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How would it let you frame convenient suspects? Surely you would need to place that suspects DNA at the scene, in which case you already have it...? Where does

How would it let you frame convenient suspects? Surely you would need to place that suspects DNA at the scene, in which case you already have it...? Where does the database come into this?

csallen 8y ago
Just because the government finds your DNA at the crime scene doesn't mean they know it's yours. They have to match it against some sort of database that connects the DNA to your identity.
- vetinari 8y ago
  With enough corruption, they might also "find" it on the crime scene.
  - politician 8y ago
    Exactly, while DNA may identify an individual with high precision, we have to trust that that DNA was actually associated with the location or event. Consider a public bathroom: how much DNA is at that location? How much is relevant to the event? Consider a corrupt lab tech: The DNA at the event might be reported as DNA from their database. Does a defense attorney get to see the untainted sample? Consider a corrupt/hacked DNA database: The database might report that the DNA belongs to one individual when it actually doesn't. Does a defense attorney even get to see the source code? In these scenarios, the link to any individual is either of little consequence, or fraudulent.
    - carbocation 8y ago
      And in case this sounds implausible, a corrupt lab tech handled 60,000 cases in MA: https://www.cbsnews.com/news/annie-dookhan-chemist-at-mass-crime-lab-arrested-for-allegedly-mishandling-over-60000-samples/ https://www.cbsnews.com/news/annie-dookhan-chemist-at-mass-c...
      - deleted 8y ago
        [deleted]
- notahacker 8y ago
  There's a case against globally accessible DNA databases from the point of view of dragnet approaches picking up people whose connection to the crime scene is either totally incidental or actually nonexistent and purely down to data mixups, but that's a largely separate issue from authoritarian police trying to massage the evidence in a case against a particular person. If you're already a "convenient suspect" the police wish to build a case against, they don't need to find you on a consumer genetics database to be able to obtain a sample of your DNA or strongly hint that they expect to be able to use DNA evidence (truthfully or otherwise) to send you away for a very long time if you're not willing to consider moving to plea bargaining territory.
ivalm 8y ago
Right now you do not have a convenient way to force your target to submit to a DNA test. This way you can frame someone by placing their DNA at the crime scene and then having it "discovered" using DNA testing company data.
- zaphirplane 8y ago
  Because there is a line when framing people never to be crossed ;) come on throw in a shoe print,a witness, fake signature. something extra
freeflight 8y ago
> Where does the database come into this? "The scientists fabricated blood and saliva samples containing DNA from a person other than the donor of the blood and saliva. They also showed that if they had access to a DNA profile in a database, they could construct a sample of DNA to match that profile without obtaining any tissue from that person." [0] [0] https://www.nytimes.com/2009/08/18/science/18dna.html https://www.nytimes.com/2009/08/18/science/18dna.html
- phs318u 8y ago
  > if they had access to a DNA profile in a database, they could construct a sample of DNA to match that profile Oh wow. Really??? Any experts in this field reading this? Would love to hear someone with pertinent authority tell us this isn't true. (Please don't be true)
  - lostlogin 8y ago
    There links in that NY Times article and they look like reasonable sources.
  - hedora 8y ago
    It is simple to do, assuming the police are using genotyping instead of a full genome sequence for the match. (This is the common case today.) Genotyping works as follows: there are thousands of regions of “junk” dna in the human genome that don’t code for anything. There is no evolutionary pressure to preserve the exact length of these regions. (They probably help the chromosomes fold up in ways that encourage/suppress the activity of certain genes, help the molecule be more robust, etc). Since there is no evolutionary pressure to preserve the regions, they tend to be full of hard to copy junk like ATAT..... that tends to change every few generations. Genotyping works by isolating a bunch of these regions, and using PCR to create millions of copies of each region (with ~one sample per region). Finally, you put a drop of the each sample and some die on a electrophoresis gel, and apply some current. Different sized molecules move at different rates, so this gives you a crude measurement of the length of each molecule. To fake a match, all you need to do is produce something that will trick the first step of all this into grabbing molecules of your choice of length, which will fool the rest of the process. If you want to see how that would work, read up on “pcr primers”. Source: I used to work in a genotyping/sequencing lab as a bioinformatician, and worked on algorithms that did exactly this sort of analysis (not the forgery bit though).
clouddrover 8y ago
> Surely you would need to place that suspects DNA at the scene Don't underestimate DNA transfer. Your DNA can end up in locations you have never been: https://www.wired.com/story/dna-transfer-framed-murder/ https://www.wired.com/story/dna-transfer-framed-murder/
kingkawn 8y ago
With Pcr you’d only need a very small sample to produce enough DNA to smother a crime scene in “evidence”

