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Technology Transfer Workshop Application of Laser Microdissection (LMD) to Expedite Forensic Sexual Assault Casework Kelli Raley, MSFS North Louisiana Criminalistics Laboratory Shreveport, LA NFSTC Laser Microdissection Workshop, 2007
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Technology Transfer Workshop LMD Microscopy Research and Experience: Highlights Why LMD for North Louisiana Crime Lab (NLCL) Casework? Elimination of Manual Extraction Reproducibility/Sensitivity Troubleshooting Single Amplification/Optimization Absence of Sperm LMD: Streamlined, Novel Process
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Technology Transfer Workshop Leica™ LMD Microscope
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Technology Transfer Workshop Why Laser Microdissection? ~45% of all NLCL DNA cases involve sexual offense so Need to eliminate bottleneck in DNA analysis
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Technology Transfer Workshop Disadvantages of LMD Initial cost Novel validation ~$4.25 each for PEN slides PEN foil contains pores ≈ sperm –PEN slides are Leica™ product Except for PEN slides, no other consumables for Leica
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Technology Transfer Workshop Advantages of LMD Eliminate traditional extraction Absolute separation of sperm and epithelial DNA Effect of traditional PCR challenges minimized Decrease analysis time for a sexual assault sample
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Technology Transfer Workshop Elimination of Traditional Extraction 1.Direct amplification after LMD?
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Technology Transfer Workshop Elimination of Traditional Extraction 1.Direct amplification after LMD? 2.Pre-amplification Lysis –Constraints Can’t adversely affect PCR Limited volume ( 10µL) Lyse-N-Go™ PCR Reagent (LNG) 25µL reaction vs. 50µL Recombinant Proteinase K
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Technology Transfer Workshop Comparison of Pre- Amplification Treatments 150 sperm 25µL volume Profiler Plus 30 PCR cycles
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Technology Transfer Workshop Pre-amplification Lysis: ProK/DTT Cut directly into water Recombinant ProK Lysis incubation in TC PCR reaction components to same tube Amplify, analyze
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Technology Transfer Workshop Additional Experiments: Sensitivity PCR cycles amplification reaction volume with reduced volume PCR ( RVPCR) –15µL, 10µL PCR with fewer sperm for lowest detection limit
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Technology Transfer Workshop ProK/DTT 150 sperm, 30 cycles 25µL 15µL 10µL Avg PH ~880 RFUs Avg PH ~948 RFUs Avg PH ~2540 RFUs
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Technology Transfer Workshop Reproducibility Profiler Plus 30 PCR cycles
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Technology Transfer Workshop ProK/DTT 100 sperm, 30 cycles 25µL 10µL Avg PH ~157 RFUs Avg PH ~2631 RFUs drop-out
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Technology Transfer Workshop ProK/DTT 50 sperm, 30 cycles drop-out 25µL 10µL Avg PH ~174 RFUs Avg PH ~556 RFUs
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Technology Transfer Workshop Elimination of traditional extraction possible Absolute separation of sperm and epithelial DNA possible LMD together with Pre-amplification Lysis:
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Technology Transfer Workshop Profiler Plus Exciting! 50 sperm, 30 cycles, 10µL
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Technology Transfer Workshop 50 epi nuclei, 30 cycles, 10µL drop-out Profiler Plus
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Technology Transfer Workshop 25 epi nuclei, 30 cycles, 10µL drop-out Profiler Plus
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Technology Transfer Workshop Early NLCL Research for LMD: Summary Replace DNA extraction and purification with novel pre-amplification lysis Physical and complete separation of sperm and epithelial DNA RVPCR, 30 cycles, reproducible Sensitivity: 50-150 sperm http://www.promega.com/geneticidproc/ussym p16proc/abstracts/langley.pdf
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Technology Transfer Workshop From Research to Validation... Troubleshooting Identifiler for single amplification How many sperm? No sperm observed
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Technology Transfer Workshop Troubleshooting Static –humidity –cuttings into 25µL vs 50µL Electropherogram Conundrum –“dye-saturated” e-grams, Contamination? Non-specific binding? –Profiler Plus vs. Profiler vs. Identifiler
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Technology Transfer Workshop Profiler Plus Exciting! 50 sperm, 30 cycles, 10µL
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Technology Transfer Workshop Electropherogram Conundrum
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Technology Transfer Workshop drop out 24/29 50 sperm, Identifiler, 30 cycles
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Technology Transfer Workshop From Research to Validation... Troubleshooting Identifiler for single amplification How many sperm? No sperm observed
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Technology Transfer Workshop Identifiler Optimization TE -4 vs DepC H 2 O –Vary Tris, pH 8.0 in TE -4 : normal, 1/2x, 1/4x, 1/5x PCR cycling –28+6, 20+14, 20+10 cycles –31 cycles MgCl 2 –Vary extra Mg 2+ added –0.5mM – 1.5mM still optimal for RVPCR
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Technology Transfer Workshop 29/29 alleles Identifiler Optimization
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Technology Transfer Workshop Electropherogram Conundrum
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Technology Transfer Workshop 1/4x Tris in TE -4 Solved?
