That's true in targeted sequencing, but when you try to sequence a whole genome, this is unlikely.
Whole-genome shotgun sequencing is pretty cheap these days.
The person you are replying to doesn't give any specific numbers, but in my experience, you aim for 5-20x average coverage for population level studies, depending on the number of samples and what you are looking for, and 30x or higher for studies where individuals are important.
For context, coverage refers to the (average) number of resulting DNA sequences that cover a given position in the target genome. Though there is of course variation in local coverage, regardless of your average coverage, and that can result in individual base-calls being being more or less reliable
You need multiple flow cells or a higher capacity flow cell to get anything close to 1X on an unselected genome prep.
Shotgun sequencing isn’t probably what you meant to say - this is all enzymatic or, if it’s sonicated, gets size selected.
But if we are talking nanopore sequencing, then yes, you need multiple flowcells. Which is not a problem if you are not a private person attempting to sequence your own genome on the cheap
You can do nanopore PCR/cDNA workflows right up to the largest known mRNAs (13kb).
Edit:
I’m not sure if you’re saying that you can’t do a 5/20/30X genome on nanopore - that’s also not true. It only makes sense in particular research settings, of course.
https://pmc.ncbi.nlm.nih.gov/articles/PMC3849550/
You can sequence a human genome on a MinION - but you need to purchase 5 flow cells to reach 11X (if they are used correctly).. https://nanoporetech.com/news/news-human-genome-minion
Yes... and that is why I said that the presence of PCR does not imply short reads.
> You can sequence a human genome on a MinION - but you need to purchase 5 flow cells to reach 11X (if they are used correctly).. https://nanoporetech.com/news/news-human-genome-minion
THat's why I said that 5/20/30X coverage is possible in the appropriate research setting
I can't 100% prove it wasn't a legit mutation but our lab did several tests where we sequenced the same sample with both Illumina and Nanopore, and found Nanopore to be less than perfect even with exteme depth. Like, out depth was so high we routinely experienced overflow bugs in the assembly software because it stored the depth in a UInt16.