Next Generation Sequencing

Next Generation Sequencing (NGS) or high-throughput sequencing technique, has revolutionized genomics by enabling efficient and cost-effective sequencing of large quantities of genetic material. Unlike the traditional Sanger sequencing method that was commonly used before NGS, next-generation sequencing allows for the simultaneous sequencing of multiple DNA or RNA fragments in a massively parallel manner, generating substantial amounts of sequencing data within a short time frame.

NGS platforms employ diverse techniques but generally involve three main steps: library preparation, sequencing, and data analysis. DNA or RNA samples are fragmented during the library preparation, and adapters are attached to the fragment ends, and the resulting library is amplified to generate sufficient material for sequencing. In the sequencing step, the library is loaded onto a sequencing platform, and millions of fragments are sequenced simultaneously using different methods like fluorescence detection or sequencing-by-synthesis. Finally, the obtained sequencing data undergoes bioinformatics analysis to assemble the fragments, align them to a reference genome, and extract meaningful biological information. NGS can be applied to sequence entire genomes or focus on specific areas of interest.

NGS can be used for whole genome sequencing or sequencing of a particular region of the organism's genome. Next-generation sequencing (NGS) technology can be categorized into two major paradigms: short-read and long-read sequencing. Short-read sequencing provides lower-cost, higher-accuracy data that are particularly valuable for population-level research and clinical variant discovery. In contrast, long-read approaches produce longer read lengths, making them well-suited for de novo genome assembly applications and full-length isoform sequencing.

NGS has many applications in biomedical research, clinical diagnostics, and other fields. It enables the investigation of genetic variations, including single nucleotide polymorphisms (SNPs), insertions, deletions, and structural variations, contributing to our understanding of disease susceptibility, drug response, and genetic diversity. NGS is also utilized to study gene expression patterns, epigenetics, metagenomics, and transcriptomics. Furthermore, NGS has been crucial in advancing personalized medicine and precision oncology, where genetic profiles can guide targeted therapies for individual patients. [Md. Tofazzal Islam]