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Snowball the Cat and Other Tales of Forensic Science Donna C. Sullivan, PhD Division of Infectious Diseases University of Mississippi Medical Center.

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Presentation on theme: "Snowball the Cat and Other Tales of Forensic Science Donna C. Sullivan, PhD Division of Infectious Diseases University of Mississippi Medical Center."— Presentation transcript:

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2 Snowball the Cat and Other Tales of Forensic Science Donna C. Sullivan, PhD Division of Infectious Diseases University of Mississippi Medical Center

3 Polymorphism A DNA polymorphism is a sequence difference compared to a reference standard that is present in at least 1–2% of a population. A DNA polymorphism is a sequence difference compared to a reference standard that is present in at least 1–2% of a population. Polymorphisms can be single bases or thousands of bases. Polymorphisms can be single bases or thousands of bases. Polymorphisms may or may not have phenotypic effects. Polymorphisms may or may not have phenotypic effects.

4 Types of Polymorphic DNA Sequences RFLP: restriction fragment length polymorphisms RFLP: restriction fragment length polymorphisms VNTR: variable number tandem repeats (8 to >50 base pairs) VNTR: variable number tandem repeats (8 to >50 base pairs) STR: short tandem repeats (1–8 base pairs) STR: short tandem repeats (1–8 base pairs) SNP: single-nucleotide polymorphisms SNP: single-nucleotide polymorphisms

5 DNA DIFFERS PERSON TO PERSON All individuals genetically unique (except identical twins) All individuals genetically unique (except identical twins) Differences in DNA sequence detected by Differences in DNA sequence detected by RFLP using large quantities intact DNA RFLP using large quantities intact DNA PCR in conjunction with various methods PCR in conjunction with various methods Single nucleotide polymorphisms (SNPs) Single nucleotide polymorphisms (SNPs)

6 DNA Profiles from12 Unrelated Individuals At ONE Polymorphic Locus

7 RFLP ANALYSIS: Detect Alleles by Southern Blot Hybridization Analysis of VNTR locus by Southern blot most commonly results in two-band pattern, comprised of a band inherited from each parent Analysis of VNTR locus by Southern blot most commonly results in two-band pattern, comprised of a band inherited from each parent Single band patterns possible with 2 alleles of same size Single band patterns possible with 2 alleles of same size For 3 different alleles, six different genotypes possible For 3 different alleles, six different genotypes possible

8 RFLP Analysis: Detect Alleles by Southern Hybridization

9 Restriction Fragment Length Polymorphisms RFLP genotypes are inherited. RFLP genotypes are inherited. For each locus, one allele is inherited from each parent. For each locus, one allele is inherited from each parent. Southern blot band patterns

10 CALCULATION OF POSSIBLE GENOTYPES For N different alleles, total possible genotypes: For N different alleles, total possible genotypes: (n X (n+1)) 2 For 3 alleles, 6 genotypes For 3 alleles, 6 genotypes For 4 alleles, 10 genotypes For 4 alleles, 10 genotypes For 5 alleles, 15 genotypes For 5 alleles, 15 genotypes

11 VNTR: Variable Number Tandem Repeats Short sequence of DNA repeated in head- to-tail fashion Short sequence of DNA repeated in head- to-tail fashion Occur at specific chromosomal locations Occur at specific chromosomal locations Interspersed throughout human genome Interspersed throughout human genome Number of repeated units vary between individuals Number of repeated units vary between individuals

12 Multiple Alleles at VNTR loci

13 Distinguish Individuals by Combination of Alleles at VNTR Loci

14 Short Tandem Repeat Polymorphisms (STR) STR are repeats of nucleotide sequences. STR are repeats of nucleotide sequences. AAAAAA… - mononucleotide AAAAAA… - mononucleotide ATATAT… - dinucleotide ATATAT… - dinucleotide TAGTAGTAG… - trinucleotide TAGTAGTAG… - trinucleotide TAGTTAGTTAGT… - tetranucleotide TAGTTAGTTAGT… - tetranucleotide TAGGCTAGGCTAGGC… - penta nucleotide TAGGCTAGGCTAGGC… - penta nucleotide Different alleles contain different numbers of repeats. Different alleles contain different numbers of repeats. TTCTTCTTCTTC - four repeat allele TTCTTCTTCTTC - four repeat allele TTCTTCTTCTTCTTC - five repeat allele TTCTTCTTCTTCTTC - five repeat allele

