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Forensic Biological Evidence > M5 > Flashcards

M5 Flashcards

1
Q

Methods used to ID human remains

A
  • Facial characteristics
  • Scars, marks, & other special body features
  • Dental matching
  • Fingerprint comparison
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2
Q

DNA profiles from human remains can be essential in:

A
  • Missing person investigations
  • Unidentified Remains Identification
  • Mass disaster identification
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3
Q

If a reference sample is available, follows same underlying workflow of regular DNA profile as follows:

A
  1. Generate DNA profile from unknown evidentiary sample & known reference sample, or enter into CODIS
  2. Followed by comparison of the 2
  3. Inclusion/Exclusion/Incomplete
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4
Q

Generating DNA profiles from skeletonized/decomposed human remains is

A

challenging

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5
Q

NamUS

A

National Missing and Unidentified Person System

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6
Q

What happens do DNA after death?

A
  1. DNA begins to degrade
  2. Cell death occurs
  3. Cell membranes rupture & release enzymes that degrade cellular structures
  4. Chemical reactions to modify & break the DNA strands
  5. Followed by microbes, both within & external to the body
  6. DNA degradation occurs over time
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7
Q

DNA begins to degrade

A

immediately after the cells die

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8
Q

Cell death occurs once a cell is no longer in

A

contact w/the body’s circulating oxygen supply

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9
Q

Cell membranes rupture & release enzymes that

A

degrade cellular structures

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10
Q

Chemical reaction act to

A

modify & break the DNA strands

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11
Q

DNA degradation occurs over time as hydrolytic & oxidative chemical reactions damage the molecules by

A

fragmentation & chemical modification.

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12
Q

DNA persists in bones & teeth longer than

A

soft tissues because of rigid structure (provides protection).

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13
Q

DNA binds to

A

hydroxyapatite of the hard tissues - stabilizes the DNA

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14
Q

Molecular taphonomy is the study of the

A

various intrinsic & extrinsic factors that influence the degradation of the body’s molecular structures (e.g., DNA).

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15
Q
  1. Environmental Factors
    Differential preservation in different skeletons, in different bones, within the
A

same skeleton, & even variations in DNA quality & yield across the same bone.

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16
Q

Depositional environment plays a greater role in

A

degradation than the absolute age.

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17
Q

Bone type & density

A

contributes to perservation

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18
Q

Different Environmental Factors are

A
  1. Temperatures
  2. Moisture levels
  3. Oxygen levels
  4. Microorganism Activity
  5. Soil Composition
  6. pH
  7. Bone Type
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19
Q

Temperature
Autolysis occurs at a maximum chemical activity at

A

34 degrees C to 40 degrees C
* Two-fold to three-fold increase 10 degree C

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20
Q

Temperature influences microbial activity in that

A

warmer temp increases activity, thus cooler temps will favor DNA preservation

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21
Q

Some circumstances where mild heating (during extraction) may be beneficial as it makes the

A

bone brittle, releasing out the DNA.

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22
Q
  • Moisture *
    Water molecules participate in hydrolytic reactions that
A

fragment and modify DNA

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23
Q
  • Moisture *
    The more water/humidity, the more
A

DNA damage

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24
Q
  • Moisture *
    Some circumstances where water may influence other environmental variables; for example
A

peat bog, creates low oxygen environmental and burial in salt water reduce microbial activity.

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25
Q
  • Oxygen Levels *
    Oxygen molecules participate in oxidative reaction that
A

modify DNA bases and create lesion in DNA strands.

