Air is full of DNA

Posted by howrude 2 days ago

Comments

Comment by azalemeth 57 minutes ago

I do often wonder about stories like this in the context of forensic science – my (incomplete!) understanding a lot of the time suspect DNA samples are taken from small areas and amplified significantly with high-cycle count PCR. I'd worry that any jury presented with a statistical argument about a fragment of somebody's DNA being very unlikely ("1 in 100 million") to be different to the sample found at the scene would not be aware of all of the potential systematic reasons why the actual true probability may be much, much higher.

Comment by Terr_ 36 minutes ago

Probability seems to be one of those things humans habitually mess-up at.

"The chances of this person's unique DNA showing up at the scene are a zillion to one!"

"What does that really mean when the sample also contains unique DNA for a hundred other people? Did all of them commit the crime as a group?"

Comment by butvacuum 2 days ago

buried the lede, imho: we have enough DNA profiles to match their sampling up with.

I'm always stunned when reminded that a full genome sequencing has gone from Human Genome Project's extreme cost and (edit: glacial) speed to using seqencing as the easy button.

I hear we've also got machines that'll seqence, fit on a bench, and cost high five/low six figures. They've got issues to work out still though- iirc something about damaged sections causing issues.

Comment by smolder 1 hour ago

Paleontology has been really helped by the ease of sequencing, to the point where many evolutionary arguments are moot. Humans are apes, birds are dinosaurs. Some people still dispute it, but not with evidence on their side.

Comment by Terr_ 34 minutes ago

> Some people still dispute it

I particularly like this Futurama clip on the subject. https://m.youtube.com/watch?v=VzGtk7Ip4NU

Comment by cmrx64 2 days ago

four figures these days. fits in your hand. nanopore is a revolution. https://nanoporetech.com/products/sequence/minion

there’s youtubers that have videos about doing this in a home wetlab. very achievable. some amateur soil biologists using this to try and sample microdiversity as the planet… humanifies.

Comment by dubi_steinkek 19 hours ago

Do you have links to these youtubers? Sounds interesting

Comment by samplatt 1 hour ago

Not OP, but The Thought Emporium is a personal favourite. Their name belies the hands-on nature of their videos.

https://www.youtube.com/watch?v=F0_q-fD_lyU

Comment by globular-toast 1 hour ago

Should be noted, though, the cheaper/quicker techniques do still come with compromises compared to the "gold standard" technique used for the Human Genome Project.

Comment by seydor 1 hour ago

Let's wait for smartphones with nanopores

Comment by madaxe_again 2 hours ago

I was chatting with a biologist friend a while back, and one tidbit he dropped in was that any sample of air from anywhere on earth will likely contain the dna of organisms unknown to science, so abundant the tree of life is.

Comment by dang 3 hours ago

[stub for offtopicness]

Comment by baxtr 4 hours ago

> Scratch your head and you’ll release DNA-rich cellular material into the air. There, it will mingle with DNA from myriad other sources: your own and others’ exhalations and exfoliations, fragments of hair, feathers, excrement, pollen and spores, and microorganisms such as viruses and microalgae. This DNA, which can include segments that are tens of thousands of base pairs long, will then wander the air for perhaps a few days, often clinging to dust particles. It can travel distances that range from a few metres to several thousand.

Comment by shevy-java 4 hours ago

[flagged]

Comment by dhruv3006 4 hours ago

Why is nature suddenly click bait - changing times I guess.

Comment by cmos 1 day ago

As is the Ocean.

Comment by tim333 1 day ago

Cool.

I think they had to delete all the sequencing data from the Wuhan Institute of Virology so stuff in the air wouldn't show up.

Comment by shevy-java 4 hours ago

That was never a convincing argument, IMO. Just as US institutes would claim that China is responsible, by the same token the argument works on any other lab too - yet the media did not present in that way. Ever. That's not accurate reporting; that's an attempt at victim blaming. Next thing someone may do is give a powerpoint presentation about weapons of mass destruction in some far-away country ...

Comment by philipallstar 1 hour ago

Actually, the US did a lot to downplay the idea that the nearby lab in Wuhan that was doing gain of function research on coronaviruses was in any way involved, to the extent that you'd get shadow-banned on Twitter for mentioning it.

Comment by popopo73 4 hours ago

    >Just as US institutes would claim that China is responsible, by the same token the argument works on any other lab too - yet the media did not present in that way. Ever. That's not accurate reporting; that's an attempt at victim blaming.

So your idea of accurate reporting is to apply whataboutisms?