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16 Short Tandem Repeat Polymorphisms Allelic ladders are standards representing all alleles observed in a population. Allelic ladders are standards representing all alleles observed in a population. (Allelic ladder) 11 repeats 5 repeats Genotype: 7,9 Genotype: 6,8

17 M S1 S2 V E M Locus 1 Locus 2 Locus 3 Evidence Testing by STR-PCR Which suspect—S1 or S2—was at the crime scene? Which suspect—S1 or S2—was at the crime scene? (V = victim, E = crime scene evidence, M = molecular weight standard)

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20 Short Tandem Repeat Polymorphisms by Multiplex PCR FGA TPOX D8S1179 vWA PentaE D18S51 D2S11 THO1 D3S1358

21 STR-PCR STR genotypes are inherited. STR genotypes are inherited. One allele is inherited from each parent. One allele is inherited from each parent. Child’s alleles Mother’s alleles Father’s alleles

22 Single Nucleotide Polymorphisms (SNP) Single-nucleotide differences between DNA sequences. Single-nucleotide differences between DNA sequences. One SNP occurs approximately every 1,250 base pairs in human DNA. One SNP occurs approximately every 1,250 base pairs in human DNA. SNPs are detected by sequencing, melt curve analysis, or other methods. SNPs are detected by sequencing, melt curve analysis, or other methods. 99% have no biological effect; 60,000 are within genes. 99% have no biological effect; 60,000 are within genes.

23 Top Ten Ways to Know that You are a Forensic DNA Scientist 10.You have your children’s DNA profiles framed on your desk instead of their pictures. 9.When your children hurt themselves, you are more interested in collecting their blood to generate a DNA profile than getting them cleaned up… 8.Your pockets are full of napkins with DNA sequences written on them. 7.You want to name your first four kids: Adenine, Thymine, Guanine, and Cytosine. 6.You wonder how jello would work as a separation medium…and have tried it when no one else was around…but were too afraid to publish the results.

24 Top Ten Ways to Know that You are a Forensic DNA Scientist 5.You want to start a paternity testing business for all those who appear on the Jerry Springer show. 4.You know that DNA stands for more than the National Dyslexics Association. 3.You want to do a study on the genetics of inbreeding…and have selected the Reservoir deer population for a case study.

25 Top Ten Ways to Know that You are a Forensic DNA Scientist 2.You know that “scientists” on the popular TV show CSI: Crime Scene Investigation cannot possibly get their DNA results within the timeframe of a single commercial break. 1.Your license plate reads: OJ DID IT!

26 LOCARD TRANSFER THEORY “When two objects come in contact, traces from one will be transferred from one to another, and in both directions.”

27 FORENSCI SCIENCE CONCEPTS Identification Identification Classification: characteristics shared by items (Firearms, Shoes) Classification: characteristics shared by items (Firearms, Shoes) Groups (Same type of gun, same size shoe) Groups (Same type of gun, same size shoe) Individualization Individualization Created by random acts (rifling on bullets) Created by random acts (rifling on bullets) Fingerprints (influenced by environmental, developmental factors) Fingerprints (influenced by environmental, developmental factors) Traits that are so rare, alone or in combination, that they can not be duplicated by chance Traits that are so rare, alone or in combination, that they can not be duplicated by chance

28 DNA Identification Applications Sexual assault Sexual assault Homicide and other violent crimes Homicide and other violent crimes Exculpate wrongly accused suspects Exculpate wrongly accused suspects Identify serial crimes Identify serial crimes Identify human remains Identify human remains Sex offender tracking Sex offender tracking Parentage testing Parentage testing

29 In The Beginning Alec Jeffreys, geneticist at University of Leicester, UK Alec Jeffreys, geneticist at University of Leicester, UK Coined the term “DNA fingerprinting” Coined the term “DNA fingerprinting” RFLP analysis RFLP analysis Demonstrated that forensic samples, even dried stains several years old, contained sufficient DNA to yield conclusive results Demonstrated that forensic samples, even dried stains several years old, contained sufficient DNA to yield conclusive results

30 Finding A Pitchfork In The Haystack: Midlands Rapes Two British schoolgirls raped and murdered Two British schoolgirls raped and murdered Kitchen porter at an insane asylum confessed to one of the murders Kitchen porter at an insane asylum confessed to one of the murders Were both crimes committed by the same man? Were both crimes committed by the same man? Did the kitchen porter do it? Did the kitchen porter do it?

