Nanopore Sequencing Companies: Geneus

A while ago I looked at 4 Chinese nanopore sequencing startups. Since then the BGI nanopore sequencer has been “released”. There’s stealthy entity called “Lunar Bio” and in addition to this we have AxBio which appears to be US based but with a strong Chinese presence.

Recently I came across two more Chinese Nanopore sequencing companies, bringing the total to 9!

Let’s take a quick look at the first of these two “new to me” nanopore sequencing companies, Geneus. I’ll cover the other tomorrow (subscribe for that!)

Geneus

They list some impressive specs on their site (99% accuracy) but I’m mostly interested in the technical description, as this should give a better sense of the limitations of the approach.

There are a couple of statements that stand out. The first is:

"Super capacitors are adopted. Powered by alternating current, the size of the sequencing units is reduced to several micrometers. Combined with very large scale integrated circuits, more than 1 million sequencing units can be integrated on a chip of 1 cm."

These statements would be inline with those Roche appears to be suggesting. A significant advance over the state of the art (Going from 100+ microns and 1000s of wells on Oxford Nanopores devices to <10 micron and 1 million).

A huge advance, but not a lot of information on if/how they’ve achieved this.

In terms of the chemistry, this doesn’t appear to be standard ONT-style stranded sequencing:

Single-molecule side synthesis Side nanopore Sequencing (NSS)

The basic principle of NSS sequencing technology adopted today is to combine the protein nanopore detection method with the system of "synthesis and sequencing". Four different special modification chains are added to the base end of the nucleic acid chain to be tested. During the replication process of the nucleic acid chain to be tested by polymerase, four kinds of chains pass through the nanopore and produce different characteristic blocking currents. The characteristic blocking current is monitored in real time by IC-MEMS integrated chip, the current change information is collected, the types of replicated nucleotides are analyzed, and the sequence of nucleic acid to be tested is obtained.

This sounds very much like the Genia approach which was also being adopted by AxBio, in which a complementary strand is synthesized containing special tags which go down the pore: