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Forensic DNA Phenotyping for Investigative Leads
This picture is the property of the Genetic Science Learning Center at the University of Utah
Hwan Young Lee, Ph.D.Yonsei University College of Medicine
Involves generation of DNA profiles usually with the same genetic markers and then MATCHING TO REFERENCE SAMPLE
o Forensic cases -- matching suspect with evidence
o Paternity testing -- identifying father
Conventional Forensic DNA Typing
Picture from www.cstl.nist.gov/strbase/NISTpub.htm
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Advanced Forensic DNA analysis
• Human identification testing
• DNA database search
• DNA mass screening
Forensic DNA phenotyping (FDP)
• Ancestry inference
• Externally visible characteristics
• Forensic age estimation
Identification markers Intelligence markers
Slide from the ISFG 2015 workshop presentation by W. Branicki
o Autosomal STRs: multiplex HID kits available
o Y-STRs: HID kits available
o X-STR: HID kits available
o mtDNA: published protocols for CR and complete genomes
o SNPs, INDELs: published protocols
Forensic Human Identification
Slide from the ISFG 2015 workshop presentation by W. Branicki
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o Matching DNA profiles – evidence in favor of hypothesis that two
samples come from the same individual
o Reference DNA samples needed to perform human ID testing
o In many cases suspect is unknown to the investigation
Human Identification Testing
Slide from the ISFG 2015 workshop presentation by W. Branicki
DNA Database Search
Slide from the ISFG 2015 workshop presentation by W. Branicki
12,1428, 30
910
16, 176
11, 1411, 1322, 23
X, Y
12,1428, 30
910
16, 176
11, 1411, 1322, 23
X, Y
DNA profiling
Matching DNA profiles
Evidence DNA profiles Reference DNA profiles
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DNA Mass Screening
Slide from the ISFG 2015 workshop presentation by W. Branicki
o ENFSI report: 439 finished mass screens – 315 successful
o 1998 Germany: rape and murder – 11200 males investigated
o 2001 Poland: 14 rapes and murder – 421 males investigated
Source: Internet
Intelligence Markers
Picture from snapshot.parabon-nanolabs.com
DNA test
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Ancestry Inference
o Lineage markers (mtDNA andY-STR)
o Ancestry Informative Markers (AIMs)
o Single Nucleotide Polymorphisms, INDELs
o Several to several hundreds markers analyzed
o Usually “continental” resolution (East Asia – Europe – Africa)
https://www.sott.net/
Bomber from Morocco (2004)
Madrid Bomber: 34Plex AIM-SNP Assay
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Global AIMs panel v2
Slide from the ISFG 2017 presentation by D. Runa
Pigmentation
Stature
Facial morphology
Hair shape
Myopia
Hair greyingHair distribution
Source: National Portrait Gallery in Canberra
Externally Visible Characteristics
Slide from the ICGSK2016 presentation by W. Branicki
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Eye Color DNA Phenotyping
http://www.erasmusmc.nl/47743/3604975/HIris?lang=en
TTTCCC
Single Nucleotide Polymorphism (SNP) Ind1: CATTTCGCGATInd2: CATTTTGCGAT
Eye and Hair Color DNA Phenotyping
http://www.erasmusmc.nl/47743/3604975/HIris?lang=en
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Forensic Age Estimation
Slide from the ISFG 2015 workshop presentation by W. Branicki
o Information about chronological age of an offender
- Predicted age can be used to narrow down the search range
o Information about biological age of an offender
- Predicted age can improve forensic DNA phenotyping
https://internetmedicine.com/aging-and-nanomedicine/
Age Prediction with DNA Methylation
Hannum et al. Mol Cell (2013)
71 CpGs
GGACAGGGGCGTGGCGCCTGCTMet Met
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Age Prediction in Blood
MAD (Mean Absolute Deviation) from chronological age = 3.9 years
Zbieć-Piekarska et al. Forensic Sci Int Genet (2015)
o 5 CpGs in the genes ELOVL2, C1orf132, TRIM59, KLF14 and FHL2
Regression function: Age = a + b×CpG1 + c×CpG2 + d×CpG3 + …
Age Prediction in Saliva
Hong et al. Forensic Sci Int Genet (2017)
cg18384097 cg00481951 cg19671120 cg14361627 cg08928145cg12757011 cg07547549
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Age Prediction in Semeno Age correlation of the 3 CpGs and predicted versus chronological
ages of 125 semen samples
Rho = 0.882MAD = 5.2 years
Lee et al. Forensic Sci Int Genet (2015)
cg06304190 (TTC7B) cg06979108(NOX4)cg12837463
cg06304190 cg06979108cg12837463
Analysis of a Casework Example
o A stain preliminary positive for semen and saliva o Two men’s mixed STR profile
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Semen age prediction (ppt)
Saliva age prediction (supernatant)
cg06304190 cg06979108cg12837463
cg18384097cg00481951
cg19671120cg14361627
cg08928145cg12757011
cg07547549
Male 1
Male 2
60s
30s
Analysis of a Casework Example
Ethical and Legal Issues in FDP
o FDP is prediction of appearance from forensic samples
o FDP is developed to guide police investigations in cases
without known suspects
o FDP includes forensic use of DNA for investigation, not
in the courtroom
o Benefit and risk analysis will be needed
o Law: Netherlands, Texas..
