Discovery and Application of Novel Biomarkers

Biomarkers can be divided into three time-based classes: past, present, and future. Past markers are exposure biomarkers and indicate that an exposure has taken place even if there is no adverse consequence from that exposure. Present markers are those that indicate an ongoing process, such as pathophysiology. Future markers are prognostic. They indicate something that is likely to happen but has not yet happened. One of the first applications of the new genomic technologies was in the development of the complex RNA biomarker (transcriptomic biomarker), particularly for distinguishing between various types of cancer that were difficult to differentiate pathologically. There are potentially three forms of DNA alteration that can act as biomarkers of toxicological events. This chapter highlights the many exciting and varied options for the continued development of novel biomarkers that will help to improve the biomonitoring of exposure, effect, and prognosis within humans and human biomaterials.