A China-made second-generation DNA sequencer, BIGIS-4, has recently been developed and put into trial operation. The sequencer is jointly developed by Beijing Institute of Genomics (BIG) and Institute of Semiconductors (IS), Chinese Academy of Sciences (CAS), with financial support of the scientific equipment development program of CAS.

BIGIS-4 is a scalable, highly integrative system for determining nucleotide sequences based on the pyrosequencing chemistry. The reaction modules are in four separate identical chambers and share one fluidics system. Capable of handling variable amounts of samples, one to four reaction module(s) can be launched to accommodate the throughput requirement. The apparatus is able to sequence 600-800 million bases in one run, with average length of 600-700 bases. Compared to market available instruments, BIGIS-4 system has advantages in sequencing performance and cost.

Using the BIGIS-4 system, researchers of BIG have successfully completed the genome assembly of a Gram-negative bacterium Glaciecola mesophila sp. nov. isolated from marine invertebrate specimens. No systematic low-quality data was detected beyond expected homopolymer-derived errors. The research results were published in Science China Life Sciences in August 2011, which is the first report based on domestic sequencers.

At present, the research group is carrying out further R&D to improve reagents, seq-plate, and post-processing software. The domestication of the entire system is expected to be accomplished in the yearend.

Read length distribution from the BIGIS-4 one-reaction module