Introduction

DNA sequencing technologies have undergone significant advancements over the past few decades, transforming the field of genomics research. This research article provides a comprehensive overview of the different DNA sequencing technologies, highlighting their principles, applications, and recent developments. Starting with the Sanger sequencing method, we delve into the era of Next-Generation Sequencing (NGS) platforms and conclude with the emerging technologies that promise faster, more accurate and cost-effective DNA sequencing. Furthermore, we discuss the impact of these advancements on various fields, such as personalized medicine, agricultural genomics, and evolutionary biology. Through this article, we aim to provide researchers and enthusiasts with a comprehensive understanding of the current state of DNA sequencing technologies and their potential implications. DNA sequencing, the process of determining the precise order of nucleotides within a DNA molecule, has revolutionized the field of genomics research. The ability to sequence DNA has paved the way for breakthrough discoveries in various disciplines, including medicine, agriculture, and evolutionary biology. Over the years, DNA sequencing technologies have evolved from the labor-intensive Sanger sequencing method to the highthroughput Next-Generation Sequencing (NGS) platforms. These advancements have not only improved the speed and costeffectiveness of DNA sequencing but have also enabled researchers to explore complex genomic landscapes.

Objectives

The objective of this research article is to provide a comprehensive overview of DNA sequencing technologies, focusing on their principles, applications, and recent developments. By discussing the advantages, limitations, and emerging trends in DNA sequencing, we aim to facilitate a better understanding of the current state of genomics research and its potential implications. Developed by Frederick Sanger in the 1970s, Sanger sequencing relies on the incorporation of chainterminating dideoxynucleotides during DNA replication. This method involves multiple rounds of DNA synthesis, gel electrophoresis, and detection of fluorescently labeled fragments. The resulting sequence is reconstructed based on the pattern of labeled fragments. Sanger sequencing played a crucial role in the Human Genome Project and other early genomic studies. It offers high accuracy and long read lengths. However, it is time-consuming, expensive, and not suitable for large-scale sequencing projects. Sanger sequencing has been instrumental in identifying disease-causing mutations, studying genetic variation, and investigating evolutionary relationships. It continues to be used for targeted sequencing, validation of NGS results, and sequencing of individual genes. NGS platforms, introduced in the mid-2000s, revolutionized DNA sequencing by enabling parallel processing of millions of DNA fragments. These platforms employ a variety of sequencing-by-synthesis approaches, such as reversible terminators, pyrosequencing, and sequencing-by-ligation. NGS enables high-throughput sequencing at reduced cost and time. NGS has accelerated genomics research in diverse fields, including cancer genomics, infectious disease surveillance, metagenomics, and epigenomics. We highlight key studies that have leveraged NGS technologies to gain insights into complex biological processes. Although NGS offers exceptional throughput and costeffectiveness, it is prone to various types of errors, including base-call errors and PCR amplification biases. Additionally, data analysis and storage pose significant challenges due to the vast amount of generated data.

Recent Developments in DNA Sequencing Technologies

Third-generation sequencing technologies, such as Pacific Biosciences (PacBio) and Oxford Nanopore Technologies, have emerged as promising alternatives to NGS. These platforms offer long read lengths, enabling the sequencing of contiguous genomic regions and complex structural variations. Singlemolecule sequencing techniques aim to directly read the DNA sequence without amplification or the need for labeled nucleotides. This approach reduces biases introduced by PCR and provides real-time sequence information. Nanopore sequencing relies on passing DNA through nanopores and measuring the changes in electrical current as nucleotides pass through the pore. This label-free approach offers long reads and has been successfully applied in portable sequencing devices. We discuss the advantages and limitations of third-generation and single-molecule sequencing technologies, including error rates, throughput, and cost. Furthermore, we explore ongoing research and developments aimed at improving the accuracy and scalability of these technologies. DNA sequencing has revolutionized the field of personalized medicine, enabling the identification of disease-causing mutations, prediction of drug responses, and development of targeted therapies. We discuss the applications of DNA sequencing in diagnostics, pharmacogenomics, and disease monitoring. DNA sequencing technologies have greatly advanced agricultural genomics by facilitating crop improvement, plant breeding, and pest management. We explore the applications of DNA sequencing in crop genomics, animal breeding, and microbial communities associated with agriculture. By enabling the comprehensive analysis of environmental DNA, sequencing technologies have revolutionized the field of environmental genomics. We highlight studies that have utilized DNA sequencing to study microbial diversity, track species distributions, and monitor environmental health. DNA sequencing has provided unprecedented insights into evolutionary processes and population genetics.