Wednesday, September 13, 2017

I Got Points Off Once For Having A large Percent Error, What Does NY Get?

As a normal person, I am one to think of ways to get out of legal conflict (aka I done goofed and got myself behind bars).  But today I am here to say, "Katie, look no further." Yes, ladies and gents, I am here to inform you that the people in charge of putting the convicts behind bars have come in clutch. According to a piece by Lauren Kirchner for they New York Times, New York City's FBI labs have been using faulty technology to do the impossible: identify suspects based on only a few picograms of DNA. And no, picograms is not a gram of the spicy and colorful salsa of the Spanish culture, pico de gallo.  Picograms is a really really really small sample of DNA (I'm talking 10E-12) that the public and some uninformed law enforcement believe a scientist can pinpoint to a certain person's DNA sequence. This feat of course came with consequences, such as sending innocent people to jail or not sending anyone to jail at all (including the suspects that were guilty!)  It seems that in a heavily concentrated bureaucratic system, the people ordering the sample to be analyzed did not realize that they were asking for something that is beyond the technology that is currently available.  But like any scientist that wants to please the people in charge of them, Dr. Theresa A. Caragine created new DNA analysis tests that is able to analyze smaller amounts of DNA than the technology that were being used currently (Kirchner, New York Times).  One technique that Dr. Caragine developed was the high sensitivity test.  This test pushed the usual technique of amplification through polymerase chain reaction a few cycles more to amplify the small amount of DNA a total of 31 times (compared to 28).  This allowed a larger sample to be analyzed, however like all good things, there is always a "but."  With larger amplification of the DNA sequence came larger amplification of imperfections from missing or contaminated DNA sequences.  Accounting for this, Dr. Caragine had to agree to only use samples that were 20 picograms or more before the use of her technique was approved by her directors.  This policy was not carried out correctly and samples as low as 14 picograms have been used as evidence to convict the accused, creating a larger margin of error.  This would be fine except in some cases, people who have had no other evidence against them have been sent to jail because of this technique.  This meant people who were going to be found innocent saw a different fate because of a technique that has an average error of about 20%.  After five years of continuous use, the techniques that Dr. Caragine had developed are finally going to be suspended until the percentage of error is at the more accepted value of less than 5% (Kirchner, Propublica).  Unfortunately, if I wanted to rob a bank in the city of New York and leave no trace except for a few skin cells, I'm going to have to pull a 30 second montage and get it done quickly.

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