dna phenotyping and kinship determination · forensic applications of dna phenotyping predict a...

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© 2015 Parabon NanoLabs, Inc. All rights reserved. DNA Phenotyping and Kinship Determination ©2015 Parabon NanoLabs Inc All rights reserved Ellen McRae Greytak, PhD Director of Bioinformatics Parabon NanoLabs, Inc.

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Page 1: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

© 2015 Parabon NanoLabs, Inc. All rights reserved.

DNA Phenotyping and Kinship Determination

© 2015 Parabon NanoLabs Inc All rights reserved

Ellen McRae Greytak, PhD

Director of Bioinformatics Parabon NanoLabs, Inc.

Page 2: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Forensic Applications of DNA Phenotyping

Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA

Generate investigative leads when DNA doesn’t match a database (e.g., CODIS) Gain additional information (e.g., pigmentation, detailed ancestry) about unidentified remains Main value is in excluding non-matching individuals to help narrow a suspect list �  Without information on age, weight, lifestyle, etc.,

phenotyping currently is not targeted toward individual identification

Page 3: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Snapshot Workflow

D N A P H E N O T Y P I N G ™

� Generate Leads

� Exclude Suspects

� Identify Remains

Hair Color Eye Color Skin Color Freckling

Face Shape Ancestry Kinship

DNA Crime Lab

DNA Service Labs

�������������������� ������� ������� ��� �� � � �� ���� ���������������� � ���� ���������� ������� ����������� ���� ����� ����� � ���� ��

DNA Evidence — or — Extracted DNA

DNA Evidence Is Collected and

Sent to Crime Lab

Crime Lab Extracts DNA And Produces STR Profile (a.k.a. “DNA Fingerprint”)

STR Profile Checked Against DNA Database(s)

Unidentified DNA Is Sent To Service Lab (DNA Extracted If Needed)

No

Yes

Investigator Uses Snapshot Report To:

Parabon Analyzes Genotype Data

���������������������������

�������������������������������������

NOTE: STR Profiles Do Not Contain Sufficient Genetic Information to Produce A SNP Genotype

P b A l

Parabon NanoLabs

Workflow of a Parabon® Snapshot™ Investigation

© 2015 Parabon NanoLabs, Inc. All Rights Reserved. Ready To Learn More? Contact Us For A Free Consultation: http://Parabon-NanoLabs.com/Snapshot

DNA Evidence

Parabon Predicts Physical Traits and Produces Snapshot Report

Genotyping Lab Produces SNP Profile (a.k.a. “DNA Blueprint”)

Genotype Data Is Sent To Parabon

Snapshot Composite Ordered

Is

S

CAAA

P ���

Unidentified Remains

Extracted DNA

���������������������� � ������

�������������������������������������������������������������������������������������� �������������������������������������

��������������������������������������������

Match Found?

50pg – 2ng

Page 4: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

America

Oceania

East Asia

Central Asia

Europe

Middle East

Africa

Ancestry Inference Real results from an unknown individual given to us during a blind evaluation

23% Native American ancestry

17% European ancestry

52% East Asian ancestry

Page 5: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Regional Ancestry Inference

Conclusion: This individual is half Japanese and half Latino

0%

20%

40%

60%

80%

100% East Asia

Southeast

Polynesia

North

Japan

Central

0%

20%

40%

60%

80%

100% America

South North Central Brazil

0%

20%

40%

60%

80%

100% Europe

Southwest Southeast South Northwest Northeast East Central-West Central-East Caucasus

Page 6: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Data Mining: Association Testing Use data mining of genotype+phenotype (G+P) data to identify those SNPs that have the strongest predictive power for phenotype

Subject Eye Color

SNP1 Genotype

SNP2 Genotype

SNP3 Genotype

SNP4 Genotype � SNP1,000,000

Genotype

1 Blue A/G C/C A/A G/G � T/T

2 Green A/A T/T A/G A/G � T/T

3 Hazel G/G C/T G/G A/A � T/T

4 Brown A/A T/T G/G G/G � C/T

3,000 Blue G/G T/T A/A G/G � C/T

Page 7: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Data Mining: Interaction Analysis Single SNP association testing may not capture the whole story Many traits are influenced not only by individual SNPs but by non-additive (epistatic) interactions among SNPs

Ritchie et al. 2001 – AJHG 69:138-147

Page 8: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Interaction Analysis Looking for high-order interactions (>2 SNPs) on a genome-wide scale results in a combinatorial explosion of possible models �  8,333,250,000,000,000,000,000,000,000 (1027)

possible 5-way interactions among 1 million SNPs

�  Currently impossible to exhaust this search space

Parabon has developed software that uses a distributed evolutionary search algorithm to explore the massive space of possible interactions Allows us to discover previously-unknown SNP associations

Page 9: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Predictive Modeling Combine discovered SNPs into a machine learning model that can be used for prediction on new samples Entire mining and modeling process is wrapped in a cross-validation framework, which allows direct calculation of out-of-sample accuracy

Page 10: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Prediction Results – Eye Color Predicted Value = 1.638

Green (61% confidence) Green or Blue (79.4% confidence) NOT Brown or Black (99.3% confidence)

0% 100%

12

34

5

True Eye Color

Pre

dict

ed V

alue

s

Blue Green Hazel Brown Black

1.638

Eye Color

7.4% % 777.4%

Page 11: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Prediction Results – Skin Color Predicted Value = 1.687

Very Fair (78% confidence) Very Fair or Fair (97.1% confidence) NOT Light Olive, Dark Olive, or Dark (97.1% confidence)

0% 100% 6.9%

12

34

5

True Skin Color

Pre

dict

ed V

alue

s

Very Fair Fair Light Olive Dark Olive Dark

1.687

Skin Color

Page 12: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Prediction Results – Hair Color Predicted Value = 2.560

Blond (15.2% confidence) Blond or Red (99.6% confidence) NOT Brown or Black (99.6% confidence)

0% 100% 15.4%

1.0

1.5

2.0

2.5

3.0

3.5

4.0

True Hair Color

Pre

dict

ed V

alue

s

Red Blond Brown Black

2.56

Hair Color

Page 13: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Prediction Results – Face Shape Compare the Predicted Face Shape for this

individual to the Average Predicted Face Shape for subjects with the same sex and ancestry +

X: narrower jaw and chin; wider brow

Y: long face – higher eyes,

nose, and jaw; longer chin

Z: more prominent nose, mouth, and

upper cheekbones; less prominent chin

and cheeks

rower d chin;

Y: long face – higher eyes

Z: more prominentnose mouth andZX: narr

w andjawrd

Page 14: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Prediction Results - Composite Apply predicted pigmentation to predicted face shape

Page 15: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Predicted vs. Actual

Page 16: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Hong Kong Cleanup

Page 17: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Snapshot Prediction ResultsComposite Pro le

PNL Document #�������������DNA #����ro le

PNL Document #�������������DNA #����

���������Predicted ( ) & Excluded ( ) Phenotypes

Skin Color ����Very Fair / Fair (97.6% con dence)NOT Light Olive / Dark Olive / Dark (97.6% con dence)

Eye Color ����Brown / Hazel (97.8% con dence)NOT Green / Blue / Black (97.8% con dence)

Hair Color �����Brown / Black (84.1% con dence)

Freckles ���Few / Some (75.0% con dence)

Sex: Female �Age: Unknown

(Composite shown at age 25)

Ancestry: Northern/Eastern European

NBC Nightly News and Cold Justice

Actual Photo

Page 18: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Additional Blind Predictions Additional blind predictions vs. actual photographs are available for government and law enforcement personnel

Page 19: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Cases That Have Gone Public

Fort Wayne Police Department

Miami-Dade Police Department

Calcasieu Parish Sheriff’s Office

Page 20: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

Extended Kinship Inference Developed a new method that uses machine learning to predict relatedness between two genomes

100%

100%

94%

77%

Absolute Kinship Accuracy

Accuracy Within One Degree

45%

57%

100%

100%

97.5%

100%

98%

95%

93%

99.5%

Parent

2nd-Degree

3rd-Degree

4th-Degree

5th-Degree

6th-Degree

Unrelated

100% 100% Siblings

(Grandparent, Uncle, Half-Sibling)

(First cousin, Great-grandparent)

(First cousin once-removed)

(Second cousin)

(Second cousin once-removed)

Page 21: DNA Phenotyping and Kinship Determination · Forensic Applications of DNA Phenotyping Predict a person’s ancestry and/or appearance (“phenotype”) from his or her DNA Generate

© 2015 Parabon NanoLabs, Inc. All rights reserved.

parabon-nanolabs.com/snapshot