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26
Q
  • Oxygen Levels *
    Oxidative reaction leads to degradation as well as
A

helical distortion (complicates DNA profiling)

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27
Q
  • Oxygen Levels *
    Oxygen levels influences rate and extent of
A

microbial decomposition

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28
Q
  • Oxygen Levels *
    Oxygen rich environments lead to
A

greater degradation

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29
Q
  • Microorgansim Activity*
    Microorganism activity can be
A

endogenous and exogenous

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30
Q
  • Microorganism Activity*
    Microbes do not digest the DNA directly, instead they digest the protein component of bone, making the DNA
A

more prone to damage

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31
Q
  • Microorganism Activity*
    Microbes also produce enzymes that
A

fragment DNA

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32
Q
  • Soil Composition *
    Chemical composition complicates
A

genetic analyzes

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33
Q
  • Soil Composition *
    Bones/teeth reach chemical equilibrium via mineral leaching and uptake of
A

different solutes from the soil

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34
Q
  • Soil Composition *
    Soil composition
A

degrades bone

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35
Q
  • Soil Composition *
    Causes chemical changes to be
A

hydroxyapatite

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36
Q
  • Soil Composition *
    Soil solutes contain
A

tannins and humic acids that inhibit PCR

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37
Q
  • pH *
    Decomp occurs more rapidly in
A

acidic and alkaline conditions rather than neutral

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38
Q
  • pH *
    Chemical modifications to hydroxyapatite and DNA influenced by the
A

pH of the deposition environment

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39
Q
  • pH *
    Microbial activity also influenced by the
A

pH of the environment

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40
Q
  • Bone Type *
    Bone size and construction impact
A

DNA preservation

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41
Q
  • Bone Type *
    Larger bones tend to
A

survive better

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42
Q
  • Bone Type *
    Dense cortical portions of lower limb bones and harder tissues of teeth are more consistently
A

reliable in generating DNA profiles as compared to less dense spongy bone.

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43
Q
  • Bone Type *
    Understanding skeletal elements and those most likely to produce a profile should be considered rather
A

than sampling based on convenience.

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44
Q
  • Biology of Bone *
    Rate of degradation of human remains varies greatly with environmental conditions for example
A
  • soft tissue is lost
  • Bones are more stable and remain
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45
Q
  • Biology of Bone *
    Used to identify victims in mass fatalities with techniques such as
A
  • Facial reconstruction
  • special body features (scoliosis, implants, replacements, etc.)
  • dental records
  • DNA analysis
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46
Q
  • Biology of Bone *
    Adult human skeleton contains
A

206 bones

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47
Q
  • Biology of Bone *
    Long Bone shaft is made up of
A
  • outer layer is cortical (compact) bone that is Highly dense, solid & strong
  • Middle contains marrow cavity
  • Both ends are the epiphysis, consist of cancellous (spongy) bone and is Highly Porous, takes force of compression
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48
Q
  • Biology of Bone *
    Flat bone is primarily
A

cortical or cancellous

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49
Q
  • Biology of Bone *
    Bone contains a
A

matrix of cells
that makes bone a weight bearing hard tissue

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50
Q
  • Biology of Bone *
    Inorganic cell matrix consists of
A

calcium and phosphorus
*hydroxyapatite crystals

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51
Q
  • Biology of Bone *
    Organic cell matrix consists of
A

collagens (mostly type I) and are insoluble fibrous proteins

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52
Q
  • Biology of Bone *
    Developing bones contain
A

osteoprogenitor cells

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53
Q
  • Biology of Bone *
    Osteoprogenitor cells produce
A

osteoblasts

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54
Q
  • Biology of Bone *
    Osteoblasts produce
A

new bone matrix

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55
Q
  • Biology of Bone *
    If osteoblasts are embedded in bone they are
A

Osteocytes
* most abundant cells in bones
* maintain matrix
* repair damaged bone

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56
Q
  • Biology of Bone *
    Bone that also contains osteoclasts
A

dissolve and recycle bone matrix
Large cells that contain 50+ nuclei

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57
Q
  • Bone as a Source of DNA *

Most DNA comes from

A

osteocytes
*Microgram quantities of DNA can be recovered
*Compact bone should contain enough nuclear DNA analysis

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58
Q
  • Bone as a Source of DNA *

