Description: Nucleic acids are essential biopolymers for all known forms of life, including DNA and RNA. These complex molecules are composed of chains of nucleotides, which are the basic units containing a phosphate group, a sugar, and a nitrogenous base. Nucleic acids play a crucial role in encoding, storing, and transmitting genetic information. DNA (deoxyribonucleic acid) is responsible for genetic inheritance and is primarily found in the nucleus of cells, where it is organized into structures called chromosomes. On the other hand, RNA (ribonucleic acid) is essential in protein synthesis and acts as an intermediary in gene expression. There are different types of RNA, such as messenger RNA (mRNA), which carries genetic information from DNA to ribosomes, and transfer RNA (tRNA), which assists in translating that information into proteins. The structure of nucleic acids, which includes the famous double helix of DNA, is key to their biological function. Additionally, their ability to replicate and mutate is fundamental to the evolution and adaptation of species. In summary, nucleic acids are vital components of molecular biology, and their study has led to significant advances in fields such as genetics, biotechnology, and medicine.
History: The concept of nucleic acids was introduced by Swiss biochemist Friedrich Miescher in 1869, who isolated a phosphorus-rich substance from cell nuclei, which he called ‘nuclein’. In the following decades, significant advances were made in understanding the structure and function of DNA. In 1953, James Watson and Francis Crick proposed the double helix model of DNA, based on X-ray diffraction data obtained by Rosalind Franklin. This discovery was crucial for understanding how genetic information is stored and transmitted.
Uses: Nucleic acids have multiple applications in biotechnology, medicine, and forensic science. They are used in DNA sequencing techniques, which allow determining the nucleotide sequence in a DNA fragment, facilitating genetic studies and the identification of hereditary diseases. Additionally, they are fundamental in genetic engineering, where they are manipulated to create genetically modified organisms. In medicine, nucleic acids are used in gene therapies and in the development of vaccines, such as mRNA vaccines against COVID-19.
Examples: A practical example of the use of nucleic acids is the PCR (polymerase chain reaction) technique, which allows amplifying specific DNA fragments for analysis. Another example is the use of DNA sequencing in paternity tests, where genetic profiles are compared to determine family relationships. Additionally, mRNA vaccines, such as those from Pfizer and Moderna, use nucleic acids to induce an immune response against the SARS-CoV-2 virus.
