The 10X Chromium library preparation system is a unique approach to leveraging single molecular barcoding. In the genomic DNA mode, the Chromium instrument uses molecular barcoding of high molecular weight DNA to generate long-read sequencing data using Illumina short read sequencing. In the single cell mode, the instrument can be used to generate single cell transcriptome data and profile an entire cell population.
Using high molecular weight DNA, (≥50kb) the Chromium instrument enables individual barcoding of long stretches of DNA. The long DNA fragments are then reduced to smaller sizes for Illumina short read sequencing, each retaining the barcode assigning it to the larger fragment. The libraries are constructed from these shorter fragments and sequencing on our Illumina HiSeq 2500s.
Using the single cell mode on the Chromium instrument allows for the molecular profiling of a cell population. RNA transcripts from individual cells are barcoded to allow full transcriptome sequencing of individual cells. The instrument can profile from 1000 to 10,000 cells per experiment, which are then used to generate a single library for sequencing. Molecular barcodes assign individual transcript reads to a particular cell. Using the transcription profile, researchers can identify individual cell types in their population.