31 Finding A Pitchfork In The Haystack: Midlands Rapes Semen samples from rape/murder scenes: Semen samples from rape/murder scenes: Both crimes committed by same man Both crimes committed by same man Blood sample from kitchen porter: Blood sample from kitchen porter: Did not match crime scene evidence Did not match crime scene evidence Police felt that the murderer was a local Police felt that the murderer was a local Tested DNA from every man between the age of (4,582 men) in the local area Tested DNA from every man between the age of (4,582 men) in the local area No matches found No matches found

32 Finding A Pitchfork In The Haystack: Midlands Rapes Local baker over-heard some colleagues in a pub Local baker over-heard some colleagues in a pub Colin Pitchfork, another baker, had convinced another employee to give blood in his place Colin Pitchfork, another baker, had convinced another employee to give blood in his place Police arrested Pitchfork (he immediately confessed) Police arrested Pitchfork (he immediately confessed) Pitchfork’s DNA was perfect match to crime scene evidence (4,583 rd man tested) Pitchfork’s DNA was perfect match to crime scene evidence (4,583 rd man tested)

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35 Evaluation Of Evidence Establish type of biological material present in sample Establish type of biological material present in sample Is it blood? Catsup? Is it blood? Catsup? Is it human blood? Is it human blood? “State of the DNA” “State of the DNA” How much degradation of the DNA is there? How much degradation of the DNA is there? How much total DNA is present? How much total DNA is present? How much DNA is human? How much DNA is human?

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37 Forensic Blood Typing ABO groups ABO groups Phosphoglucomutase (PGM) Phosphoglucomutase (PGM) Erythrocyte acid phosphatase (EAP) Erythrocyte acid phosphatase (EAP) Haptoglobin Haptoglobin Adenylate kinase (AK) Adenylate kinase (AK)

38 Semen Can Be Identified With Several Laboratory Tests Acid Phosphatase - a presumptive test Acid Phosphatase - a presumptive test Anti P30 - a quantitative and qualitative test that identifies the presence of the protein P30 found only in human semen Anti P30 - a quantitative and qualitative test that identifies the presence of the protein P30 found only in human semen Spermatozoa search - a microscopic analysis visually observing the presence of sperm cells Spermatozoa search - a microscopic analysis visually observing the presence of sperm cells

39 HLA DQ  /HLA DQA1 System HLA: human lymphocyte antigens HLA: human lymphocyte antigens Determine whether patient has antibodies against a potential donor’s HLA antigens Determine whether patient has antibodies against a potential donor’s HLA antigens HLA DQ  is historic name for this region HLA DQ  is historic name for this region A 242 bp region with variation detected with specific probes for subregions A 242 bp region with variation detected with specific probes for subregions

40 HLA DQ  /HLA DQA1 System Original test could detect 6 common DQ  alleles, 21 possible genotypes Original test could detect 6 common DQ  alleles, 21 possible genotypes Subsequent analysis, renaming by geneticists resulted in DQA1 test, increased number of subtypes detected (up to 28 detectable types) Subsequent analysis, renaming by geneticists resulted in DQA1 test, increased number of subtypes detected (up to 28 detectable types) Cheap, fast color reactions Cheap, fast color reactions

41 Mixed Vs Contaminated Samples MIXED SAMPLES MIXED SAMPLES Contain DNA from more than one individual Contain DNA from more than one individual Mixing occurs before or during commission of a crime Mixing occurs before or during commission of a crime CONTAMINATED SAMPLES CONTAMINATED SAMPLES Materials deposited during collection, preservation, handling or analysis Materials deposited during collection, preservation, handling or analysis

