"DNA Under the Scope, and a Forensic Tool Under a Cloud."

Since the 1970’s scientists have been deciphering DNA for multiple reasons including forensics, cancer biology, archaeology and evolutionary biology. Just recently Dr. Marina Stajic, the previous director of the forensic toxicology lab at the medical examiner’s office in New York City, has filed a lawsuit against NYC, claiming that “she had been forced into retirement last year in part because of a disagreement with her superiors over the accuracy of certain DNA tests.” Following the 1970’s, the tests conducted to decipher DNA have been reformed so that less DNA is required to run the tests. The original chemical process destroyed most of the DNA, making it so that scientists needed a large amount to start off with. Unfortunately, in many cases it is difficult to collect so much genetic material, making the tests impossible to complete. One of the first major improvements was made by biochemist Kary Mullis, who created polymerase chain reaction, or PCR, which allowed scientists to make copies of a gene fragment. Recently, a more “cutting-edge” technique has been used to analyze DNA, called low copy number DNA analysis. This technique requires a very small amount of DNA; just collecting some loose skin cells off of surfaces is sufficient. As low copy number DNA analysis uses such a small amount of genetic material, there are several errors that can be made, making it quite controversial. One issue is the fact that low copy number DNA analysis can detect a mix of DNA from more than one person, DNA that may be irrelevant for situations like crime scenes. Furthermore, it has been proven that people can leave traces of DNA on objects that they haven’t even touched, further jeopardizing the accuracy of low copy number DNA analysis. Another error, called allelic drop-out, occurs when so few DNA molecules are collected that they don’t react with the PCR used to duplicate the DNA. When used in forensics,  this can lead to the creation of a genetic profile that doesn’t even match the crime scene. Overall, low copy number DNA analysis has revolutionized multiple fields of science, but is still considered controversial to use due to the errors that can occur.

Low copy number DNA analysis is definitely relevant to society today. As mentioned before, this DNA analysis technique has improved police work, cancer biology, in vitro fertilization, archaeology and evolutionary biology. Fewer DNA molecules are required, making it easier to analyze DNA in situations in which a large supply of DNA isn’t available, like at a crime scene or when studying cancer cells. Without this type of testing people would have difficulty applying the use of DNA analysis, since not enough DNA would be provided at a crime scene for developing a profile for the case, or on a fossil to classify it. Low copy number DNA analysis is even being used to help identify skeletons and remains of Civil War soldiers. Overall, while it has its faults, low copy number DNA analysis has allowed the impossible to occur in multiple fields.

I found the article very informative and pleasant to read. The topic of DNA analysis and the many techniques used is so intriguing, and it was very interesting to learn about it in the article. The author did a nice job of making the topic clear and easy to understand through giving just enough detail and using vocabulary that is understandable to people who aren’t scientists. The author also included many quotes from scientists and experts, specifically from Dr. Budowle, the executive director of the Institute of Applied Genetics at the University of North Texas Health Science Center, and Stephen R. Quake, a biologist at Stanford University. This allowed me to see that the information was from a reliable source and all the claims that were made by the author could be backed up. The only thing that could have been done better would be the explanation of low copy number DNA analysis. The author did not spend a lot of time explaining what exactly this technique is, what it does, or how it works; the description was pretty vague, considering the entire article was based on this concept. I was able to get a basic level of understanding of low copy number DNA analysis, but it would have been beneficial to provide a more detailed description. However, in the end, I did definitely learn a lot from this article and found it pretty interesting.

Zimmer, Carl. "DNA Under the Scope, and a Forensic Tool Under a Cloud."The New York Times. The New York Times, 26 Feb. 2016. Web. 01 Mar. 2016. <http://www.nytimes.com/2016/02/27/science/dna-under-the-scope-and-a-forensic-tool-under-a-cloud.html?rref=collection%2Fsectioncollection%2Fscience&action=click&contentCollection=science®ion=rank&module=package&version=highlights&contentPlacement=9&pgtype=sectionfront>.