DNA Testing in Crime Scenes

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DNA, or deoxyribonucleic exists in all living organisms, is self-replicating and gives a person their unique characteristics. No two people have the same matching DNA. There are many different forms of DNA that are tested for situations such as criminal. Bodily fluids, hair follicles and bone tissues are some of the most common types of DNA that is tested in crime labs today. Although the discovery of DNA dates back to 1866 when Gregor Mendel proved the inheritance of factors in pea plants, DNA testing is relatively new and have been the prime factor when solving crimes in general. In 1966, scientists discovered a genetic code that made it possible to predict characteristics by studying DNA. This lead to genetic engineering and genetic counseling. In 1980, Organ was the first to have a conviction based off DNA fingerprinting and DNA testing in forensics cases became famous in 1995 during the O.J. Simpson trial (SMC History , 2011). DNA analysis is a scientific process among the newest and most sophisicated of techniques used to test for genetic disorders, which involves direct examination of the DNA molecule itself (Lyman, 2014) . Today crime labs use mtDNA analysis. This type of analysis allows smaller degraded pieces of DNA to still be successfully tested (Lyman, 2014) . There are several steps taken when analyzing DNA in forensics. When testing scientists must first isolate the DNA so it is not contaminated and can't be used. Lab technicians the take small pieces of the DNA, conserving as much as they can encase they need to test again. Once testing is done the next step is determining the DNA test results and finally there is the comparison and interpretation of the test results from the unknown and known samples to determ... ... middle of paper ... ...'t show that it was of the victims. The court ruled that extensive discovery requirements for future proceedings, including copies of lab results and reports; explanation of statistical calculations; explanations of any observed contaminants; and chain of custody documents (PBS, 1996) . These recommendations where soon expanded in the Minnesota Supreme Court case Schwartz v. State. Works Cited SMC History (2011).On the human genome project. Retrieved from http://homepage.smc.edu/hgp/history.htm Lyman, M. (2014).Criminal investigation the art and the science. (7th ed.). New Jersy: Pearson USA.Gov. (2012, 08 09).Dna evidence: Basics of analyzing. Retrieved from http://www.nij.gov/topics/forensics/evidence/dna/basics/pages/analyzing.aspx PBS. (1996).The dna "wars" are over. Retrieved from http://www.pbs.org/wgbh/pages/frontline/shows/case/revolution/wars.html

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