20,000-26,000 osteocytes

A

per mm(3) of calcified bone

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59
Q
  • Bone as a Source of DNA *
    Bones from mass fatalities and burial sites are subjected to
A

decomposition, nuclear and mtDNA can become degraded

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60
Q
  • Bone as a Source of DNA *
    Bone sample must be cleaned first by
A
  1. Remove contaminating DNA
  2. Clean outer surface of bone samples prior to processing
  3. Sanding - used to reduce potential of comingled remains, adhering inhibitors, and bacterial contaminates
  4. Bone dust from sanding must be cleaned and removed
  5. Immerse in bleach solution
  6. Or exposure to UV radiation
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61
Q
  • Bone as a Source of DNA *
    A high-yield DNA extraction method
A
  1. Bone is ground/pulverized into a fine dust for DNA extraction
  2. .2g-2.5 g bone dust
  3. Incubate in extraction buffer
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62
Q
  • Bone as a Source of DNA *
    Incubate in extraction buffer consists of
A
  1. Calcified matrix is removed
  2. Decalcification procedure will dissolve calcium & soften bone tissue
  3. Proteinase will digest matrix proteins & increase yield.
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63
Q
  • Biology of Teeth *
    The Two sets of teeth form gestation are
A
  • Deciduous/Primary teeth (20 teeth)
  • Secondary/Permanent dentition (32 teeth)
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64
Q
  • Bone as a Source of DNA *
    Dental records can be used to identify a person by
A
  1. Characteristics of teeth
  2. Alignment
  3. Overall structure
  4. X-rays
  5. DNA from teeth may be used in UHRs
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65
Q
  • Bone as a Source of DNA *
    Most of a tooth consists of
A

dentin

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66
Q
  • Bone as a Source of DNA *

Crown of a tooth is covered w/

A

enamel mostly made of collagens

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67
Q
  • Bone as a Source of DNA *
    Root of a tooth is covered with
A

cementum
*Amelogenin is the major protein present

68
Q
  • Bone as a Source of DNA *
    In the inner chamber of a tooth is the
A

pulp cavity

69
Q
  • Bone as a Source of DNA *
    Dental pulp is connective tissue made of
A

cells, nerves, & blood vessels

70
Q
  • Bone as a Source of DNA *
    Root canal is narrow tunnel at base of tooth that
A

bring nerves & blood vessels from gums into pulp cavity
*Number of roots vary between different tooth types

71
Q
  • Bone as a Source of DNA *

Odontoblasts are along the

A

peripheral dental pulp. Odtontoblasts process projects into the dentinal tubule and has a large role in the formation of dentin

72
Q
  • Teeth as a Source of DNA *
    Dental pulp contains many cells that can
A

decompose if exposed to heat or humidity

73
Q
  • Teeth as a Source of DNA *
    Extract DNA by breaking open the tooth to
A

expose pulp cavity for DNA

74
Q
  • Teeth as a Source of DNA *
    Pulp tissue using endodontic access procedure:
A
  1. Trepanning the occlusal surface of a tooth using a dental bur
  2. Creating a cavity for endodontic access
  3. extracting pulp tissue using a nerve broach
75
Q
  • Lineage Markers *
    STR on sex chromosomes used to supplement the individualizing information provided by
A

autosomal STR

76
Q
  • Lineage Markers *
    Inheritance patterns of the X and Y chromosomes differ from the
A

autosomes and from each other.

77
Q
  • Lineage Markers *

Applications for Forensic Science

A
  1. Identifying testing
    *Questioned versus known
  2. Kinship testing
    * Relatedness between individuals
78
Q
  • Lineage Markers *
    Autosomes are
A

a pair one chromosome of each pair from both mother and father passed on to both male and female offspring

79
Q
  • Lineage Markers *
    X- Chromosome is
A

passed from both mother and father to female offspring, male offspring receive only one X from the mother.

