Approaching biomarker discovery through genomics.

The promise of genomic medicine lies in the ability to identify those factors that modify risk of disease at the individual level and, once identified, to be able to provide a personalized treatment or intervention to ablate the disease process. This concept is based upon a number of assumptions and current limitations that genomic science has yet to address. Critical to the development of personalized medicine is the determination of the genetic and epidemiologic cause of complex human disease, such as coronary heart disease, diabetes, asthma, and stroke. The risk factors that predispose an individual to any one of these disorders may not be unique, and the genomic profiles may be similar. Increasing the complexity of understanding the pathogenesis of these disorders is the growing recognition that the genetic risk factors likely interact not only with each other but also with poorly understood environmental factors. Ultimately, the prediction of an individual's risk for any disorder will be determined by their genotype and their environmental exposures; however, in the absence of a defined genomic fingerprint, a subset of confirmed genetic risk factors can be used to help define biomarkers of disease. Clinically validated biomarkers can then serve as surrogates for the combined effects of genotype and environment and provide insights into disease pathogenesis.