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The DNA Information Pathway TrueAllele ® Workshop April, 2013 Leicestershire, United Kingdom Mark W Perlin, PhD, MD, PhD Cybergenetics, Pittsburgh, PA.

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Presentation on theme: "The DNA Information Pathway TrueAllele ® Workshop April, 2013 Leicestershire, United Kingdom Mark W Perlin, PhD, MD, PhD Cybergenetics, Pittsburgh, PA."— Presentation transcript:

1 The DNA Information Pathway TrueAllele ® Workshop April, 2013 Leicestershire, United Kingdom Mark W Perlin, PhD, MD, PhD Cybergenetics, Pittsburgh, PA Cybergenetics ©

2 Identification Known reference Compare Evidence item

3 DNA Identification Evidence genotype Known genotype , 12 LabInfer Compare Evidence item Evidence data

4 cell nucleus chromosomes locus Short Tandem Repeat (STR) genotype 10, 12 alleles Genotype

5 Match Information Prob(evidence matches suspect) Prob(coincidental match) before data (population) after (evidence) 20 = 100% 5% = At the suspect's genotype, identification vs. coincidence?

6 DNA Mixture Data Quantitative peak heights at a locus peak size peak height

7 Peak Thresholds Threshold Under threshold, don't use alleles Allele Pair 7, 7 7, 10 7, 12 7, 14 10, 10 0%10, 12 10, 14 12, 12 12, 14 14, 14 Simplify data for human review

8 Allele Dropout Threshold Under threshold, use alleles anyway Allele Pair 7, 7 7, 10 7, 12 7, 14 10, 10 > 0% 10, 12 10, 14 12, 12 12, 14 14, 14 Conjure phantom peaks

9 DNA Pathway Broken Evidence genotype Known genotype ??? 10, 12 LabInfer Compare Evidence item Evidence data

10 Human Interpretation Issues Evidence call good data inconclusive peaks are too low for them too many contributors to handle potential examination bias Database hit by association, not by match comparison: make false hits restrict upload: lose true hits

11 TrueAllele ® Casework Evidence preserve data information use all peaks, high or low any number of contributors entirely objective, no bias Database hit based on LR match statistic sensitive: find true hits specific: only true hits

12 Validation Studies Perlin MW, Sinelnikov A. An information gap in DNA evidence interpretation. PLoS ONE. 2009;4(12):e8327. Perlin MW, Legler MM, Spencer CE, Smith JL, Allan WP, Belrose JL, Duceman BW. Validating TrueAllele ® DNA mixture interpretation. Journal of Forensic Sciences. 2011;56(6): Perlin MW, Belrose JL, Duceman BW. New York State TrueAllele ® Casework validation study. Journal of Forensic Sciences. 2013;58(6):in press.

13 TrueAllele ® Casework ViewStation User Client Database Server Interpret/Match Expansion Visual User Interface VUIer Software Parallel Processing Computers

14 Separate Mixture Contributors 25%75%

15 Genotype Thorough: consider every possible genotype solution Objective: does not know the comparison genotype Explain the peak pattern Better explanation has a higher likelihood Victim's allele pair Another person's allele pair Allele Pair 7, 7 7, 10 7, 12 7, 14 10, 10 50%10, 12 10, 14 12, 12 12, 14 14, 14

16 DNA Pathway Restored LabInfer Evidence item Evidence data Known genotype 10, 30% 10, 50% 10, 20% 10, 12 Compare Evidence genotype

17 Match Information Preserved Prob(evidence matches suspect) Prob(coincidental match) before data (population) after (evidence) 10 = 50% 5% = At the suspect's genotype, identification vs. coincidence?

18 Massereene Barracks Attack Patrick Azimkar Mark Quinsey Real Irish Republican Army claimed responsibility Homicide victims March 7, 2009 in Antrim, Northern Ireland

19 Abandoned Burned Car

20 Touch DNA Evidence passenger side safety belt buckle cell phone in center console match stick at side of road

21 Data Ambiguity DNA mixture low DNA quantity allele drop out D21D18D8 vWAD3D18D2 FGATH01D18 no DNA visible

22 Much Data, Little Consensus No Match Statistic abc 021 Brian Shivers

23 Combine DNA Evidence a b c a b c a b a c singlespairsall threedata b c a b c 1.1 million 6.04 STR tests 40, ,

24 Explain All the Data TH01 locus 3 times test 1 test 2 test 3

25 Try All Possible Genotypes TH01 locus 3 times test 1 test 2 test 3

26 Evidence Genotype Objective genotype determined solely from the DNA data. Never sees a suspect. 82% 12% 6%

27 DNA Match Statistic How much more does the suspect match the evidence than a random person? Probability(evidence match) Probability(coincidental match) 6x 13% 82%

28 Statistic at 10 Loci A match between the matchstick and Brian Shivers is 1.1 million times more probable than coincidence.

29 Computer's Match Statistics 5.91 trillion 6.01 billion 1.1 million Colin Duffy Brian Shivers

30 Admissibility Ruling I am satisfied that the stage has now been reached in the case of this system where it can be regarded as being reliable and accepted, and I am satisfied that Dr Perlin has given his evidence in a credible and reliable fashion. In the light of these conclusions I can see no basis on which I could properly exercise my discretion … to exclude this evidence, and I therefore admit it in evidence. December 1, 2011 The Honorable Mr. Justice Hart 18 page ruling on TrueAllele, concluding:

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32 World Trade Center Attack September 11, 2001 in New York City, USA al-Qaeda claimed responsibility Over 2,700 victims

33 Identify Victim Remains biological material

34 Identify Missing People biological material personal effects family references

35 Match Biological Material victim remainsmissing people match

36 Damaged Victim Remains

37 Damaged Personal Effects victim remainsmissing people data a b abab bb 1/10 9/10 match

38 Available Family References victim remainsmissing people abab cc acacbcbc? 1/2 genetic match

39 Match Genotypes victim remainsmissing people match

40 TrueAllele in Criminal Trials Court testimony: state federal military foreign Over 100 case reports filed on DNA evidence Crimes: armed robbery child abduction child molestation murder rape terrorism weapons

41 TrueAllele Information Pathway Known Compare Evidence Knowns database Compare Evidence database

42 Magazine Reading Perlin MW. Forensic science in the information age. Forensic Magazine. 2012;9(2): Perlin MW, Galloway J. Computer DNA evidence interpretation in the Real IRA Massereene terrorist attack. Evidence Technology Magazine. 2012;10(3): Perlin MW. Easy reporting of hard DNA: computer comfort in the courtroom. Forensic Magazine. 2012;9(4):32-37.

43 Book Chapters Perlin MW, DNA identification science, in Forensic Sciences, Wecht CH, editor. Albany, NY: LexisNexis ® Matthew Bender ® ; 2012; Chapter 37C. Perlin MW, The Blairsville slaying and the dawn of DNA computing, in Death Needs Answers: The Cold- Blooded Murder of Dr. John Yelenic, Niapas A, New Kensington, PA: Grelin Press, 2012.

44 Human-Computer Partnership Current TrueAllele applications eliminate DNA backlogs reduce forensic costs solve crimes find criminals convict the guilty free the innocent create a safer society Objective, reliable truth-seeking computer solves the DNA mixture problem handles low-copy and degraded DNA provides accurate DNA match statistics automates DNA evidence interpretation

45 More Information Courses Newsletters Newsroom Presentations Publications


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