Targeted Metabolomics: The Next Generation of Clinical Chemistry!

Targeted metabolomics, i.e. the quantitation of predefined sets of endogenous metabolites selected for their relevance in metabolism, has emerged as a new and particularly informative discipline in functional genomics although its roots in diagnosing inborn disorders of metabolism in neonates go back much further than those of genomics or proteomics. Because of its unique capabilities in depicting actual physiological and pathophysiological conditions instead of just predispositions or risk factors, it seems ideally suited for complementing the currently established diagnostic platform technologies (enzyme assays, ion-selective electrodes, immunoassays, and molecular diagnostics) in a synergistic fashion. Of course, both technical and content-related prerequisites have to be met before a new technology can make any inroads in clinical practice and, so, this chapter discusses the development of metabolomics since the early twentieth century, the renaissance of clinical biochemistry in areas like neonatal screening and oncology, the most promising new indications, in which diagnostically relevant metabolic biomarker signatures have been identified and – partly – also validated and, eventually, selected risks and opportunities that have to be kept in mind when trying to promote this area of research and development. Bottom line: there is substantial reason to believe that targeted metabolomics can be the new platform technology in clinical chemistry if the community succeeds in taking advantage of the obvious strengths of this discipline and in avoiding some of the pitfalls that have hindered clinical acceptance for other varieties of functional genomics.