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Forensic DNA Past, Present, Future Kathy Sullivan Illinois State Police Joliet Forensic Science Laboratory
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Case Study: Jeffrey Knight Homicide from Kankakee County in December, 1997 A head, hands and feet were found in a garbage bag in the woods Jeffrey Knight was suspected of killing his step mother, Marguerite, and disposing of her partially dismembered body
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Case Study: Jeffrey Knight Screening results: many blood stains found, but only some were human DNA results: performed using DQ-alpha/Polymarker and D1S80
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Case Study: Jeffrey Knight Stains found around the barn, on a reciprocating saw and the trunk and floorboard of a car match Marguerite Knight Random match probability is 2.1 billion Blacks, 5.4 million Hispanics and 5.3 million Whites Jeffrey Knight was convicted and sentenced to 60 years in prison (he is eligible for parole December 2027)
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Case Study: Timothy Evans Summer of 2002 A series of night-time home invasions and sexual assaults begins in Joliet and Bolingbrook Media names the assailant the “Nightcrawler”
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Case Study: Timothy Evans Evidence from one of the “Nightcrawler” sexual assaults is received by the lab in May 2003 Underpants of the young victim are submitted to be tested for biological fluids (semen and saliva)
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Case Study: Timothy Evans Testing indictes saliva on the crotch lining and the stain is removed for DNA analysis
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Case Study: Timothy Evans DNA analysis yields a mixture of profiles consistent with the victim and one additional male contributor
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Case Study: Timothy Evans Minor male DNA profile is entered into the DNA Index June 11, 2003 a match is reported to a sample from an Aurora case two years before The matching sample is a standard from Timothy Evans
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Case Study: Timothy Evans Joliet Police Department is notified and on June 14 th the suspect is arrested Confirmatory analysis verifies the match Random match probability of 1 in 20 billion Blacks, 1 in 310 billion Hispanics and 1 in 330 billion Whites
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Case Study: Timothy Evans 15,17 19,21 X,Y14,1529,30 15,16 11,13 12,129,11
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Case Study: Timothy Evans X,Y 15,17 9,11 6,79,99,10 9,11
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Case Study: Timothy Evans Timothy Evans pleaded guilty to the charges against him and was sentenced to 50 years in prison The DNA evidence and CODIS hit were instrumental in providing law enforcement with the link to the assailant
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Advances in DNA Technologies Yield Gel = how much DNA? QuantiBlot = how much is human?
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Advances in DNA Technologies Quantification Procedure Tells how much human DNA AND how much male DNA is in the sample
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Advances in DNA Technologies RFLP
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Advances in DNA Technologies RFLP PCR: –D1S80
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Advances in DNA Technologies RFLP PCR: –D1S80 –DQ-alpha –Polymarker
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Advances in DNA Technologies RFLP PCR: –D1S80 –DQ-alpha –Polymarker –STRs
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Advances in DNA Technologies RFLP PCR: –D1S80 –DQ-alpha –Polymarker –STRs –Y-STRs
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Additional Technologies Mitochondrial DNA
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On the Horizon Larger STR multiplexes
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On the Horizon Larger STR multiplexes Automation – fluid handling systems
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On the Horizon Larger STR multiplexes Automation – fluid handling systems High-throughput detection systems
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On the Horizon Larger STR multiplexes Automation – fluid handling systems High-throughput detection systems Accreditation
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Forensic DNA Past, Present, Future Kathy Sullivan Joliet Forensic Science Lab 515 E. Woodruff Road Joliet, Illinois 60432 815-740-3543 Katherine_Sullivan@isp.state.il.us
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