Genomes III

Genomes III

Solexa/Illumina

The history of the Solexa technology begins as well in Cambridge, but in the mid-1990s. 


Doctors S. Balasubramanian and D. Klenerman funded Solexa in 1998. After some years, Solexa would go out of Cambdrige and turn into an international company that would be acquired by Illumina in 2007, a year after releasing their first commercial sequencing plataform, the Genome Analyzer, which remains the leader among the NGS platforms.

The Solexa technology is based on the incorporation of reversible fluorescent terminators and in the generation of clusters -somewhat similar to polonys- of DNA fragments by bridge amplification.

Ion Torrent

Personal Genome Machine
Source: Forbes

Unlike the already mentioned technologies, the Ion Torrent technology does not rely on optic systems to sequence a strand of DNA. 


This technology uses semiconductors that detect -by changing the charge of an ion detector and transforming it to voltage- the hydrogen ions that are released when the DNA polymerase incorporates a dNTP. 


The core of an Ion Torrent sequencer fits into a chip; the Personal Genome Machine (released in December 2010) is still the most compact sequencer.

Nanopore

The nanopore sequencing technology does not require amplification steps nor optical systems. It is based on the electrophoretic translocation of a DNA molecule through a nanometric pore and on the change of the electric characteristics of that pore.

MinION prototype

The technology has been around in continuous development since the mid-1990s, but the recent press releases of Oxford Nanopore have increased expectations, because of the characteristics of their platforms and as they have settled the goal of sequencing a human genome in just 15 minutes.

The platforms announced by Oxford Nanopore are GridION and its miniaturized version, MinION, which can be directly plugged by an USB port to transmit data in real time, even from samples such as blood, serum and environmental samples.

As Genomes Unzipped has commented, in the future "no-one will remember that they sequenced a genome for 20% cheaper. They will remember that they used a laptop computer to sequence DNA straight from a rabbit."

MALS/Gö/Mar 2012

Translated: Apr 2012