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Science Direct Essay In the Science Direct (2006) article â€Å"The Last King: A royal maternity case solved by ancient DNA analysis† the author’s Jorgan Dissing, Jonas Binladen, Anders Hansen, Birgitte Sejrsen, Eske Willerslev and Niels Lynnerup informs the reader about the last Danish Viking Kings, Sven Estriden who died in A.D. 1074 and was entombed in the Roskilde Cathedral. The problem on hand and what the author’s make an attempt to reveal is whether or not Sven Estriden’s mother, Estrid was entombed in the pillar across the chancel, as there have been many doubts among historians whether the woman was indeed Estrid or someone else. To find whether Estrin was the actual mother, the author’s used variety of different tests and methods. The analysis done by these proficient authors included, DNA extraction methods and examination of skeletons while taking the most special care to ensure nothing got damaged proving that the woman buried was not Sven’s mother. The ‘Last Viking King’ is written by a number of authors who have very prestigious academic backgrounds. There is in fact, no doubt that there is no shortage of professionals represented in regard to this scientific endeavor. Within this article the reader is given the academic departments that the authors are associated with; Jorgen Dissing is associated with the Research Laboratory, Jonas Binladen in the Department of Evolutionary Biology, Anders Hansen is associated with the Department of Evolutionary Biology and Department of Forensic Pathology, Birgitte Sejrsen is associated with the Department of Forensic Pathology, Eske Willersley the Center for Evolutionary Genetics and last but not least Niels Lynnerup who is affiliated with the Antrophological Laboratory. Between these authors, four are from the Institute of Forensic Medicine, one author is from the Biological Institute and the last author is from the Niels Bohr Institute. All six author’s are from the University of Copenhagen located in Denmark, which has produced 8 Noble Prize winners and the university itself has been ranked 44th in the world. (University of Copenhagen, 2012) With such variation of researchers in different fields the author’s worked in, it may have been reasonable to find some researcher’s from another university to contribute and also have actual author’s who had worked in the area of writing to help out. By no means do these authors fall short in terms of their qualifications and areas of expertise and one can only be reassured these author’s were more than certified in doing this study, but in terms of writing the article may have been more appealing if one of the author’s had a background history in writing. In order to answer the question â€Å"Was the individual in the tomb indeed Sven’s mother Estrid?† the author’s used different methods that included extracting DNA, and examining skeletons to help them on their quest to find the answer. The first method consisted of extracting DNA from tooth samples. In order to do extraction of DNA, most methods are designed to deal with fresh tissues containing high molecular weight DNA and intact cells. (Nature Publishing Group, 2007) In ancient specimens there is usually no cell structure that are preserved due to extraordinary time periods the specimen has gone through. (Nature Publishing Group, 2007) So incases of ancient DNA extraction bone and teeth samples may be used to help extract potential DNA. In the case of this article, two teeth, the cannies and premolars, were extracted from both King Sven’s skull, and two from the skull perceived to be Sven’s mother Estrid. The researchers methods of extracted DNA came from their tooth samples, by using one tooth at a time. Some of the main stages the tooth went through included; being cleaned with a paper clutch soaked in 10% commercial bleach and UV-irradiated for 20 minutes on each side. Then the surface of the tooth was sealed by the application of two layers of cellulose lacquer. From there the root was cut horizontally around 5 millimeter from the root/crown, junction where then the surface area that was exposed by UV irradiated for 20 min. Next a dental drill was used to remove the pulp. The DNA was extracted using the dialysis approach of Kolman and Tuross. (Binladen, Dissing, Hansen, Lynnerup, Sejrsen Willersley, 2006, p.23) A second tooth was used for replication of key D-loop but the study was done in a separate laboratory and by only three of the authors; Anders Hansen, Eske Willersley and Jonas Binlanden. (Binladen, Hansen, Willersley, 2006, p.23) The author’s logical approach of Extracting DNA included using the samples of teeth from both specimens as the evidence is shown in the article. The author’s do a good job leading you on a path that depicts step-by-step process of how the authors extracted the DNA from the tooth samples. This second method used to find out whether if Estred was the mother buried in the tomb the author’s conducted an examination of Estrid’s skeleton to attempt an mtDNA analysis of the remains. MtDNA other wise known as mitochondria DNA is passed down from their mothers to their sons and daughters. MtDNA tests are a good way to test your direct maternal lineage. (Genetic Home Reference, 2012) In this research If the women in the tomb was in fact Estred’s mother, the mtDNA sequence should have been exactly the same, as mothers pass it down to their children, which would mean it would have been inherited by the son Sven. In the research the author’s found â€Å" that mtDNA from Sven and Estrid differs at two nucleotide positions makes maternal kinship between the two highly unlikely.