Digital Polymerase Chain Reaction - Development

Development

The physically partitioned, macro-chamber digital PCR concept was conceived in 1992 by Sykes et al. using nested PCR.

Fundamental to its current implementation, an important development occurred in 1995 with co-inventions by Brown at Cytonix and Silver at the National Institutes of Health of single-step quantitization and sequencing methods employing nano-scale physical containment arrays (Brown, Silver), and open chambers (Brown) using localized clonal colonies in 1D and 2D capillaries, macro volumes, gels, free chambers, affinity surfaces/particles and immiscible fluid containments, resulting in a 1997 U. S. Patent and subsequent divisional and continuation patents. The concepts of electrowetting and digital microfluidics were further introduced (Brown) as a means of manipulating nano fluid volumes and carrying out Digital PCR.

Digital PCR has been shown to be a promising surveillance tool for illnesses such as cancer, and as a vital front end to determining genomic content, including sequencing the human genome.

Based on the concept Vogelstein and Kinzler developed a technology called BEAMing (Beads, Emulsion, Amplification, Magnetics) and quantified KRAS mutations in stool DNA from colorectal cancer patients.

Significant additional developments have included using emulsion beads for digital PCR by Dressman and colleagues.

It has also proved useful for the analysis of heterogeneous methylation.

In 2006 Fluidigm introduced the first commercial system for digital PCR based on integrated fluidic circuits (chips) having integrated chambers and valves for partitioning samples.

In 2008, Inostics started to provide BEAMing digital PCR services for the detection of mutations in plasma/serum and tissue.

In November 2010, Life Technologies acquired Biotrove and commercialized a digital PCR product line for the OpenArray system.

QuantaLife developed the Droplet Digital PCR (ddPCR) technology, which partitions a sample into 20,000 droplets and provides digital counting of nucleic acid targets. In 2011, Quantalife was acquired by Bio-Rad Laboratories.

In 2012, RainDance Technologies launched a digital PCR platform based on its picoliter-scale droplet technology, which generates up to 10 million picoliter-sized droplets per lane. The technology was first demonstrated in a paper published in Lab on a Chip by scientists from Université de Strasbourg and Université Paris Descartes. Later that year, RainDance Technologies announced a partnership with Integrated DNA Technologies to develop reagents for the digital PCR platform.

Digital PCR has many applications, including the detection and quantification of low-level pathogens, rare genetic sequences, copy number variations, and relative gene expression in single cells. No other method provides this information with such accuracy and precision. Clonal amplification enabled by single-step digital PCR is a key factor in reducing the time and cost of many of the "next-generation sequencing" methods and hence enabling personal genomics.