80
Q
  • Lineage Markers *
    Y-Chromosome is
A

present only in MALES, is passed down in its entirety from father to son, and the alleles combine to form a profile known as a HAPLOTYPE.

81
Q
  • Lineage Markers *

Female offspring have 2

A

X chromosomes, 1 from mother and 1 from father

82
Q
  • Lineage Markers *

Male offspring have 1

A

X chromosome, 1 mother and one Y chromosome from father

83
Q
  • Lineage Markers *
    Autosomal chromosomes recombine with each
A

meiosis

84
Q
  • Lineage Markers *

Y and mtDNA does NOT recombine with each

A

meiosis. Therefore, they remain constant from generation to generation (except for mutations)

85
Q
  • Lineage Markers *

Lack of recombination in Y and mtDNA is also a disadvantage for forensic use because

A
  1. Cannot use product rule when calculating the probability of an ID
  2. Cannot separate direct relatives apart (i.e., Y DNA profile could be any male in a family).
86
Q
  • Lineage Markers *
    Identity Testing breakdown
A
  1. Autosomal STR markers are MORE informative, than either X or Y STR markers alone
  2. Y - STRs identify a LINEAGE rather than an individual
  3. X - STRs w/reduced recombination rates REDUCE individualization
  4. Both play a role in mixed stains of donors of opposite sexes
87
Q
  • Lineage Markers *
    Kinship Testing used for
A
  1. Paternity testing
  2. Criminal incest investigations
  3. Immigration cases
  4. Missing persons cases
  5. Mass disaster identifications
88
Q
  • Lineage Markers *
    Kinship Testing Examples
A
  • Motherless case; autosomal STRs not sufficient, Y-STR profile used to distinguish between a son’s 2 possible fathers
  • Fetal paternity analysis (12 weeks gestation)
89
Q
  • Y Chromosome Markers*
A
  1. Passed from father to sons
  2. Mutations can complicate matters
  3. Focus on haplotype frequencies and match probabilities
  4. Database for Y-haplotype frequencies
90
Q
  • Y Chromosome Markers*

Y-chromosomal analysis helpful in cases where;

A
  1. There is excess of DNA from a female victim & a low contribution from a male perpetrator
  2. Absence of sperm can make separation of male DNA from female DNA difficult - differential extraction
  3. Useful in determining more than one male from a mixed sample
  4. Large number of semen stains need to be separated and ID’d
  5. In missing persons investigation/Disaster Victim Identifications
91
Q
  • Y Chromosome Markers*

Useful for tracing human origins through male lineages in:

A
  1. Anthropological
  2. Historical
  3. Evolutionary history ( Y - Adam)
  4. Migration patterns
  5. Genealogy
  6. Linked w/surnames in patrilineal socities
  7. In forensic casework – used to predict a suspect’s surname
92
Q
  • Y Chromosome Markers*

Y-STR databases

A
  • NO forensic Y - STR database in U.S.
  • China was 1st to implement a large-scale forensic Y-STR database
  • Singapore, Australia, New Zealand and the Netherlands not too have a Y-STR database
93
Q
  • Y Chromosome Markers*

The 2 parts of a Y Chromosome

A
  1. Non-recombining portion - Y only
  2. PAR - recombines w/the X chromosome
94
Q
  • Y Chromosome Markers*
A
95
Q
  • Y Chromosome Markers*

The Y Chromosome

A
  • Third smallest chromosome
  • More than 1/2 of it is heterochromatin - NO GENES
  • Contains ~90 genes
  • Majority of genes = Male Specific Region (MSR)
96
Q
  • Y Chromosome Markers*

Mutations events interfere with

A
  • Paternity analysis
  • Mixture interpretation
97
Q
  • Y Chromosome Markers*

