10/14/2011

DNA Evidence Can Be Faked - So Why Do We Continue to Consider DNA Infallible?

DNA is easier to fake than fingerprints at a crime scene, according to scientific experts, and this is something that's been public knowledge for several years now.  Read the 2009 article in the New York Times, for example; written by Andrew Pollack, entitled "DNA Evidence Can Be Fabricated, Scientists Show," it's got lots of details.  Or go peruse the research paper written by Dr. Daniel Frumkin in Genetics, a source mentioned by Pollack in his coverage. 

Why Don't We Know That DNA Evidence Is Not 100% Trustworthy?

No one talks about this much, and I wonder how many people really know that we cannot trust DNA just because they do it on TV.  Heck, in one Law and Order: Special Victims Unit episode, even the TV cops found out that the DNA in their case had been faked.  (If you're interested in watching, that was episode 9 of season 11, entitled "Perverted." Watch it here.)

Faking someone's DNA is easy to do, and it doesn't take all that much skill or education.
  Apparently, all an evildoer would need is the saliva sample of one person - which they could get off a tossed coffee cup or drinking straw or fork or spoon (well, you get the idea), or from a hair sample, again something that could be pulled from the trash.  Then, through a process called "whole genome amplification," the evildoer can create fake DNA samples of that person which evildoers, being what they are - evil doing - could use to cause all sorts of mayhem. 

But that's not the whole story.  It's even easier that this for the sinister scientist who wants to fake someone's DNA.  If they don't have that tossed coffee cup or hair from a comb, no problem.  DNA can also be faked if they can get access to the person's DNA profile, stored somewhere in a computer database.  They can cook up some fake DNA using the info on the database as their recipe.

So, why aren't we being told about this?  We all need to know that DNA isn't infallible, that we shouldn't automatically trust DNA evidence. 

Why?  Well, I'm just as concerned about overzealous prosecutors as I am about outlaws taking advantage of this opportunity.  Seems to me that it is only by greater public awareness that this can happen (and that questionable DNA evidence can be tested to see if it has been faked) that an evildoer trying to plant DNA evidence for sinister purposes can be thwarted.