Deoxyribonucleicacid or the DNA is the inherited material in roughly all organismsincluding human beings (Robin et al., 2015).Virtually all cells inthe body of an individual contains similar DNA. Mainly it is situatedin the nucleus of the cell, and it referred as nuclear DNA. However,mitochondria also include the little quantity of DNA and it is knownas mitochondrial DNA. The aim of this paper is to explain how thefour-letter code of DNA is changed to twenty letter code of proteins.
Aset of rules known as the genetic code is used to describe how theDNA code of four letters is transformed to the proteins code oftwenty letters (Robin et al., 2015). The proteins systems are made ofamino acids. The system of genetic is a combination of three-letterof nucleotides named codons. Each one of these codons stops a signalor match to a particular amino acid. Crick Francis together with hiscolleagues backs in 1961were the first to describe the notion ofcodons. Also, Heinrich Matthaei and Marshall Nirenberg in the sameyear carried out the experiments that started to decipher the code ofgenetic (Robin et al., 2015). They demonstrated that the sequence ofUUU of the RNA specifically coded for the phenylalanine of the aminoacids. After this finding, Khorana Gobind, Philip, and Nirenbergrecognized the remaining genetic code as well as describing every3-letter codon to its matching amino acid.
Thereare sixty-four possible combinations or permutations of thenucleotide of three-letter successions that can be formed from thenucleotides. Three out of the total codons denote stop signals whilesixty-one embody amino acids (Robin et al., 2015). It is noted thatseveral codons can code one amino acid despite the notion that eachcode is for a particular stop signal or amino acid. Thus, due to thismulti-coding behavior of codons, the genetic code is always depictedas redundant or degenerated. Further, it is pointed that there is nooverlapping in genetic code thus, signifying that a single nucleotideonly belongs to one codon and alone nucleotide cannot be the piece oftwo adjacent codons. Moreover, genetic code has rare cases ofvariation, and thus it is almost universal. For instance,mitochondria can have a genetic code with small deviations (Robin etal., 2015).
Inconclusion, the DNA is the natural material in roughly all organismsincluding human beings. The genetic code is used to describe how theDNA code of four letters is transformed to the proteins code oftwenty letters.The code of genetic is a combination of three-letterof nucleotides named codons. There are sixty-four possiblecombinations or permutations of the nucleotide of three-lettersuccessions that can be formed from the nucleotides. The genetic codeis always depicted as degenerated, un-overlapping with rare variationcases.
Robin,S., Rodolphe, F., & Schbath, S. (2015). DNA,words and models.Cambridge, UK: Cambridge University Press.