The analyte identification is performed using four different types of high-performance Ultra Performance Liquid Chromatography (UPLC) instruments paired with Mass Spectrometry (UPLC/ MS). The identification of each molecule is confirmed against a proprietary chemical library consisting of accurate molecular weight/mass, mass spectral fragmentation patterns, and additional reference data. Overall process variability is assessed using stable isotope standards to monitor the performance of the assay and for quality control purposes. The signal intensity of each metabolite in the panel is compared to its signal intensities from a reference cohort to calculate a Z-score that is representative of the standard deviations from the mean.
Limitations: MetaSign detects small molecules between 50-1,500 Daltons, and any metabolites beyond this size range such as proteins, oligosaccharides, glycosylation metabolites, and certain lipids will not be detected. This test may fail to detect some metabolites for various reasons including, but not limited to: a) the presence of an analyte below the detection level, b) interference from other metabolites and c) the need for special processing. Improper sample processing and handling can cause sample degradation and adversely impact the interpretation of data/results.
This test is performed in collaboration with Metabolon Inc., Durham, NC