Description: DNA, or deoxyribonucleic acid, is the molecule that carries genetic information in all living organisms and many viruses. Its structure resembles a double helix, composed of two strands of nucleotides that coil around each other. Each nucleotide consists of a phosphate group, a deoxyribose sugar, and one of four nitrogenous bases: adenine (A), thymine (T), cytosine (C), and guanine (G). The sequence of these bases encodes the information necessary for the development, functioning, and reproduction of living beings. DNA is not only fundamental for genetic inheritance but also plays a crucial role in regulating gene expression and protein synthesis. Its study has led to significant advances in fields such as molecular biology, genetics, and medicine, becoming an essential pillar for understanding life at the molecular level. Additionally, DNA is capable of replicating itself, ensuring that genetic information is passed from one generation to the next, allowing for the continuity of species. In summary, DNA is the foundation of modern biology, providing the code that defines the diversity and complexity of life on Earth.
History: DNA was discovered in 1869 by Swiss biochemist Friedrich Miescher, who isolated it from cell nuclei. However, its double helix structure was not described until 1953 by James Watson and Francis Crick, who relied on X-ray diffraction data obtained by Rosalind Franklin. This discovery marked a milestone in molecular biology and opened the door to understanding genetics.
Uses: DNA is used in various applications, including forensic medicine for individual identification, paternity testing, and genetic research to understand hereditary diseases. It is also fundamental in biotechnology, where it is used for drug production and in genetic engineering to create modified organisms.
Examples: A practical example of DNA use is the human genome sequencing technique, which has allowed the identification of genes associated with diseases. Another example is the use of DNA in paternity testing, where a child’s DNA is compared with that of the parents to determine biological relationships.
