The term “Systems Biology” is being using with increasing incidence in the scientific literature. However, a review of the papers published with the keyword “systems biology” quickly demonstrates that this discipline is quite broad and that the exact definition of a “systems biology approach” is unclear. Systems biology can be defined as “the study of an organism, viewed as an integrated and interacting network of genes, proteins and biochemical reactions which give rise to life”. The key distinction in a systems biology approach to research is that instead of analyzing individual components or aspects of an organism, such as lipids or a specific gene/protein, the focus is placed on examining how all of the components interact as a single system. It is thought that by focusing on the entire organism as a single unit that biological mechanisms can be elucidated. The above figure taken from Ahn et al. (2006) demonstrates this point in that systems biology focuses on the relationships between components and not necessarily the components themselves. For example, the disease atherosclerosis exhibits a complex development that involves multiple components of the inflammatory cascade as well as the immune system. Accordingly, it is difficult to attribute any one specific marker (i.e., metabolite, gene or protein) with risk for disease. Instead, by examining the system as a whole and exploring multiple pathways simultaneously, a greater indication of organism state and current phenotype can be acquired. This knowledge can in turn be applied to develop therapeutic interventions and treatment strategies that address the overall imbalance (e.g. shift from equlibrium) in the system.

Systems biology emerged out of the Human Genome Project, which provided the initial impetus to think of science in terms of large-scale systemic datasets. The commensurate increase in our ability to acquire data via the technologies in the "omics-cascade" has greatly enhanced our ability to probe biological mechanisms. The science of systems biology has been greatly facilitated and convergently evolved with increased access to the internet, on-line databases, data storage facilities and computing power. Of particular interest is the development that systems biology is truly interdisciplinary in that no single discipline can lay claim to being “systems biology”. Instead, it is a conglomeration of biologists, chemists, statisticians, computer scientists, mathematicians, physicists, and engineers, among others. Systems biology studies are providing the research community with a growing understanding of how transcribed genes and their resulting translated proteins give rise to a suite of metabolites that determine biological form and function. In a sense, systems biology can be considered to be an investigation into the factors that determine the phenotype of the organism, which is often the endpoint of most interst, at least in a clinical setting.