Clinical massively parallel sequencing

BACKGROUND: The newest advances in DNA sequencing are based on technologies that perform massively parallel sequencing (MPS). Since 2006, the output from MPS platforms has increased from 20 Mb to >7 Tb. First-generation MPS platforms amplify individual DNA molecules to multiple copies and then interrogate the sequence of those molecules. Second-generation MPS analyzes single unamplified molecules to generate much longer sequence reads but with less output than first-generation MPS and lower first-pass accuracy. With MPS technologies, it is now possible to analyze genomes, exomes, a defined subset of genes, transcriptomes, and even methylation across the genome. These technologies have and will continue to completely transform the clinical practice. CONTENT: The major first- and second-generation MPS platforms and how they are used in clinical practice are discussed. SUMMARY: The ability to sequence terabases of DNA per run on an MPS platform will dramatically change how DNA sequencing is used in clinical practice. Currently, MPS of targeted gene panels is the most common use of this technology clinically, but as the cost for genome sequencing inches downward to $100, this may soon become the method of choice (with the caveat that, at least in the near term, clinical-grade genome sequencing with interpretation may cost much more than $100). Other uses of this technology include sequencing of a mixture of bacterial and viral species (metagenomics), as well as the characterization of methylation across the genome.