PacBio have responded to intense competition in the sequencing market by releasing the Sequel, a machine that promises 7 times the throughput of their last machine (the RSII) at a price of $350k (the RSII cost more in the region of $750k). So they have a cheaper, higher throughput machine (though I haven’t seen cost-per-Gb figures). That’s around 7 Gigabases of reads averaging around 15Kb in length. Without doubt this is a very interesting platform and they will sell as many of them as they can produce. A sweet spot for assembly is still 50-60X for PacBio, so think 12 SMRT cells to get a human genome: let’s say £12k per genome. Edit 01/10/2015 my maths at 7am was not that good! 50X human genome is 150Gb, so that’s 21 SMRT cells and £21K per human genome. Much more expensive than Illumina’s $1000 genome, but far, far better.
I just want to say that at times I have been accused of being an Illumina- and a nanopore- fanboy; I am neither and both. I am just a fan of cool technology, from microarray in the 90s to sequencing now.
In long reads, let’s be clear, we are talking about the promise of Oxford Nanopore vs the proven technology of PacBio. And the Sequel changes the dynamics. However, the MinION fast mode is capable of throughput in the region of 7Gb (like the Sequel) and the PromethION is capable of throughput on Illumina-scale. Therefore, Oxford Nanopore are far from dead – though they need to respond.
So how does the new PacBio Sequel change the market? A lot of initial reactions I have had are that the Sequel is a real threat to Oxford Nanopore. It certainly ramps up the competition in the long read space, which is a really good thing. But actually, high-throughput long read machines like the Sequel and the PromethION don’t spell the end for one another – they actually spell the beginning of the end for Illumina – as a sequencing platform.
As soon as you have high-throughput, cheap long reads, it is in fact Illumina who face a problem. I love Illumina. When I first arrived at Roslin, I walked into our lab and (honestly!) stroked our Illumina GAIIx. Illumina have revolutionised biology. However, short reads have limitations – they are bad for genome assembly, they are bad at complex genomes, they’re actually quite bad at RNA-Seq, they are pretty bad for structural variation, they are bad at haplotypes and SNP phasing, and they are not that great at metagenomics. What has made Illumina the platform of choice for those applications is scale – but as soon as long read technologies reach a similar scale, Illumina looks like a poor choice.
The Sequel (and the PromethION) actually challenge Illumina – because in an era of cheap, long read sequencing, Illumina becomes a genotyping platform, not a sequencing platform.