Hacker News new | past | comments | ask | show | jobs | submit
car | on: To deter bioterrorism, U.S. imposes new rules on ordering synthetic DNA
The device used to make oligonucleotides is pretty much an inkjet printer, from there it's cleverly applied enzymes to assemble the full strand.

Usually the synthesis of oligonuclotides is done with phosphoramidite chemistry [0]. So tell us more about those enzymes to make DNA molecules from scratch.

[0] https://www.twistbioscience.com/blog/science/simple-guide-ph...

mbreese | parent | next
I’m pretty sure they were talking about how you can combine synthesized oligos into longer fragments when you are starting with smaller oligos. I’m guessing that they were referring to using different restriction enzymes from that point on.

Unless we are talking about really long oligos (which is harder and $$$), you’ll need some post-synthesis enzymatic work to get your full strand.

fc417fc802 | root | parent
Yes I also read the comment that way. The inkjet printer remark presumably refers to benchtop DNA synthesis machines which have been commercially available for a while now. (The linked article mentions the possibility of buy-back programs for old machines that don't enforce any restrictions.)

I guess it's not a bad idea to put basic hurdles in place but it would be a serious mistake to see this as any sort of comprehensive preventative. DNA just isn't difficult to manipulate.

XorNot | root | parent
The thing is DNA just also isn't dangerous. It's fragile and everything in the environment destroys it - as noted it's literally a everything else which is the hard part.

This reeks of the Longtermists getting their influence into government. They were doing an entire round on YouTube about a year ago.

loading story #50450537
amirhirsch | parent
Ansa Bio uses an engineered terminal deoxynucleotidyl transferase (TdT) enzyme to synthesize the oligos themselves, rather than using phosphoramidite chemistry. Each enzyme is tethered to a single nucleotide, allowing it to extend the DNA strand by exactly one base. The tether is then cleaved and the cycle repeats.

This works in aqueous solution under mild conditions and enables synthesis of much longer oligos (~1,000 bases), which can subsequently be assembled into 50 kbp constructs.

Not sure about that inkjet printer analogy.