Molecular signatures constitute one of the most important translational and basic science developments enabled by recent high-throughput molecular assays. A perplexing phenomenon that characterizes high-throughput data analysis is the ubiquitous multiplicity of molecular signatures. This phenomenon has far-reaching implications for biological discovery and development of next generation patient diagnostics and personalized treatments. Currently, the causes and interpretation of signature multiplicity are unknown, and several—often contradictory—conjectures have been made to explain it. The authors shed light on the causes of signature multiplicity and provide a method for extracting all equivalently accurate signatures from high-throughput data. (See Statnikov and Aliferis, e1000790).

Image Credit: William Sommer (New York University Langone Medical Center).