Description: Sanger sequencing is a fundamental method in molecular biology for determining the nucleotide sequence in a DNA strand. This process is based on the incorporation of nucleotides labeled with a fluorescent or radioactive dye, which act as chain termination inhibitors. By adding these modified nucleotides, DNA fragments of varying lengths are generated that terminate in a labeled nucleotide. These fragments are then separated by size using gel electrophoresis, allowing for the visualization of the sequences. This method is highly accurate and has been a cornerstone in genomics, as it allows for the reading of DNA sequences with high fidelity. Sanger sequencing is particularly valuable in identifying genetic mutations and characterizing genes, making it an essential tool in biomedical research and the diagnosis of genetic diseases. Its ability to provide detailed information about the structure of DNA has facilitated significant advances in the understanding of genetics and molecular biology.
History: Sanger sequencing was developed by Frederick Sanger and his team in 1977. This method revolutionized molecular biology by allowing precise DNA sequencing. Sanger received his second Nobel Prize in Chemistry in 1980 for this work, which laid the groundwork for the development of more advanced sequencing techniques. Over the years, Sanger sequencing has evolved, integrating with automated technologies that have increased its efficiency and analytical capacity.
Uses: Sanger sequencing is used in various applications, including the identification of genetic mutations, gene cloning, and sequence verification in larger sequencing projects. It is also fundamental in the research of hereditary diseases and the development of gene therapies. Additionally, it is employed in the characterization of microorganisms and in studies of genetic biodiversity.
Examples: A practical example of Sanger sequencing is its use in the Human Genome Project, where it was used to sequence specific regions of human DNA. Another case is the identification of mutations in the BRCA1 gene, which are associated with an increased risk of breast cancer. It is also used in clinical laboratories to confirm genetic diagnoses.
