Metabolomics

Abstract

Metabolomics is formally defined as the high-throughput study of metabolites which serve as an integral part of the metabolism. With the advent of Human Genome Project, a plethora of data repositories have evolved generating huge amounts of 'omics' data. These data can be classified as genomics, proteomics, transcriptomics and metabolomics. However, amongst these metabolomics directly emulates the biochemical activity of the organism and thus best describes the molecular phenotype. The metabolome of an organism is complex and dynamic as the metabolites are getting continuously absorbed and degraded. Metabolomics studies attempt to provide a comprehensive snapshot of the physiological state of an organism at a given time state. Broadly, metabolomics study can be performed using two approaches: targeted and untargeted approach. In the case of untargeted approach, a number of different metabolites are measured without any sample bias, whereas, in the case of targeted approach, defined sets of metabolites are measured with an objective of the problem to be addressed. However, the steps in both these approaches are common. The first step is to outline the study design where the number of factors is taken into consideration like the sample size, randomisation, etc. This step is done to ensure that all important factors are considered addressing the metabolites involved and their putative interactions. The second step is the preparation of the sample, where the collection, storage and preparation of the sample take place. In the third step, an analytical technique like mass spectroscopy or NMR is utilised to measure and quantify the metabolites. The fourth step is to preprocess the data for analysis in order to extract biological inferences. This step is crucial to avoid noise in the data and perform background correction. The final step would be data analysis. This step includes applying statistical inferences to the data and clustering the data. The aim of this step is to perform the categorisation of the sample properties. Once a metabolomics study is completed, it can be subjected to various applications since it is an approach that is most proximal to capture the phenotype of an individual. This makes it an invaluable tool for pharmaceutics and healthcare. Advanced areas like personalised medicine utilise the metabolomics study for medical diagnosis and prognosis useful for the identification of the disease. Metabolomics is useful as it has the capability of identification and characterisation of different metabolites, making us understand the disease mechanisms in a better way.