Forensic Dna Profiling
In trials where a defendant may be given a life or death sentence, is it reasonable to place so much faith in genetic forensic results? I believe that although DNA profiling is a great tool for identifying suspects and victims, at our current technological state, we should use it as supplemental evidence rather than assume it is 100% foolproof. DNA is 99. 9% identical throughout all human beings (Lander). So how is it possible that DNA is used as evidence in the courtroom? DNA gathering is less invasive than a blood test, as a simple cheek swab can be sufficient for analysis.
The tiny fraction of DNA that is unique to individuals is what is used in forensic testing. In the early stages of DNA forensics, restriction fragment length polymorphisms (RFLP) were used by digesting DNA with restriction enzymes and then analyzing the resulting fragment lengths which were unique to individuals (Davidson). One of the main techniques used nowadays is the combination of PCR and short tandem repeats. PCR, or polymerase chain reaction, is a method used to amplify sequences of DNA.
By amplifying specific polymorphic regions of DNA, unique number of repeats at specific locations can be assigned to individuals (Human Genome Project). DNA analysis has become the most advanced method of identification, replacing fingerprints. Due to its accuracy, DNA profiling in forensics not only has the power to positively identify criminals, but also make sure an innocent person is not wrongly convicted. Moreover, in some cases where the victims are hard to identify, DNA analysis can give these victims an identity (Thelin).
Due to its accessible and hardy nature, samples of DNA are sometimes the only evidence that is available for collection, and combined with its accuracy, make it a very valuable asset in the courtroom. Efforts are constantly underway to improve the efficiency and accuracy of these techniques, but these genetic forensic applications, like any other test, is by no means 100% accurate. These techniques above indeed offer unique supplemental evidence, but I believe more time and work is needed in order to make DNA forensics more invaluable in the courtroom.
This includes expanding current national databases and improving upon existing technology and techniques. There needs to be consideration for the matching of family members such as distant relatives or twins. For example, in January of 2007, a perfect DNA match at 13 regions was discovered in only 30,000 samples (Felch). Forensic DNA analysis does not only play a role in matching a certain individual to a crime, but also can be used to prove innocence also. As a result, though the chance of having a match with a relative or twin may be very small, the risk of human error in laboratories is significantly larger.
Currently, DNA analysis is not completely automated, and human errors can play a huge factor in the validity of DNA evidence. Contamination of samples, which may turn a positive identification into a negative one, is a key problem area in the processing of DNA samples. Furthermore, there have also been cases of planted fake DNA evidence, and the improper or incomplete collection of DNA may also question the validity of the evidence and raise privacy concerns (Pollack). I believe that although genetic evidence can often make a great case, it should always be viewed with skepticism.
If other evidence in the case raises doubts or if the collection and analysis was not error-free, then it should not be taken as definite. The increasing popularity of forensics in media such as TV shows, which often represent DNA profiling and forensic in an oversimplified manner, has given the public a skewed view of real life forensics. If DNA is presented as convincing evidence, then I believe the jury should be informed of the possible risk factors associated with genetic analysis. A convincing case should be made through a combination of evidence, rather than just relying on DNA itself.
As the progress of science and technology continues to reach new heights, there is no doubt that new and more efficient techniques will be developed that may address many of the concerns that current forensic DNA profiling poses today. This is not to say that at its current stage forensic DNA should be taken lightly. However, with lives and innocence at stake, everything, including genetic analysis, should be carefully reviewed and tested thoroughly. As with any relatively new technology, there are certainly going to be issues and roadblocks.
However, forensic DNA profiling is here to stay, and as more work and effort is placed into its research and development, justice will be served to the guilty, keeping criminals in jail and the innocent free.