Differences at 3 or more Y-STR loci are needed before

A

exclusion dur to mutations can be determined

98
Q
  • Y Chromosome Markers*
    Y chromosome contains same sort of variation as autosomes such as
A
  • STRs
  • SNPs
  • Alu Repeats
  • Minisatelites
  • STRs give the most information, but have a HIGHER mutation rate
99
Q
  • Y Chromosome Markers*
    Y-STR Markers
A
  • 1997 a core set of Y-STRs were selected
  • Collectively termed “MINIMAL HAPLOTYPE” and are required for population database inclusion and searching.
100
Q
  • Y Chromosome Markers*

Y-STR Markers Core set

A

DYS19
*DYS3891
*DYS389I 1/II
*DYS390
*DYS391
*DYS392
*DYS393
*DYS385a/b
*DYS438
*DYS439

101
Q
  • Y Chromosome Markers *
    Commercial Y-STR multiplexes report ability to detect male DNA in male : female mixture rations up to
A

1:24,000
Requires as little as 62.5 pg of MALE DNA

102
Q
  • Y Chromosome Markers*
    Benefit Combining Y & Autosomal
A
  1. Limited number of autosomal STR loci
  2. Added power to distinguish the DNA sample
  3. Calculate most conservative minimum frequency for Y-STR profile
  4. Then multiple it by the frequency of the autosomal STRs you have
  5. Will calculate overall DNA profile
103
Q
  • Y Chromosome Markers*
    Results in Y-STR Profile
A
  1. Exclusion - did not originate from sample
  2. Inconclusive - insufficient distinguishing power
  3. Failure to Exclude - Sample MAY be from same source or ANY MALE relative source
104
Q
  • X Chromosome Markers*
A
  1. Useful in any parent-child relationship involving at least 1 female
  2. X-STRs useful in extracting the female portion of male : female mixtures in the presence of large excesses of male DNA.
105
Q
  • X Chromosome Markers*
    Male X-STR profile will NOT completely mask the female profile, UNLESS female profile coincidentally
A

homozygous for all of the male matching alleles (highly unlikely).

106
Q
  • X Chromosome Markers*

Genetic inconsistencies can complicate

A

STR interpretation

107
Q
  • X Chromosome Markers*
    Useful in cases where the true father of a daughter is related to
A

the alleged father.

108
Q
  • X Chromosome Markers*

Criminal incest investigations and paternity cases

A

involving blood relatives.

109
Q
  • X Chromosome Markers*
    X-STRs can differentiate pedigrees that are otherwise indistinguishable by
A

unlinked autosomal STRs

110
Q
  • X Chromosome Markers*
    Contains ~1,500 genes with some dealing with
A

sexual development

111
Q
  • X Chromosome Markers*
    Currently no efforts to standardize X-STRs used
A

in forensic investigations

112
Q
  • X Chromosome Markers*
    There are at least
A

39 X-STR markers

113
Q
  • X Chromosome Markers*
    No centralized repositories for the collection, storage, and utilization of
A

X-STR allele or haplotype frequencies.

114
Q
  • Mitochondrial DNA (mtDNA)*
    What is found in mitochondria
A

Bacteria like
* Circular
* No recombination
* Short and no-nonsense

115
Q
  • Mitochondrial DNA (mtDNA)*

Mitochondrial DNA is passed on from a

A

MOTHER to ALL children

116
Q
  • Mitochondrial DNA (mtDNA)*
    Due to high copy number (more copies), it is useful in analyses of low target number DNA for example
A

unidentified skeletonized remains, hair shafts w/out roots, or old degraded samples

117
Q
  • Mitochondrial DNA (mtDNA)*

In mtDNA there are ~16,569

A

nucleotides
* 37 genes (energy producer)
* Non-coding “control region_
– D-Loop Sufficient variation for identify testing

118
Q
  • Mitochondrial DNA (mtDNA)*
    A person’s mtDNA sequence is called a
A

mitotype

119
Q
  • Mitochondrial DNA (mtDNA)*
    Polymorphic regions (HV1 and HV2) in control region
A

called D-Loop

120
Q
  • Mitochondrial DNA (mtDNA)*

Hypervariable regions

A

HV1 (16,024; 342 bp)
HV2 (73-340; 248 bp)