How would it let you frame convenient suspects? Surely you would need to place that suspects DNA at the scene, in which case you already have it...? Where does the database come into this?

csallen 8y ago

Just because the government finds your DNA at the crime scene doesn't mean they know it's yours. They have to match it against some sort of database that connects the DNA to your identity.

vetinari 8y ago
With enough corruption, they might also "find" it on the crime scene.
- politician 8y ago
  Exactly, while DNA may identify an individual with high precision, we have to trust that that DNA was actually associated with the location or event. Consider a public bathroom: how much DNA is at that location? How much is relevant to the event? Consider a corrupt lab tech: The DNA at the event might be reported as DNA from their database. Does a defense attorney get to see the untainted sample? Consider a corrupt/hacked DNA database: The database might report that the DNA belongs to one individual when it actually doesn't. Does a defense attorney even get to see the source code? In these scenarios, the link to any individual is either of little consequence, or fraudulent.
  - carbocation 8y ago
    And in case this sounds implausible, a corrupt lab tech handled 60,000 cases in MA: https://www.cbsnews.com/news/annie-dookhan-chemist-at-mass-crime-lab-arrested-for-allegedly-mishandling-over-60000-samples/ https://www.cbsnews.com/news/annie-dookhan-chemist-at-mass-c...
    - deleted 8y ago
      [deleted]
notahacker 8y ago
There's a case against globally accessible DNA databases from the point of view of dragnet approaches picking up people whose connection to the crime scene is either totally incidental or actually nonexistent and purely down to data mixups, but that's a largely separate issue from authoritarian police trying to massage the evidence in a case against a particular person. If you're already a "convenient suspect" the police wish to build a case against, they don't need to find you on a consumer genetics database to be able to obtain a sample of your DNA or strongly hint that they expect to be able to use DNA evidence (truthfully or otherwise) to send you away for a very long time if you're not willing to consider moving to plea bargaining territory.

ivalm 8y ago

Right now you do not have a convenient way to force your target to submit to a DNA test. This way you can frame someone by placing their DNA at the crime scene and then having it "discovered" using DNA testing company data.

zaphirplane 8y ago
Because there is a line when framing people never to be crossed ;) come on throw in a shoe print,a witness, fake signature. something extra

freeflight 8y ago

> Where does the database come into this? "The scientists fabricated blood and saliva samples containing DNA from a person other than the donor of the blood and saliva. They also showed that if they had access to a DNA profile in a database, they could construct a sample of DNA to match that profile without obtaining any tissue from that person." [0] [0] https://www.nytimes.com/2009/08/18/science/18dna.html https://www.nytimes.com/2009/08/18/science/18dna.html

phs318u 8y ago
> if they had access to a DNA profile in a database, they could construct a sample of DNA to match that profile Oh wow. Really??? Any experts in this field reading this? Would love to hear someone with pertinent authority tell us this isn't true. (Please don't be true)
- lostlogin 8y ago
  There links in that NY Times article and they look like reasonable sources.
- hedora 8y ago
  It is simple to do, assuming the police are using genotyping instead of a full genome sequence for the match. (This is the common case today.) Genotyping works as follows: there are thousands of regions of “junk” dna in the human genome that don’t code for anything. There is no evolutionary pressure to preserve the exact length of these regions. (They probably help the chromosomes fold up in ways that encourage/suppress the activity of certain genes, help the molecule be more robust, etc). Since there is no evolutionary pressure to preserve the regions, they tend to be full of hard to copy junk like ATAT..... that tends to change every few generations. Genotyping works by isolating a bunch of these regions, and using PCR to create millions of copies of each region (with ~one sample per region). Finally, you put a drop of the each sample and some die on a electrophoresis gel, and apply some current. Different sized molecules move at different rates, so this gives you a crude measurement of the length of each molecule. To fake a match, all you need to do is produce something that will trick the first step of all this into grabbing molecules of your choice of length, which will fool the rest of the process. If you want to see how that would work, read up on “pcr primers”. Source: I used to work in a genotyping/sequencing lab as a bioinformatician, and worked on algorithms that did exactly this sort of analysis (not the forgery bit though).

clouddrover 8y ago

> Surely you would need to place that suspects DNA at the scene Don't underestimate DNA transfer. Your DNA can end up in locations you have never been: https://www.wired.com/story/dna-transfer-framed-murder/ https://www.wired.com/story/dna-transfer-framed-murder/

kingkawn 8y ago

With Pcr you’d only need a very small sample to produce enough DNA to smother a crime scene in “evidence”