. Illumina sequencing generates high-throughput, accurate sequences, making it ideal for whole-genome sequencing and other large-scale applications. This technology detects changes in electrical conductivity as DNA strands pass through tiny nanopores. Unlike other methods, Oxford Nanopore sequencing does not require amplification of the DNA, allowing for real-time sequencing of long reads. It has applications in field-based sequencing and rapid diagnostics due to its portability. One of the primary uses of DNA sequencing is in the study of genomes. The sequencing of entire genomes of organisms, including humans, has provided invaluable insights into genetic variation, evolution, and the genetic basis of diseases. The Human Genome Project, completed in 2003, mapped the entire human genome, consisting of over three billion base pairs, and identified approximately 20,000 to 25,000 genes. DNA sequencing is at the heart of personalized or precision medicine, which tailors medical treatment based on an individual's genetic makeup. By sequencing a person's genome, doctors can identify genetic variations that may predispose them to certain diseases or influence their response to drugs. This allows for more effective, customized treatment plans, especially in fields like oncology and pharmacogenomics. Sequencing the DNA of cancer cells has provided a deeper understanding of how cancer develops and progresses. It helps identify genetic mutations associated with different cancer types, track cancer evolution over time, and discover new targets for drug development. It also plays a significant role in understanding evolutionary relationships between species, tracing the origins of domesticated animals and plants, and studying biodiversity. DNA sequencing technology continues to evolve at a rapid pace. Future advancements may lead to even faster, cheaper, and more accurate sequencing methods, enabling real-time sequencing of entire genomes in clinical settings. The development of portable sequencers could make DNA sequencing more accessible in remote areas or during outbreaks of infectious diseases. DNA sequencing has fundamentally changed our understanding of biology and opened up countless possibilities in medicine, research, and biotechnology.