121
Q
  • Mitochondrial DNA (mtDNA)*
    Revised Cambridge Reference Sample was the
A
  • First human mtDNA genome sequence
  • Later revised to correct mistakes: rCRS
  • Used as reference for mitotype nomenclature
122
Q
  • Mitochondrial DNA (mtDNA)*
    Advantages in Forensic Investigations:
A
  • Both males and females can be tested
  • Ample material to generate profile
  • Can test ancient and degraded samples
123
Q
  • Mitochondrial DNA (mtDNA)*
    Disadvantages in Forensic investigations:
A
  • Low power of discrimination - only maternally inherited
  • Less polymorphic than nuclear DNA
  • More subject to contamination
  • Hard to correlate w/surname
  • No female children - line dies
  • Labor intensive
  • Costly
124
Q
  • Mitochondrial DNA (mtDNA)*

mtDNA Interpretation

A
  • Cannot Exclude
    – Questioned sample has the same sequence as known/reference samples.
  • Exclusion
    – 2 or more nucleotides difference between questioned & know/reference sample
  • Inconclusive
    – Questioned and known/reference sample differ by one nucleotide
125
Q
  • What is Familial DNA Searching (FDS)? *
    FDS uses
A

STR data, NOT SNP data

126
Q
  • What is Familial DNA Searching (FDS)? *
    Deliberate search of a DNA database to potentially identify close
A

biological relatives

127
Q
  • What is Familial DNA Searching (FDS)? *
    Familial searching is NOT
A

Forensic/investigative Genetic genealogy

128
Q
  • What is Familial DNA Searching (FDS)? *
    Typically used in NO suspect cases,
A

cold cases, violent crimes to develop investigative leads.

129
Q
  • What is Familial DNA Searching (FDS)? *
    2 parts to the process are
A
  1. the software ranks candidate offender relatives in order of LIKELIHOOD that they are closely related to the person who left the DNA.
  2. all of the offender candidates’ samples are subjected to additional DNA typing existing Y - chromosome testing etc.
130
Q
  • What is Familial DNA Searching (FDS)? *
    Fundamentals of Paternity Testing
A

Parent-offspring will share 1 allele at every LOCUS

131
Q
  • What is Familial DNA Searching (FDS)? *
    Kinship Analysis: Full Siblings
A

Full siblings may share 2, 1, or 0 alleles at a LOCUS.
* For more distant familial relationships, allele sharing decreases then uncertainty increases.

132
Q
  • What is Familial DNA Searching (FDS)? *
    Searching there are 3 different Stringency Levels
A
  1. High Stringency - requires ALL alleles to match
  2. Moderate and Low Stringency - allows for partially degraded & mixed DNA samples
133
Q
  • What is Familial DNA Searching (FDS)? *
    Results in “PARTIAL MATCHES”, which show a sufficient degree of genetic similarity to indicate a
A

potential familial relationship

134
Q
  • What is Familial DNA Searching (FDS)? *

FBI definition of Partial Matching (PM)

A

is the spontaneous product of a routine database search where a candidate offender profile is NOT identical to the forensic profile but because of a similarity in the NUMBER of ALLELES shared between the forensic profile, the offender may be a close biological relative of the source of the forensic profile.
** A moderate stringency search of a DNA database using the routine parameters w/in CODIS

135
Q
  • What is Familial DNA Searching (FDS)? *

FBI defines FDS as

A

an intentional or deliberate search of the database conducted after a routine search for the purpose of potentially identifying close biological relatives of the unknown forensic sample associated w/the crime scene profile.

