In the 1990s, PCR permitted detailed investigation of genetic material. By decade's end, researchers declared that the human genome had been mapped. Tumor-specific genetic alterations were identified amidst great hope for clinically relevant innovation. Dr Friedlander accurately voices the disappointment of many that the utility of biomarkers is "limited to experimental clinical trials." Nearly every new putative marker is examined for clinical relevance. Even those that show promise in small pilot studies seem to fade under the scrutiny of larger, well-designed confirmatory studies.