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Technology Transfer Workshop 1/5x Tris in TE -4 Don’t let TE -4 sit around! Electropherogram Conundrum Solved? Lesson..
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Technology Transfer Workshop From Research to Validation... Troubleshooting Identifiler for single amplification How many sperm? No sperm observed
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Technology Transfer Workshop 29/29 alleles 50 sperm, Identifiler
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Technology Transfer Workshop 25 sperm, Identifiler 23/29
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Technology Transfer Workshop 15 sperm, Identifiler 20/29
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Technology Transfer Workshop From Research to Validation... Troubleshooting Identifiler for single amplification How many sperm? No sperm observed
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Technology Transfer Workshop No sperm observed Cut spot from PEN slide Organic extraction –Qiagen EZ1? YSTR and STR panels
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Technology Transfer Workshop SGM Plus results, foil cut-out 1:20 male:female epithelia
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Technology Transfer Workshop YSTR results, foil cut-out 1:20 male:female epithelia
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Technology Transfer Workshop Advantages of LMD Eliminate traditional extraction Absolute separation of sperm and epithelial DNA Effect of traditional PCR challenges minimized Decrease analysis time for a sexual assault sample through novel process
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Technology Transfer Workshop Advantages of LMD Effect of traditional PCR challenges minimized –Simplify mixtures, simplifying interpretation –Difficult statistical interpretations eliminated –Less tendency for contaminants/inhibitors? –Increase PCR cycles to enhance LCN sperm analysis
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Technology Transfer Workshop Novel Process The NLCL DNA section envisions a new way of processing and storing sexual assault samples
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Technology Transfer Workshop Novel Process Prepare slide Examine using microscope (+) sperm identification: proceed with LMD, lysis, & RVPCR (-) sperm identification: excise entire spot, proceed with traditional extraction –ample extract for YSTR and STR testing
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Technology Transfer Workshop Cellular Extraction Epithelial Digestion Cell Dissection Pre-amp Digestion Purification Quantification Amplification Supernatant: AP, P30 Pellet: sperm ID (~25-30uL) Sperm Epi Cut 50 sperm ~ 15 min same tube Novel Process
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Technology Transfer Workshop Sexual Assault Sample Processing Time - LMD 1.Presumptive testing (AP, PSA), slide preparation 2.Examine for sperm, cut nuclear material 3.Drying of TE -4 4.Pre-amp (in TC) 5.PCR and gel 2 hours (1hr shake) 15 min -1 hour 45 min overnight (3.5 hrs) 1 day
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Technology Transfer Workshop Improves and streamlines the analysis of sexual assault evidence AND Frees up analyst time! LMD Coupled With Pre-amplification Lysis.....
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Technology Transfer Workshop Current Considerations Shorten lysis time of LMD harvested cells Mixture Studies –Epithelial nuclei, still necessary Non-probative samples Considerations for casework implementation
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Technology Transfer Workshop Acknowledgements Pat Woijkiewicz, Ph.D. NLCL DNA staff Christine Sanders Rosalind Franklin University of Medicine and Science Andy Lee Leica™ Microsystems
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Technology Transfer Workshop Contact Information Kelli Raley North Louisiana Criminalistics Laboratory 1115 Brooks St Shreveport, LA 71101 (318)-227-2889 kraley@nlcl.org
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