136
Q
  • What is Familial DNA Searching (FDS)? *

CODIS software is NOT intentionally designed for

A

FDS
* FDS is NOT allowed at the national level, only at state and local levels.
* Allows a ranked list of all the potential familial relations

137
Q
  • What is Familial DNA Searching (FDS)? *
    Restrictions on what cases are ELIGIBLE for FDS:
A
  1. Crimes posing significant public safety threat
  2. Many states also regulate the point in a case when FDS can be pursued
  3. Most mandate that all other investigative leads must be exhausted.
  4. Must be from a SINGLE-SOURCE sample
  5. Minimum number of core CODIS loci that must be present
138
Q
  • What is Familial DNA Searching (FDS)? *
    Kinship
A
  1. The more similar 2 profiles are - the higher the probability of kinship
  2. Parent - Child
  3. Full Siblings
  4. Unrelated
139
Q
  • What is Familial DNA Searching (FDS)? *
    Familial DNA database searches are best for 2 lines of inquiry
A
  1. The identity of an individual who could be a sibling of the offender
  2. The identity of an individual who could be the offender’s parent or child
140
Q
  • What is Familial DNA Searching (FDS)? *
    It is important to recognize that a RELATIVE MUST ALREADY BE IN THE DATABASE in order for the search to
A

identify them as a potential relative of the forensic profile.

141
Q
  • What is Familial DNA Searching (FDS)? *
    Even if a relative is in the database it is possible the RELATIVE MAY NOT BE INCLUDED in the
A

ranked list produced by the familial search.

142
Q
  • Kinship Analysis *
    Identity by State (IBS) is to
A

count the number of shared alleles and is a statistical technique that determines genetic relatedness or similarity based on the number of matching markers between 2 genetic profiles

143
Q
  • Kinship Analysis *
    Likelihood ration (LR) of Kinship Index (KI) compares the probability of 2 profiles being from biologically related sources to the
A

probability of them being from unrelated sources.

144
Q
  • Kinship Analysis *

LR/KI does NOT

A

produce rankings

145
Q
  • Kinship Analysis *

LR/KI requires population characteristics and takes into account that STR alleles vary with different

A

frequencies, thus the population used in this analysis may impact the accuracy.

146
Q
  • Kinship Analysis *

Scientific Working Group on DNA Analysis Methods (SWGDAM) provided CODIS Unit w/ the following 3 recommendations:

A
  1. The us of kinship LRs is the preferred method for familial searching
  2. Ranked lists should be reviewed
  3. Routine familial searching at the NATIONAL level is not recommended at this time because it is difficult to establish a threshold ranking for review of a ranked list
147
Q
  • Implementation *
    US Implementation
A
  1. FBI does NOT currently conduct familial searches
  2. The only limitation this has for states is that their familial searches can only be conducted w/in their state-level and local-level databases.
148
Q
  • The Need for Speed *
    Rapid DNA technology could be an effective tool to
A

eliminate DNA backlog w/in accredited DNA laboratories & have potential for application in FIELD BASED environments

149
Q
  • The Need for Speed *

FBI define Rapid DNA as

A

a term used to describe the fully automated process of developing a DNA profile from a reference sample buccal swab w/o human intervention

150
Q
  • The Need for Speed *

The development of Rapid DNA technologies began with the aims:

A
  1. To establish a tool which could produce a DNA profile in much-reduced time-period
  2. To take this instrumentation out of the laboratory and into the field
  3. To develop a technology that would be housed w/in 1 unit and could be operated by non-technical users.
151
Q
  • The Need for Speed *

ANDE Corporation Accelerated Nuclear DNA Equipment

A
  • Dr. Richard Selden, Founding Director, 2004
  • 1st Rapid DNA platform
  • 1st to receive NDIS approval
152
Q
  • The Need for Speed *
    Applied Biosystems
A
  • RapidHIT Systems
  • 2011 - produced a Rapid DNA system for the Army’s Biometrics Identity Management Agency
  • To date has uploaded >1000 STR profiles to NDIS
153
Q
  • The Need for Speed *