42 HOW MUCH SAMPLE DO YOU NEED?

43 Gender Identification Amelogenin gene for tooth pulp found on sex chromosomes ( one on X, one on Y) Amelogenin gene for tooth pulp found on sex chromosomes ( one on X, one on Y) Different size PCR products from X and Y copies of the gene: Different size PCR products from X and Y copies of the gene: X Chromosome 106 bp PCR product X Chromosome 106 bp PCR product Y Chromosome 112 bp PCR product Y Chromosome 112 bp PCR product “Right side primers” “Right side primers” Located to right of amelogenin gene, included amelogenin gene Located to right of amelogenin gene, included amelogenin gene X chromosome 549 bp (set 1), 977 bp (set 2) X chromosome 549 bp (set 1), 977 bp (set 2) Y Chromosome 360 bp (set1), 788 bp (set2) Y Chromosome 360 bp (set1), 788 bp (set2)

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45 DNA/CSI Quiz True or false: DNA results take 8 minutes DNA results take 8 minutes DNA results can tell investigators what a suspect looks like DNA results can tell investigators what a suspect looks like All CSIs are good looking and solve crimes wearing Armani All CSIs are good looking and solve crimes wearing Armani CSI investigators drive Hummers, especially in Florida CSI investigators drive Hummers, especially in Florida Compliments of Linda Ledray Compliments of Linda Ledray

46 The Combined DNA Index System (CoDIS) A database of DNA profiles from violent felons and crime scene samples A database of DNA profiles from violent felons and crime scene samples Laws concerning who is eligible for the database vary from state to state Laws concerning who is eligible for the database vary from state to state Database currently contains about 2,038,470 felons and 93,956 crime scene profiles (19,00 hits so far) Database currently contains about 2,038,470 felons and 93,956 crime scene profiles (19,00 hits so far)

47 The Mystical Power of CoDIS Extremely powerful investigative tool, linking crimes, and pulling suspects out of thin air! Extremely powerful investigative tool, linking crimes, and pulling suspects out of thin air! Can prevent, as well as solve crimes! Can prevent, as well as solve crimes! NOT!!!! NOT!!!!

48 Different Systems, Different Markers

49 CODIS Profile

50 STR Data (cont’d)

51 STR data (cont’d) “The DNA profile obtained from Item 25(S) matches the DNA profile of the suspect. The combination of genetic marker types exhibited by Item 25(S) and the suspect occurs in approximately one in one hundred quadrillion (10 17 ) individuals…”

52 POPULATION DATABASES: STR Analysis Probability calculations based on knowing allele frequencies for a representative population Probability calculations based on knowing allele frequencies for a representative population For a heterozygous individual, if the two alleles have frequencies of p and q in a population, probability (P) of having both alleles at a single locus For a heterozygous individual, if the two alleles have frequencies of p and q in a population, probability (P) of having both alleles at a single locusP=2pq

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54 Mitochondrial DNA (mtDNA)

55 Mitochondrial DNA Polymorphisms Mitochondria are maternally inherited. Mitochondria are maternally inherited. There are an average of 8.5 base differences in the mitochondrial HV sequences of unrelated individuals. There are an average of 8.5 base differences in the mitochondrial HV sequences of unrelated individuals. All maternal relatives will have the same mitochondrial sequences. All maternal relatives will have the same mitochondrial sequences. Mitochondrial typing can be used for legal exclusion of individuals or confirmation of maternal lineage. Mitochondrial typing can be used for legal exclusion of individuals or confirmation of maternal lineage.

56 Y-STRs Problem: ~99% of violent crimes are committed by men ~99% of violent crimes are committed by men DNA Mixtures of male suspect and female victim can pose an analytical challenge, especially when the female contribution is much greater than the male = preferential amplification DNA Mixtures of male suspect and female victim can pose an analytical challenge, especially when the female contribution is much greater than the male = preferential amplification

57 Y-STRs Solution: Test for markers found only on the Y- chromosome. Only male DNA is amplified! Test for markers found only on the Y- chromosome. Only male DNA is amplified!

