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In Forensic Criminology. MH SBI 4U. ( DNA) Deoxyribonucleic acid. DNA is thought of as a “recipe for life” DNA is the nucleic acid that contains the genetic instructions that bring us to life Found in the nucleus of every cell in the human body Four bases: A, T, C, G
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In Forensic Criminology MH SBI 4U
(DNA) Deoxyribonucleic acid • DNA is thought of as a “recipe for life” • DNA is the nucleic acid that contains the genetic instructions that bring us to life • Found in the nucleus of every cell in the human body • Four bases: A, T, C, G • Our DNA is 99.9% identical • 0.1 % is different, 3 million base pairs
Dr. Alec Jeffreys • Dr. Jeffreys discovered the use of DNA in forensics • Fingerprinting was the first method of evidence • Searched for a more accurate method • DNA in forensic criminology is the use of DNA to match a criminal to a crime scene • Which was powerful enough to implicate or eliminate a suspect
Southern Hybridization Method • Extracted DNA from evidence is compared to DNA extracted from reference samples • Electrophoresis • Negatively charged DNAs migrate towards the positive electrode • Smaller DNA fragments move faster • Transferred to a nylon membrane (like paper) • A single locus probe is a DNA or RNA sequence that is able to hybridize with DNA from a specific restriction fragmentation • Single locus probes are usually tagged with a radioactive label for easy detection A relative’s DNA can be used if there is no body to be analyzed
We can extract DNA from almost everything • Blood • Hair • Semen • Saliva • Skin • We call this evidence “trace evidence” • “May” be enough evidence to put someone away (Ex. taxi)
Murder at Rodman Dam, 1988 • In July 1987, Randall Scott Jones and Chris Reesh were target shooting (with .3-30 rifles) • Truck got stuck in a sandpit • Found a couple sleeping in their truck, Matthew Brock and Kelly Lynn Perry • They ended up driving away with both trucks • What happened? Matthew and Kelly were shot..
Bodies were found in a nearby forest (both shot) • Kelly appeared to have been sexually abused • Warrant was issued by court • Confessed as soon as the DNA results were announced
DNA Databases 2 Types • First Type: Known DNA • Second Type: Unknown DNA
Wrongfully Accused • Worked on freeing the wrongfully accused • Many were set free • Saved from the death penalty • Various speeches all over the internet
Pig Experiment • Used to train forensic scientists who get involved right away • Pigs have similar skin to a human • Used to build their knowledge on the insects that decompose a body
Conclusion • Using DNA in forensic criminology has helped the justice system greatly • Has sent/taken people to/from prison • DNA lasts forever • We can improve on the time it takes to analyze DNA
References • _____. (1999). Forensic DNA. Retrieved from: http://library.thinkquest.org/28599/courtroom.htm • Human Genome Project Information. (2009). DNA Forensics. Retrieved from: http://www.ornl.gov/sci/techresources/Human_Genome/elsi/forensics.shtml • Nute, Dale. (1999). Advice about a Career in Forensic Science. Retrieved from: htpps://www.criminology.fsu.edu/faculty/nute/FScareers.html • William C. Thompson. (2008). The Potential for Error in Forensic DNA Testing (and How That • Complicates the Use of DNA Databases for Criminal Identification). Retrieved from: http://www.councilforresponsiblegenetics.org/pageDocuments/H4T5EOYUZI.pdf • _____. (2010). Forensic DNA analysis in the identification of human • remains in mass graves. Retrieved from: http://academicjournals.org/JCPFM/PDF/Pdf2010/Mar/Jakovski et al.pdf • Advancing Criminal Justice Through DNA Technology. (2010). History of Forensic DNA Analysis. Retrieved from: http://www.dna.gov/basics/analysishistory • _____. (2008). Has DNA testing led to significant improvements in the criminal justice system?. Retrieved from: http://deathpenalty.procon.org/view.answers.php?questionID=001189 • CBC News Canada. (2010). Key events in the Bernardo/Homolka Case. Retrieved from: http://www.cbc.ca/news/canada/story/2010/06/16/f-bernardo-homolka-timeline.html • National Criminal Justice Reference Service. (2003). Forensic Science. Retrieved from: http://www.policyalmanac.org/crime/archive/forensic_science.shtml • Cold Spring Harbor Laboratory. (2003). State of Florida vs. Jones and Reesh, Murder at Rodman Dam, 1988. Retrieved from: http://www.dnai.org/d/index.html?m=1,3 • Federal Bureau of Investigation. (2007). Combined DNA Index System (CODIS). Retrieved from: http://www.fbi.gov/about-us/lab/codis • _____. (2001). What is DNA?. Retrieved from: http://www.ojp.usdoj.gov/ovc/publications/bulletins/dna_4_2001/dna2_4_01.html • The Biology Project. (1996). DNA Forensics Problem Set 1. Retrieved from: http://www.biology.arizona.edu/human_bio/problem_sets/DNA_forensics_1/01t.html • Detective Ray Rikic ( Head of the Hamilton Forensics Police Department)
Sites for Pictures • http://www.molecularstation.com/images/southern-blot.jpg • http://farm1.static.flickr.com/69/205471921_05b52359f6.jpg • http://evolution.berkeley.edu/evolibrary/images/news/dnafingerprints.gif • http://3.bp.blogspot.com/_6WSTYpSuKf0/SwxRK03FeWI/AAAAAAAAABw/ON7EJC816Cs/s1600/SCANNER.jpg • http://3.bp.blogspot.com/_DAgs4uhkNSE/SSH4bh9l6_I/AAAAAAAAABs/M_hpUBCtNRw/s400/DNA+01.jpg • http://bernews.com/wp-content/uploads/2010/08/dna_crime.jpg • http://www.newsnet14.com/images/Codis.jpg • http://www2.fbi.gov/hq/lab/lab2006/images/investigations2.jpg • http://merahjinggabiru.files.wordpress.com/2012/01/question-mark.jpg • http://www.uwindsor.ca/dailynews/2011-10-13/pig-experiment-chance-to-share-forensic-knowledge-with-windsor-police-officers • http://www.gamepimpin.com/content/icons/csi-icon-1.jpg • http://www.georgetandy.com/evidence_low_resolution-blk-alpha.jpg