Rapid DNA Act 2017

A
  • August 18, 2017 signed into U.S. Federal Law
  • Amended to original DNA Identification Act of 1994
  • Allows DNA profiling of arrestees in booking station environment
154
Q
  • The Need for Speed *

The aim of the Rapid DNA Act was to “establish a system for integration of Rapid DNA instruments for use by law enforcement to reduce

A

violent crime and reduce the current DNA analysis backlog

155
Q
  • The Need for Speed *

2 important features of the Rapid DNA Act are

A
  1. The generation and analysis must be fully automated
  2. The FBI must approve the Rapid DNA systems for use, and also establish the standards and procedures for use
156
Q
  • Technology *
    ANDE Platforms - FAIRS
A
  • Databases can be created w/in the FAIRS software
  • To perform Kinship Testing
  • Useful for border control, emigration, & human trafficking
157
Q
  • Technology *
    ANDE Platforms - RapidHit Systems
A
  • 2013 first produced
  • PowerPlex 16HS Chemistry
158
Q
  • Rapid DNA Applications *
    Why is it beneficial to use in Booking Stations?
A
  1. Decentralize environment
  2. Expedite arrestee identification
  3. Link the arrestee to prior crimes
  4. Other levels of info collected/searched
    • Fingerprints, criminal history
  5. Collect buccal swab
  6. Generate CODIS searchable profile
    • Positively impact the current backlog of reference sample processing
  7. Search for linkages
  8. Currently 5 pilot site utilizing Rapid DNA in booking station environments
159
Q
  • Rapid DNA Applications *
    3 Prerequisites for Implementing Rapid DNA at booking stations
A
  1. The state must have implemented an arrestee DNA collection law that authorizes DNA analysis at the time of arrest. *Federal booking agencies already meet the prerequisite *
  2. They must have ELECTRONIC FINGERPRINT (Live Scan) INTEGRATION during the booking process for obtaining State Identification numbers (SID) from the State Identification Bureau in near real-time.
  3. The booking agency must have network connectivity w/the State Identification Bureau (SIB)/Criminal Justice Information Services (CJIS) Systems Agency (CSA).
160
Q
  • Rapid DNA Applications *
    Accredited Crime Lab Uses
A
  1. Known reference buccal samples submitted to the laboratory
  2. Blood, other forensically relevant body fluids, and touch DNA sampled from evidence items examined in the laboratory
  3. Sexual Assault Kits (SAKs) that are currently backlogged and remain untested
161
Q
  • Rapid DNA Applications *
    Forensic samples not compliant with FBI Quality Assurance Standards require
A

human quantitation.
* If does not meet quality assurance do not have approval for upload and searching in CODIS
* CAN validate individual Rapid DNA w/in local and state databases
* KENTUCKY first to use on sexual assault samples

162
Q
  • Rapid DNA Applications *
    Field Use
A
  1. Mass disaster/mass casualty sites
  2. Battlefields
  3. Border control stations
  4. Small footprint
  5. No maintenance or optical calibration following transport
  6. Operate using a standard power supply
163
Q
  • Rapid DNA Applications *
    Border Control, Immigration, & Human Trafficking Investigations
A
  • May 2019 - DHS - Pilot program to DNA test at U.S. Border from Mexico
    1. Suspected fraudulent parentage or kinship claims
    2. Vulnerable children could be removed from potentially dangerous situations
    3. Obvious limitations
    – parentage through adoption
    – parent may not know they are not the biological parent
    4. Creation of global databases of human trafficking victims
164
Q
  • Rapid DNA Applications *
    Disaster Victim Identification (DVI)
A
  1. Severely damaged, dismembered, fragmented, commingled, varying states of decomposition, even skeletonized
  2. Disaster Mortuary Operational Response Teams (DMORTs)
  3. Instruments can be shipped in an expeditious and efficient manner
    Ex. 2018 Camp Fire, Conception boat fire, Kobe Bryant helicopter crash
165
Q
A

Forensic Biological Evidence (3 decks)

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