Mutations of genetic codes

The order of nucleotides in deoxyribonucleic acid and ribonucleic acid determines the amino acid order of proteins. Despite the fact that the linear sequence of nucleotides in DNA provides the information for protein sequences, some mutations can have a significant impact on amino acid coding, which can in turn affect what proteins are produced, which can have a significant impact on cellular and organismal function, as mutations of genetic codes are really important for the evolution.

Mutations of genetic codes-

Now we will look at the meaning of genetic code, mutation, how to change genetic code and lastly at mutation and genetic code notes.

Genetic code-

The genetic code is a collection of laws that define how DNA’s four-letter code is translated into amino acids’ 20-letter code, which serves as the building blocks of proteins. The genetic code is made up of codons, which are three-letter nucleotide pairings that each correspond to a distinct amino acid or stop signal. Francis Crick and his colleagues initially proposed the notion of codons in 1961.

It consists of a set of rules through which living cells convert genetic information (DNA or RNA sequences) into proteins (amino acid sequences).

Each triplet of nucleotides in a nucleic acid sequence indicates a single amino acid, as shown in the code.

Despite the fact that there are various different codes, the canonical or standard genetic code, or simply the genetic code, is generally referred to as such since the vast majority of genes are encoded with exactly the same code; however, the canonical genetic code is not universal. In humans, for example, protein synthesis is based on a genetic code that varies from the canonical code.

Mutation-

When a DNA gene is destroyed or altered in such a manner that the genetic message carried by that gene is altered, it is called a mutation. A mutagen is a chemical that may cause a permanent change in the physical makeup of a DNA gene, resulting in a change in the genetic information.

How to change genetic code-

Genome editing (also known as gene editing) refers to a set of technologies that allows to alter an organism’s DNA. These technologies allow for the addition, removal, or modification of genetic material at specific points in the genome. 

There have been many ways genome editing developed. CRISPR-Cas9, which stands for clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9, is one of the most well-known for mutations of genetic codes. Because it is quicker, cheaper, more precise, more effective than existing genome editing technologies, the CRISPR-Cas9 system has sparked a lot of interest in the scientific community.

 How does this mutation technique work- CRISPR-Cas9 is a natural genome changing mechanism that bacteria utilise to defend themselves. When bacteria are infected with viruses, they grab tiny fragments of the virus’s DNA and insert them into their own DNA in a specific way to form CRISPR arrays. Bacteria can “remember” viruses thanks to CRISPR arrays (or closely related ones). If the viruses resurface, the bacteria create RNA segments from CRISPR arrays that detect and bind to particular sections of the viruses’ DNA. The bacteria then employ Cas9 or a similar enzyme to rip the virus’s DNA apart, rendering it inoperable.

Mutation and genetic code notes-

Mutation types- Somatic mutations and germ-line mutations are the two primary kinds of mutations depending on where they arise. Non-reproductive cells are where somatic mutations occur. Because genetically normal body cells can compensate for the mutant cells, many types of somatic mutations have no noticeable impact on an organism. 

Other mutations, on the other hand, may have a significant influence on an organism’s existence and function. Many types of cancer are caused by somatic mutations that influence cell division (especially those that enable cells to divide uncontrolled).

 Germ-line mutations may develop in gametes or cells that will generate gametes in the future. Germ-line mutations, unlike somatic mutations, are handed down across generations. As a consequence, all cells in future generations of organisms will carry the mutation (both somatic and germ-line).

Genetic code- There are two forms of genetic coding. RNA codons or DNA codons may be used to express the genetic code. RNA codons are the codons that are actually “read” during the synthesis of polypeptides and are found in messenger RNA (mRNA) (the process called translation).

The genetic code is universal, which means it can be found in all living things on the planet. The amino acid that a triplet produces in one creature is the same amino acid that it produces in all other species.

 The genetic code follows the redundancy method, which states that distinct codons may generate the same amino acid but that a single codon cannot participate in the production of multiple amino acids. However, depending on where the start codon is located, a sequence may be interpreted in a variety of ways.

Conclusion-

We learned about the genetic code, its traits, mutations. Based on this, we can conclude that the genetic code is a set of rules that determine the linear sequence of a polypeptide derived from a linear sequence of nucleotides. That is, they determine how the nucleotide sequence of an mRNA is translated into the amino acid sequence of a polypeptide.

It is the relationship between the nucleotide sequence of mRNA and the amino acid sequence of the polypeptide. Mutation is also crucial as mutations of genetic codes in the initial stage in evolution since it results in the creation of a new DNA sequence for a specific gene, resulting in a new allele. Intragenic recombination may also result in the creation of a new DNA sequence (a new allele) for a certain gene.