269 Chapter 17 BIOMARKERS IN DISEASE DIAGNOSIS AND TREATMENT Integration of Biomarkers to Improve Patient Care Ralf Hoffmann Philips Research, Eindhoven, The Netherlands Abstract: The concept of biomarkers is becoming more relevant in disease diagnosis and prognosis, as well as in pharmaceutical drug development. The particular role of these biomarkers is to improve the early diagnosis of human disorders, to give an individual prognosis of the stage and progression of a diagnosed disease, and to predict and monitor the effectiveness of an applied therapy. In medical compound development, their main impact will be on the prediction of adverse and toxic effects, and clinical efficacy of new chemical entities in man. Keywords: Biomarkers, molecular markers, molecular diagnostics, molecular imaging, therapy, drug development, integration of biomarkers 1. RELEVANCE OF BIOMARKERS In 2001, the Human Genome Consortium presented the first draft of the human genome sequence, and provided a final update of the draft sequence three years later 1,2 . Despite the enormous promise of its clinical relevance, the impact of the human genome sequence in terms of benefit in treating human disorders turned out to be limited, until we better understand how a genome translates into a phenotype and which changes on the molecular level give rise to a pathology on the macroscopic level. Knowledge of the human genome sequence will accelerate the identification of genes, whose function is associated with a human disease. 269-285. © 2006 Springer. Printed in the Netherlands. Several approaches can lead to the discovery of novel human disease genes, e.g., genetic linkage analysis 3 , or expression profiling of transcripts or their corresponding protein products in the context of pathological conditions 4,5 . G. Spekowius and T. Wendler (Eds.), Advances in Healthcare Technology,