† (Binladen Et al, 2006 p.26) On top of doing mtDNA test’s the authors also did physical anthropological examination of the skeletal remain of the women, they came to realize the individual was no more than 30 – 40 years old at the time of their death. This makes it impossible for the individual in the tomb to be Sven’s mother, considering historic facts state the mother passed away during the age of 70. The second thing the author’s realized was when they did the same process mentioned above with Svens remains there results showed the age of death for sven was 40 – 60 years old which fall according to historic records that state Sven was around 55 years of age at the time of his passing. These tests do a good job of showing you evidence of the fact that the individual in the tomb couldn’t have been Sven’s mother due to the age restrictions. The researchers did the test in the correct way taking mtDNA of both the mother and the son remains examining both to find compelling evidence if there was a match between the two. All though these tests show you with the most accurate depictions of whether the individual in the tomb was indeed the mother. When dealing with work that involves the analysis of DNA, a number of precautions have to be taken into account during your research. First of you have to provide safety for your researchers, often times when your dealing with ancient DNA it is almost guaranteed you will be working with some type of chemicals that can cause skin irritation if you don’t use gloves, more specific chemicals that you work with, can do a lot more significant damage, like severely burn your skin. Another precaution to take is to be careful of the tool’s you’ll be working with, this may include sharp cutting tools and drills, which can also cause severe body injury if not used with the proper safety equipment, like gloves and protective eyewear. Aside from the safety of the workers, a number of precautions have to be taken also to ensure the ancient specimens your associating yourselves with don’t get damaged. Everything from what type of equipment you handle your specimens with, to the room temperature you leave your specimens in play a vital role in making sure nothing gets damaged or wrecked. The researchers from the very start did a good job of respecting their ancient specimens by taking every essential step necessary to protect the specimens. In the beginning when authors Jonas Binladen And Niels Lynnerup retrieved the skeletons from the pillars â€Å"full body suits, facemasks and sterile gloves were worn throughout.† (Binladen Et al, 2006 p.22) Another example can of taking extensive measures to care for the specimen can be seen by the laboratory’s being altered to suite the specimens needs â€Å"The laboratory is fitted out with positive, filtered airflow, hanging UV – lights for sterilization of surfaces.† (Binladen Et al, 2006 p.23) Another example of making sure the specimen was damaged by equipment or by the lab it was in â€Å"all equipment to be used in the lab was sterilized, metal tools and glassware by baking at 250 degree Celsius for 24 hr, other equipment by wiping the surfaces with a cloth soaked with 10% bleach.† (Binl aden Et al, 2006 p.23) In addition to sterilizing the labs and equipment the best chemicals were used for this study â€Å"All chemicals and reagents were of analytical grade or the highest purity available† (Binladen Et al, 2006 p.22) To ensure their perseverance of the specimens the authors even at the end restored the teeth back into the skull â€Å"Subsequently, the teeth were restored by removing the lacquer with acetone, the tip of the root was glued into place, and the teeth were replaced in the skulls.† (Binladen Et al, 2006 p.23) Based on the measurements done by the researchers to ensure the specimens wouldn’t get damaged they did a absolute amazing job. From cleaning out the labs and equipment they used to choosing the best chemicals needed you could tell in a instant that the number one objective besides finding the answer’s, was to not damage any of the actual ancient specimens. Staff workers even made the commitment of coming directly to the laboratory from home. â€Å"staff workers that worked in the laboratory came directly from home and were equipped with full body suits, hairnets, filtered – containing facemasks, and gloves.† (Binladen Et al, 2006 p.23) In conclusion, there was a sense of legitimacy to the methods the authors used in finding out their answers, from DNA extraction’s and skeleton examinations. The authors did a successful job in convincing the reader with clear evidence from their results that concluded the individual in the tomb was too young to be Sven’s mother according to historic records. Overall this article doesn’t inform you whom the real individual found buried next to Sven is, but it does leave you with some opinions that the women may have been one of Sven’s daughters in law. To further reinstate this fact, the reader is told both daughters in laws were queens and had the same name of, Estrid. Ultimately, the full identity of the individual in the tomb is still not evident, the only thing that is supported is the fact it was highly unlikely that Sven’s mother Estrid was the individual entombed. References Dissing, Jorgen, Jonas Binladen, Anders Hansen, Birgitte Sejrsen, Eske Willersley, and Niels Lynnerup. The Last Viking King: A Royal Maternity Case Solved by Ancient DNA Analysis. (2006): 21-27. Print. Jones, Cheryl. Researchers to Drill for Ancient DNA in hobbit Tooth: Scientific American. Researchers to Drill for Ancient DNA in hobbit Tooth: Scientific American. N.p., 5 Jan. 2011. Web. 15 Nov. 2012. Mitochondrial DNA. Genetics Home Reference. N.p., Oct. 2012. Web. 15 Nov. 2012. Nature.com. Nature Publishing Group, 12 July 2007. Web. 15 Nov. 2012. Powell, Kimberly. MtDNA Testing for Genealogy. About.com Genealogy. N.p., n.d. Web. 15 Nov. 2012. University of Copenhagen. Topuniversities. N.p., n.d. Web. 15 Nov. 2012.