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Comment by roywiggins | Hacker News Reader

The first write-only (to a first approximation) memory storage. Reading back petabytes of DNA is going to be a challenge.

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Indeed, one could only imagine the cost of sequencing the dna to retrieve the data (not to mention the current lack of random access). Illumina's highest capacity sequencer will do 6Tb (terabases). The machine costs about half a million dollars and each run is tens of thousands of dollars, not to mention the lab costs of preparing/storing the dna. Additionally, the depth at which one would have to sequence to get _all_ of the data back reliably would be >1 meaning that every base would have to be sequence more than once (to avoid sequencing errors).

"each run is tens of thousands of dollars"

I'm not familiar with sequencing economics, would you mind explaining the cost of a "run"?

A sequencing run (at least in the context of Illumina's technology) requires a few very expensive consumable reagents: First being the flowcell (microscope slide that the dna sticks to while being read by a laser), the reagents (containing enzymes with fluorophores and other reagents for amplifying and manipulating DNA), and the actual power consumed by such machinery. This does not factor in prep/lab costs (which can be kept at a minimum with automation, but that also is a high startup cost endeavor). Each sequencing run can take ~1-3 days depending on the format.

Edit: this video may be able to explain a little better how this process works: https://www.youtube.com/watch?v=fCd6B5HRaZ8

Thanks for the explanation. I’ve seen research on graphene-based nanopore sequencing, but my knowledge and understanding are shallow.

Illumina has been stuck at 1000$ per human genome for a while.

New methods are already here, long read sequencing direct from source with minimal preparation [0]. It doesn't say much about cost, but considering reduced preparation step and smaller equipment it should be a fraction of Illumina.

[0] https://www.nature.com/articles/nbt.4125

Nanopore sequencers may require less prep and may be cheaper, but their sequencing error rate is astronomical, so you'd end up doing a lot more sequencing of the same material before you reached a consensus sequence.

I believe the nanopore sequencers would fare a lot better if the parasitic capacitance across the membrane could be minimized, by decreasing their surface area, alternatively fluorescent readout of the pore itself

https://iopscience.iop.org/article/10.1088/0957-4484/27/7/07...

Do you know anything about the speed of and techniques for read? What advances in sequencing will be required to support efficient and quick read?

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