Before entering fully into the definition of the term genetic code, it is necessary to know the etymological origin of the two words that shape it:
-Code is a word that derives from the Latin "codicus", which in turn emanates from "codex", which were the books that were used to write the rules.
-Genetic, on the other hand, is a term that etymologically derives from Greek. In his case, it emanates from "gennetikos" and means "that originates."
The concept of code It has several uses. In this case we are interested in staying with its meaning as the combination of characters that, within the framework of a certain system, have a certain value.
The genetic , on the other hand, is that linked to biological inheritance and genes: the deoxyribonucleic acid sequence (DNA ) that acts as a functional unit in the transfer of those characters that are inherited.
From these definitions, we can understand what the notion of genetic code . This is the key to the data that houses the genes, which indicates the universal correspondence that exists between the sequence of nucleic acids and the sequence of protein . The genetic code, thus, details how hereditary characters are transmitted .
The rules established by the genetic code allow the translation of a nucleotide sequence (a compound formed by a nitrogen base, phosphoric acid and a sugar ) to one amino acid sequence present in a protein . In this way it specifies the link between sequences of three nucleotides (which are called codons ) and three amino acids. Each codon has a correspondence with a specific amino acid.
The codons, therefore, are sequences of three nucleotides that, in the so-called Messenger RNA , are responsible for coding the aggregate of a certain amino acid in the biosynthesis of proteins. The relationship between codons and amino acids is established by the genetic code.
At RNA , the sequence of the genetic material involves adenine (TO ), the uracil (OR ), the guanine (G ) and the cytokine (C ), while in the DNA the participating nitrogenous bases are adenine (TO ), thymine (T ), the guanine (G ) and the cytokine (C ). These letters that form the codons are those that appear in the genetic code. A codon sequence establishes the characteristics of an amino acid sequence in each protein.
Other data of interest about the genetic code are the following:
-The aforementioned code, as a rule, is represented in a table where the amino acid that is encoded by each codon is identified.
-It has the peculiarity that there can be more than one codon by coding for more than one amino acid. This is what is known as synonyms codons.
-The number of codons is 64: 61 that come to encode amino acids and 3 that do not encode but exert as "stop signals".
-We can also highlight the fact that the genetic code does not present any type of imperfection and also does not have overlaps.
-Numerous are the important figures throughout history who have worked on the genetic code. However, unquestionably the most relevant or those who have left a more relevant legacy are Severo Ochoa, Har Gobind Khorana, Marshall W. Nirenberg and Sydney Brenner as well as Francis Crick, among many others.