BGI's Industrial Scale Sequencer Challenges Illumina's HiSeq Line

By Bio-IT World Staff

June 8, 2015 | BGI, the Shenzhen-based global genomics corporation, revealed its first DNA sequencing instrument for worldwide markets over the weekend at the European Human Genetics Conference in Glasgow. (The company also manufactures two sequencers for the Chinese market, where they are approved for clinical use by the Chinese FDA.) The new sequencer, named Revolocity, is based on technology developed by Complete Genomics, BGI's subsidiary in Mountain View, California, which has been offering its own sequencing system as a service for years but has not previously made its instruments commercially available.

As anticipated, Revolocity is designed for ultra-high-throughput applications, sequencing many whole human exomes or genomes in parallel; BGI claims the system can currently deliver 10,000 whole genomes a year and aims to triple that output with future upgrades. Each Revolocity system also comes with a series of instruments for preparing DNA from raw samples (including blood and saliva), as well as software to analyze the results of sequencing. These features are not standard with any competing platform, although other manufacturers are increasingly releasing bolt-on instrumentation to perform at least part of the sample preparation process. As with Complete Genomics' in-house process, the Revolocity system achieves this level of automation with a combination of third-party and custom hardware and software.

The focus on whole human genomes at an industrial scale places Revolocity firmly in competition with Illumina's HiSeq series, especially the HiSeq X, HiSeq 4000 and HiSeq 3000 models whose patterned flow cells allow for very high parallelization of sequencing-by-synthesis reactions. A battery of ten HiSeq X instruments, which Illumina sells for $10 million, can purportedly sequence 18,000 whole human genomes a year; no competing system now on the market, other than Revolocity, produces DNA data at a comparable rate. BGI will sell Revolocity for $12 million per system, and has already announced its first two customers, Mater Health Services of Australia and Radboud University Medical Center in the Netherlands, both involved in clinical diagnostics and research. (Illumina has sold over a dozen HiSeq X Ten systems, many of them to basic research-oriented centers.)

The HiSeq series and Revolocity use markedly different sequencing systems — Complete Genomics' "DNA nanoball"-based approach, in which short DNA sequences are circularized and segregated onto a flow cell before being interrogated, is like nothing else in the world of genomics. Nonetheless, the two technologies have similar limitations. Both are highly specialized: the HiSeq X has been deliberately formatted to support only whole human genomes, while Revolocity is limited by technical constraints to only whole human genomes and exomes. Both offer short read lengths, which are sufficient to find single-nucleotide variants and short insertions and deletions when the results are compared to a reference sequence, but can mask larger structural variation in the genome.

Despite these challenges, large-scale sequencing is on the rise, with more and more centers lining up to undertake ambitious projects that demand huge volumes of DNA data. While BGI has an uphill climb to convince many customers to adopt its platform's less familiar technology, the introduction of Revolocity means Illumina no longer has this field all to itself.