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59 Y-STRs Lower power of discrimination - paternal relatives all share the same Y-STR haplotype (“Wicked Uncle Ernie” Defense) Lower power of discrimination - paternal relatives all share the same Y-STR haplotype (“Wicked Uncle Ernie” Defense) 10% of Central Asian males share the same Y-STR haplotype, thought to belong to Genghis Khan 10% of Central Asian males share the same Y-STR haplotype, thought to belong to Genghis Khan

60 Serial Killer Case Sept. 15, 1990, Prague: woman found strangled, apparently sexually assaulted Sept. 15, 1990, Prague: woman found strangled, apparently sexually assaulted Jan April 1992, Austria: bodies of 7 prostitutes discovered in wooded areas in different parts of Austria Jan April 1992, Austria: bodies of 7 prostitutes discovered in wooded areas in different parts of Austria Missing between days Missing between days Same cause of death, pattern of disposal and positional posing of bodies Same cause of death, pattern of disposal and positional posing of bodies No relevant biological evidence suitable for DNA analysis No relevant biological evidence suitable for DNA analysis

61 Serial Killer Case May, 1991, Austria: potential suspect identified by retired homicide detective May, 1991, Austria: potential suspect identified by retired homicide detective Similar to 1975 case in Germany in which 18 year old girl strangled with her own brassier Similar to 1975 case in Germany in which 18 year old girl strangled with her own brassier June-July, 1991, Los Angeles: bodies of 3 prostitutes discovered June-July, 1991, Los Angeles: bodies of 3 prostitutes discovered Strangled with their own brassieres Strangled with their own brassieres Linked all three based on characteristics of cuts to bras, knots used Linked all three based on characteristics of cuts to bras, knots used

62 Serial Killer Case Suspect arrested in German case in 1975, convicted, sentenced to life in prison (which means he got out on parole in May, 1990) Suspect arrested in German case in 1975, convicted, sentenced to life in prison (which means he got out on parole in May, 1990) While in prison, man became an author and journalist While in prison, man became an author and journalist Police able to tract suspect’s movements, match with times of murders in Prague, Austria, Los Angeles Police able to tract suspect’s movements, match with times of murders in Prague, Austria, Los Angeles

63 Serial Killer Case Circumstantial evidence: Circumstantial evidence: Travel activity Travel activity No alibi No alibi Similarity to Prague murder for which he had been convicted Similarity to Prague murder for which he had been convicted Physical evidence (June, 1992) Physical evidence (June, 1992) Several head hairs found on the seat of suspect’s BMW (driven in Sept. 1990, sold, scraped--except the seats, which remained in a garage for 18 months) Several head hairs found on the seat of suspect’s BMW (driven in Sept. 1990, sold, scraped--except the seats, which remained in a garage for 18 months)

64 Hair Found On Suspect’s Car Seat

65 Serial Killer Case Isolated 9 nanograms human DNA from hair Isolated 9 nanograms human DNA from hair June, 1993: 2 ng for HLA-DQA typing (1:13 match to Prague victim) June, 1993: 2 ng for HLA-DQA typing (1:13 match to Prague victim) Amplitype PM PCR typing: confirmation of match and frequency of 1 in 2,300 Amplitype PM PCR typing: confirmation of match and frequency of 1 in 2,300 April, 1994: 2 ng for STR analysis (3 loci) April, 1994: 2 ng for STR analysis (3 loci) June, 1994: 1 ng for Amelogenin locus June, 1994: 1 ng for Amelogenin locus

66 Serial Killer Case VICTIMEVIDENCE

67 Serial Killer Case Discrimination to 1 in 2.1 million women Discrimination to 1 in 2.1 million women Confirmed identity of individual contributing the hair sample recovered from car seat by reverse paternity Confirmed identity of individual contributing the hair sample recovered from car seat by reverse paternity Suspect convicted in Austrian court system, sentenced to life in prison for murder of nine women, including the Prague murder Suspect convicted in Austrian court system, sentenced to life in prison for murder of nine women, including the Prague murder Suspect committed suicide by hanging himself in jail Suspect committed suicide by hanging himself in jail

