DNA sequencing

Article

May 21, 2022

DNA sequencing (English: DNA sequencing) is to determine the binding order (base sequence) of the nucleotides that make up DNA. Since DNA is a molecule that carries almost all of the genetic information of living organisms and is basically encoded in the form of a base sequence, DNA sequencing is a basic means for analyzing genetic information. As a method, the Sanger method developed in 1977 is used with improvements, but recently new methods have been developed and some of them have been put into practical use. Since the information necessary for living organisms is encoded in the base sequence of DNA, sequencing is the basis of micro-level biology, and it is also popular in macro-biology such as taxonomy and ecology. It has been applied to. In terms of medicine, it is also useful for diagnosing genetic diseases and infectious diseases and developing treatment methods. Walter Gilbert and Frederick Sanger were awarded the 1980 Nobel Prize in Chemistry for their development of DNA sequencing techniques. Also called simply sequencing or sequencing.

Application destination

DNA sequencing is used to sequence individual genes, larger gene regions (gene clusters or operons), chromosomes, or the entire genome of an organism. It is also the most efficient method for indirectly examining the base sequences of RNA and proteins via an open reading frame. This technique has become an important technique in many areas of medicine, forensics, anthropology, biology and other sciences.

Molecular biology

In the field of molecular biology, sequencing is used in molecular biology to study the genome and the proteins it produces. Based on the information obtained by sequencing, researchers can clarify the relationship between genetic changes, diseases and phenotypes, and identify drug targets.

Evolutionary biology

In the field of evolutionary biology, DNA sequence information is a substance that transmits information between generations, so it is a clue as to the relationship between different organisms and how they have evolved. In February 2021, it was reported that the oldest organisms were sequenced from mammoths over 1 million years ago.

Metagenomics

Metagenomics identifies organisms present in water, domestic wastewater, sludge and airborne debris, and swab samples taken from organisms. Knowing what organisms exist in a particular environment is essential for research in ecology, epidemiology, microbiology, and other disciplines. Sequencing allows us to investigate what types of microorganisms are present in the microbiome.

Virology

Sequencing is one of the methods for identifying viruses because the virus of interest in virology is too small to be seen under a light microscope. The genome of the virus is composed of DNA or RNA, but RNA virus deteriorates rapidly in clinical samples, so sequencing needs to be done promptly. NGS (next-generation sequencing method), which enables high-speed sequencing, is used for virus base sequence identification in basic research and clinical research, as well as for diagnosis of emerging virus infections, molecular epidemiology of viral pathogens, drug resistance testing, etc. Is also used. More than 2.3 million virus sequences are registered in GenBank. Bird flu outbreak in 1990