The Role of Forensic DNA Technology in Criminal Cases

1. The Role of Forensic DNA Technology in Criminal Cases Michael J. Spence, Ph.D.

5. WHAT IS DNA? • DEOXYRIBONUCLEIC ACID • DNA is found in all nucleated cells • DNA is the genetic blueprint that encodes your physical appearance • You received half of your DNA from your mother and half from your father.

6. Blood Semen Hair Root Saliva Bone Biological Sources: All nucleated cells. Extraction

7. Samples from sexual assault kits Ski masks Combs Toothbrushes Hat bands Earrings Drink containers Cigarette Butts & Chewing Gum Stamps & Envelopes Weapons Steering wheel of a stolen car OTHER SOURCES OF DNA

8. Obstacles to Recovery Original size of the stain Chemical contaminants Nucleases/Bacteria Sunlight Shear forces

9. CRIME SCENE VICTIM SUSPECT What can DNA tell usabout a crime?

10. Biological material What can DNA tell usabout a crime? Determine the DNA profile Compare each crime scene DNA profile to profiles collected from suspects

11. Slot blots vs. RT-PCR Extract/Purify DNA Biological Material STEPS: DNA PROFILES FROM BIOLOGICAL SOURCES Visualize with Fluorescent Scanner (More Obsolete Technology) Capillary Electrophoresis Amplify using PCR

12. Real-Time PCR-Instrument

13. Real-Time PCR-Results

14. POLYMERASE CHAIN REACTION (PCR)‘molecular Xeroxing’ • The process by which scientists make millions of copies of specific pieces of DNA. • The size of these “Xeroxed DNA fragments” differ from one person to another.

15. Denatured Heat DNA Double Helix Uncoiled

16. Denature Anneal Primers Polymerase Extension Heat ? 2 copies of original template-DNA has doubled! POLYMERASE CHAIN REACTION(PCR) Template DNA Heat Nobel Prize Step

17. 1 cycle 2 cycles 3 cycles 4 cycles ? POLYMERASE CHAIN REACTION(PCR) After 30+ heating/coolingcycles, we have oodles of DNA

18. The Utility of Y-STR DNA Typing • Method allows typing of male DNA, to the exclusion of any female DNA present in a sample • Method targets DNA markers on the • Y-Chromosome • Analysis kit from Promega includes 12 Y-STR loci • This is particularly useful for DNA mixtures observed in sexual assault & child molestation cases

19. Capillary Electrophoresis-Instrument

20. Slot blots vs. RT-PCR Extract/Purify DNA Biological Material STEPS: DNA PROFILES FROM BIOLOGICAL SOURCES Visualize with Fluorescent Scanner (More Obsolete Technology) Capillary Electrophoresis Amplify using PCR

21. Capillary Electrophoresis-Data

22. C O D I S OMBINED NA NDEX YSTEM Indiana Downs?----the Latex Bandit?---- Who drank the Red Bull in Waco on Halloween? Baton Rouge?

23. The Utility of Forensic Mitochondrial DNA (mtDNA) Analysis • Method allows typing of problem samples- degraded DNA, low concentrations, WTC samples • Method targets DNA sequences in what is called the “D-loop”, hyper variable HV1 and HV2 regions • Method identifies various ‘single’ DNA sequence differences between crime scene samples and reference standards from an individual • If there are NO single nucleotide variations, the probability of such a match can be calculated

24. Forensic mtDNA Analysis-Data

25. SO many rules-documentation, lab audits Bad odors,… Dirty diapers,…. Used tampons? Work with blood, fungi, dangerous chemicals Enormous case backlogs, pressure to rush cases Testifying, …..WAITING and WAITING Opinionated pencil-pushers-no scientific instincts DNA/Ancestry: Another internet-based HOAX REASONS WHY I’M HAPPY TO BE OUT OF THE LABORATORY:

26. My Take on Genetic Ancestry Testing

27. Estimated 500,000 ancestry tests since 2001 Australian scientists demanding regulation of internet-based ancestral testing con artists “It’s a complete waste of money, ……the testing tells you almost nothing about your individual ancestry.” Simon Easteal-anthropology expert at the Australian National University in Canberra DNA/Ancestry:Yet another internet-based HOAX

28. Jonathan Marks-anthropology expert at the University of North Carolina-Charlotte: “It sure looks like science. Well, it IS science. It’s done by scientists, it’s done on DNA samples, and it produces real data. That’s the beauty of this scam. The companies aren’t scamming you. They’re not giving you fraudulent information. They are giving you data, REAL data, and allowing you to scam yourself.” The HOAX (continued)

29. Deborah Bolnick-anthropology expert at the University of Texas at Austin: “Claims that this analysis will tell you much about where you came from are downright fraudulent.” The HOAX (continued)

30. Faulty Collection/Packaging of Biological Evidence Faulty Chain of Custody Evidence Examination Priority Decisions on Items Separation of Known Standards from Evidence!! Presumptive vs. Confirmatory Results-Testimony? Timing of Biological Material Deposits-Testimony? DNA Extraction/Purification-Controls PCR: Positive and Negative Controls Interpretation of CE Alleles/Electropherograms Actual source of DNA Profiles Found-Testimony? WHAT CAN GO WRONGWITH A DNA CASE?

31. Interpretation of DNA Mixtures Analyst Case Notes and Disseminations Case Report Wording and Conclusions Population Statistics Contamination, ….Rare Instances of Case Item Tampering: Houston, Derek Rocco Barnabei WHAT CAN GO WRONGWITH A DNA CASE?

32. Sir Alec Jeffreys, Colin Pitchfork, 3000+ tests 212 Innocence Project exonerations nationwide Joseph Castro: Lifecodes, Roberts vs. Lander Crime lab oversight laws-MD, VT, 21 more. Houston Crime Lab Josiah Sutton-Houston Crime Lab George Rodriguez-17 years-Houston Crime Lab James Waller-12 exonerations in Dallas Co. Lynn Dejac-first female DNA exoneration Real Cases, Exonerations:

33. Dwayne Allen Dail-18 years-North Carolina Brewer/Brooks-10-years-PLUS 6 more in jail! Joyce Gilchrist-Pierce, Miller, and McCarty Curtis Edward McCarty-21 years on death row Earl Washington Jr.-innocent with 9 days to live Robin Lovitt-VA Death Row-Discarded evidence Mary Jane Burton-A saint among analysts My first testimony-Oprah? Real Cases, Exonerations:

34. Yellowstone National Park-1966

35. Thermus aquaticus (Taq) Discovered by Thomas Brock Indiana University

36. Thank You.... Questions?