L1000 is a gene-expression profiling assay based on the direct measurement of a reduced representation of the transcriptome and computational inference of the portion of the transcriptome not explicitly measured. The number of landmark transcripts whose abundance is measured directly is approximately one thousand. Eighty additional invariant transcripts are also explicitly measured to enable quality control, scaling and normalization. Measurements of transcript abundance are made with a combination of a coupled ligase detection and polymerase chain reaction, optically-addressed microspheres, and a flow-cytometric detection system.
Watch the video below for a virtual laboratory tour through the L1000 assay process in the Broad Institute labs.