68 Child Molestation Case

69 Example of Actual DNA Evidence Presented to a Jury

70 DNA Profile Warrant

71 How Do You Identify Someone Who Has Never Been Genotyped? Need genetic information from their family members Need genetic information from their family members Parents: Half of the missing persons alleles must be present in one parent, half in the other parent Parents: Half of the missing persons alleles must be present in one parent, half in the other parent Spouses and children: Half of the genes from child will be from spouse, half from missing parent Spouses and children: Half of the genes from child will be from spouse, half from missing parent

72 MISSING FATHER: What is his genotype? 1. Child (A, C) 2. Child (C, D) 3. Mother (B, C) 4. Child (B, D) 5. Child (A, B) Missing Father must be A and D genotype.

73 MISSING MOTHER: What is her genotype? 1. Father (B and C) 2. Child (A, B) 3. Child (A, C) 4. Child (B, D) 5. Child (C, D) Missing Mother must be phenotype A and D

74 Using Personal Effects to Identify Remains

75 Using Family Members to Identify Remains

76 PRENATAL DIAGNOSIS OF RAPE VICTIMS Study looked at 10 victims of sexual assault who became pregnant Study looked at 10 victims of sexual assault who became pregnant Prior to testing they were interviewed about continuing the pregnancy Prior to testing they were interviewed about continuing the pregnancy All women had a consensual partner who was also potential father of unborn child All women had a consensual partner who was also potential father of unborn child

77 PRENATAL DIAGNOSIS OF RAPE VICTIMS Inclusion: match between husband and fetus Inclusion: match between husband and fetus Exclusion: no match between husband and fetus Exclusion: no match between husband and fetus (Rule out, rule in. In criminal cases, may obtain inconclusive result) (Rule out, rule in. In criminal cases, may obtain inconclusive result)

78 PRENATAL DIAGNOSIS OF RAPE VICTIMS

79 CASE RESULTS: In Utero Paternity Testing Terminate0.00TerminationNoMarried10 Continue99.19TerminationNoMarried9 Continue0.00AdoptionNoSingle8 Continue99.99AdoptionNoMarried7 Terminate0.00TerminationNoMarried6 Continue99.99AdoptionNoSingle5 Continue99.99AdoptionYesEngaged4 Terminate0.00TerminationNoMarried3 Continue99.95TerminationNoMarried2 Continue99.99TerminationNoMarried1 Pregnancy Decision Partner Paternity Probability Pre Test Attitude Police Report Marital status Case Hammond et al, JAMA 273: 1774 (1995)

80 Snowball the Cat: Prince Edward Island, Canada In 1994, Shirley Duguay, a 32-year-old mother of five, disappeared. Her body was found in a shallow grave a few months later. In 1994, Shirley Duguay, a 32-year-old mother of five, disappeared. Her body was found in a shallow grave a few months later. Among the chief suspects in the murder was the woman’s estranged common-law husband, Douglas Beamish, who was living nearby in his parents’ home. Among the chief suspects in the murder was the woman’s estranged common-law husband, Douglas Beamish, who was living nearby in his parents’ home. Royal Canadian Mounted Police had no evidence linking Beamish to the crime. Royal Canadian Mounted Police had no evidence linking Beamish to the crime. During the search for the victim’s body, however, the Mounties discovered a plastic bag containing a leather jacket with blood stains that matched the victim’s blood. During the search for the victim’s body, however, the Mounties discovered a plastic bag containing a leather jacket with blood stains that matched the victim’s blood.

81 Snowball the Cat: Prince Edward Island, Canada The jacket also contained 27 strands of white hair, which forensic investigators determined were from a cat. The jacket also contained 27 strands of white hair, which forensic investigators determined were from a cat. The Mounties remembered a white cat named Snowball living in Beamish’s parents’ home. The Mounties remembered a white cat named Snowball living in Beamish’s parents’ home. The trick was to prove the cat hair found in the jacket was Snowball’s. The trick was to prove the cat hair found in the jacket was Snowball’s.

