Essay !1 - Genomics & Omics - Code : KSI0001

< Genomics Essay 1 >

Sangin Kim

 

 Genomics refers to the study of the genome in contrast to genetics which refers to the study of genes and their roles in inheritance. Genomics can be considered a discipline in genetics. It applies recombinant DNA, DNA sequencing methods, and bioinformatics to sequence, assemble, and analyze the function and structure of genomes. The field includes efforts to determine the entire DNA sequence of organisms and fine-scale genetic mapping. The field also includes studies of intragenomic phenomena such as heterosis, epistasis, pleiotropy or other interactions between loci and alleles within the genome. It is the new science that deals with the discovery and noting of all the sequences in the entire genome of a particular organism. The genome can be defined as the complete set of genes inside a cell. Genomics, is, therefore, the study of the genetic make-up of organisms.

 Determining the genomic sequence, however, is only the beginning of genomics. Once this is done, the genomic sequence is used to study the function of the numerous genes to compare the genes in one organism with those of another (comparative genomics), or to generate the 3-D structure of one or more proteins from each protein family, thus offering clues to their function. In crop agriculture, the main purpose of the application of genomics is to gain a better understanding of the whole genome of plants. Agronomically important genes may be identified and targeted to produce more nutritious and safe food while at the same time preserving the environment. Genomics is an entry point for looking at the other ‘omics’ sciences.

 The information in the genes of an organism, its genotype, is largely responsible for the final physical makeup of the organism, referred to as the “phenotype”. However, the environment also has some influence on the phenotype. DNA in the genome is only one aspect of the complex mechanism that keeps an organism running – so decoding the DNA is one step towards understanding the process. However, by itself, it does not specify everything that happens within the organism. The basic flow of genetic information in a cell is as follows. The DNA is transcribed or copied into a form known as “RNA”. The complete set of RNA (also known as its transcriptome) is subject to some editing (cutting and pasting) to become messenger-RNA, which carries information to the ribosome, the protein factory of the cell, which then translates the message into protein.

 omics informally refers to a field of study in biology ending in -omics, such as genomics, proteomics or metabolomics. It reflects the change in orientation towards the quantitative analysis of complete or near-complete assortment of all the constituents of a system. Functional genomics aims at identifying the functions of as many genes as possible of a given organism.  It combines different -omics techniques such as transcriptomics and proteomics with saturated mutant collections.

Many “omes” beyond the original genome have become useful and have been widely adopted by research scientists. Proteomics has become well-established as a term for studying proteins at a large scale.

 

Proteomics

Proteins are responsible for an endless number of tasks within the cell. The complete set of proteins in a cell can be referred to as its proteome and the study of protein structure and function and what every protein in the cell is doing is known as proteomics. The proteome is highly dynamic and it changes from time to time in response to different environmental stimuli. The goal of proteomics is to understand how the structure and function of proteins allow them to do what they do, what they interact with, and how they contribute to life processes.

An application of proteomics is known as protein “expression profiling” where proteins are identified at a certain time in an organism as a result of the expression to a stimulus. Proteomics can also be used to develop a protein-network map where interaction among proteins can be determined for a particular living system.

Proteomics can also be applied to map protein modification to determine the difference between a wild type and a genetically modified organism. It is also used to study protein-protein interactions involved in plant defense reactions

 

 

Metabolomics

Metabolomics is one of the newest ‘omics’ sciences. The metabolome refers to the complete set of low molecular weight compounds in a sample. These compounds are the substrates and by-products of enzymatic reactions and have a direct effect on the phenotype of the cell. Thus, metabolomics aims at determining a sample’s profile of these compounds at a specified time under specific environmental conditions.

Genomics and proteomics have provided extensive information regarding the genotype but convey limited information about phenotype. Low molecular weight compounds are the closest link to phenotype.

Metabolomics can be used to determine differences between the levels of thousands of molecules between a healthy and diseased plant. The technology can also be used to determine the nutritional difference between traditional and genetically modified crops, and in identifying plant defense metabolites.

 

 

References

1. https://en.wikipedia.org/wiki/Genomics

2. https://en.wikipedia.org/wiki/Omics

3. http://www.isaaa.org/resources/publications/pocketk/15/default.asp

4. http://geneticscertificate.stanford.edu/courses/genomics-and-the-other-omics