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Re:Sequencing your DNA with a USB dongle and open source code by bioinformatics on Wednesday February 03, 2021 @11:14AM (#26015059)
Computational requirements are quite high, but OK if you have good GPUs on hand. A coronavirus sequenced sample on the fast mode without GPUs would take 3-4 hours to complete, while on the high accuracy mode days. GPU access would speed up performance considerably.

Error rate for MinIONs is still quite high (10-15%), so a human genome sequencing would be quite inaccurate in some regions.

Sequencer is quite cheap, reagents and flow cells are a little bit more expensive.

Re:Sequencing your DNA with a USB dongle and open source code by Ovah on Wednesday February 03, 2021 @11:51AM (#26015601)
Thank you. The upfront cost of the sequencer sure makes it tempting at first sight.

My desired hobbyist use case is to key out plants, lichens and mushrooms that I find in the field. I have the bioinformatics knowhow just need the hardware. 3-4h seems lika a long time for a genome that is <30k nucleotides long. Mushrooms on average seem to have almost as many genes as coronaviruses has nucleotides. I guess partial sequences (and thus reduced comp time?) might do the trick but it's probably hard to target those partial reference sequences with a long-read method like NanoPore.

Re:Sequencing your DNA with a USB dongle and open source code by alwaysdoit on Wednesday February 03, 2021 @12:56PM (#26016655)
If you repeat the process many times will it reduce that error rate, or are the errors non-independent?
Re:Sequencing your DNA with a USB dongle and open source code by staplung on Wednesday February 03, 2021 @03:02PM (#26018423)
Unfortunately, with nanopore the errors are biased so you tend to get errors in the same places. All sequencing techniques also have error rates but some are unbiased so running a single sample through (which will usually have many, many copies of any sequence) will average out to a good read of the sequence.

Some good info on next-gen sequencing techniques: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3841808/

Re:Sequencing your DNA with a USB dongle and open source code by tdido on Wednesday February 03, 2021 @03:26PM (#26018658)
Still, some of the errors can be compensated for with more coverage. So if you can manage 20-30X you're left with the homopolymer problem (nanopores can't tell how long a stretch of the same repeated nucleotide is, because you can't control how long the sensed kmer stays in the pore), but lots of other types can be improved quite a lot.
Re:Sequencing your DNA with a USB dongle and open source code by alextheparrot on Wednesday February 03, 2021 @01:11PM (#26016931)
Last time I looked into Nanopore the cost wasn't that much better where you'd even consider this experiment.

On the other hand, when doing a genome assembly, the Nanopore reads are good for a draft sequence and then the Illumina reads can be used to polish the sequence.

Re:Sequencing your DNA with a USB dongle and open source code by gnramires on Wednesday February 03, 2021 @12:35PM (#26016349)
Is the error rate per base pair?