82 “Meow Plex”: Cat STR

83 Angiosperm Witness for the Prosecution A young woman was murdered in Phoenix, Arizona, and a pager found at the scene of the crime led the police to a prime suspect. A young woman was murdered in Phoenix, Arizona, and a pager found at the scene of the crime led the police to a prime suspect. He admitted picking up the victim, but claimed she had robbed him of his wallet and pager. He admitted picking up the victim, but claimed she had robbed him of his wallet and pager. The forensic squad examined the suspect's pickup truck and collected pods later identified as the fruits of the Palo Verde tree (Cercidium spp.). The forensic squad examined the suspect's pickup truck and collected pods later identified as the fruits of the Palo Verde tree (Cercidium spp.).

84 Angiosperm Witness for the Prosecution One detective went back to the murder scene and found several Palo Verde trees, one of which showed damage that could have been caused by a vehicle. One detective went back to the murder scene and found several Palo Verde trees, one of which showed damage that could have been caused by a vehicle. The detective's superior officer innocently suggested the possibility of linking the fruits and the tree by using DNA comparison. The detective's superior officer innocently suggested the possibility of linking the fruits and the tree by using DNA comparison. A geneticist at the University of Arizona in Tucson agreed to take on the case. A geneticist at the University of Arizona in Tucson agreed to take on the case. Established evidence that individual Palo Verde trees have unique patterns of DNA. Established evidence that individual Palo Verde trees have unique patterns of DNA. It was then a simple matter to link the pods from the suspect's truck to the damaged tree at the murder scene and obtain a conviction. It was then a simple matter to link the pods from the suspect's truck to the damaged tree at the murder scene and obtain a conviction.

85 Viral DNA/RNA Evidence Convicts Doctor Dr. Richard Schmidt had an extramarital affair with his nurse, Janice Trahan. Dr. Richard Schmidt had an extramarital affair with his nurse, Janice Trahan. The relationship terminated when the doctor refused to leave his wife. The relationship terminated when the doctor refused to leave his wife. The doctor and nurse continued their working relationship, with the nurse allowing the doctor to continue to administer a series of Vitamin B-12 shots. The doctor and nurse continued their working relationship, with the nurse allowing the doctor to continue to administer a series of Vitamin B-12 shots.

86 Viral DNA/RNA Evidence Convicts Doctor The nurse’s health began to deteriorate shortly after one treatment and she received notification that she had contracted HIV and hepatitis. The nurse’s health began to deteriorate shortly after one treatment and she received notification that she had contracted HIV and hepatitis. Analysis of HIV strain from nurse closely resembled that of a strain from one of the doctor’s patients. Analysis of HIV strain from nurse closely resembled that of a strain from one of the doctor’s patients. The doctor was charged and convicted to attempted second degree murder. The doctor was charged and convicted to attempted second degree murder. He was sentenced to 50 years of hard labor. He was sentenced to 50 years of hard labor.

87 The Remains Of The Evangelist Luke Luke was born in Antioch, Roman province of Syria Luke was born in Antioch, Roman province of Syria Died in Thebes, Greece, at age of 84, around 150 AD Died in Thebes, Greece, at age of 84, around 150 AD Buried in Thebes but moved to Constantinople around 338 AD Buried in Thebes but moved to Constantinople around 338 AD Body moved to Padua, Italy, sometime before 1177 AD Body moved to Padua, Italy, sometime before 1177 AD

88 The Wandering Saint

89 Analysis Of The Remains Removed two teeth and extracted DNA Removed two teeth and extracted DNA Isolated control region of mitochondrial DNA and cloned it Isolated control region of mitochondrial DNA and cloned it Compared sequences from body to sequences of DNA from Compared sequences from body to sequences of DNA from Ancient and modern Greeks Ancient and modern Greeks Ancient and modern Turks Ancient and modern Turks Ancient and modern Syrians Ancient and modern Syrians

90 Teeth Removed From The Religious Relic: The body of St. Luke?

91 Is This St. Luke? The body is right age The body is right age The body is not Greek The body is not Greek Highest probability is that the body belonged to a Syrian but it is very difficult to tell Syrians from Turks Highest probability is that the body belonged to a Syrian but it is very difficult to tell Syrians from Turks


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