Forensic Serology Chapter 12 Learning Objectives:

Forensic Serology Chapter 12 Learning Objectives:
List the A-B-O antigens and antibodies found in the blood for each of the four blood types: A, B, AB, and O. Explain why agglutination occurs. Explain how blood is typed.

Describe tests used to characterize a stain as blood. Explain the significance of the precipitin test to forensic serology. Explain the differences between monoclonal and polyclonal antibodies.

Define chromosome and gene. How is the Punnett square used to determine the genotypes and phenotypes of offspring? List the laboratory tests necessary to characterize seminal stains.

Explain how suspect stains are to be properly preserved for laboratory examination. Describe the collection of physical evidence related to a rape investigation.

History of Forensic Serology
Chapter 12 History of Forensic Serology 1901 Karl L?????? discovered the typing of blood. From his work came the A-B-O system Impact on blood transfusion successes Nobel Prize Organization website-

Chapter 12 History of Forensic Serology 1901 Karl Landsteiner discovered the typing of blood. From his work came the A-B-O system Impact on blood transfusion successes Nobel Prize Organization website-

HISTORY He was awarded a Noble Prize for his work.

Chapter 12 History of Forensic Serology 1st significance to forensics: Blood factors are controlled genetically- potential for ???term for 1 person?? 2nd high frequency of blood stains found at crime scenes Blood factor characterization is now being replaced with DNA evidence

Chapter 12 History of Forensic Serology 1st significance to forensics: Blood factors are controlled genetically- potential for individualization 2nd high frequency of blood stains found at crime scenes Blood factor characterization is now being replaced with DNA evidence

Chapter 12 History of Forensic Serology 1937 Rh factor discovered Rh=?? At present- more than 100 different blood factors are known

Chapter 12 History of Forensic Serology 1937 Rh factor discovered- Rhesus monkeys At present- more than 100 different blood factors are known

Forensic Applications of Serology
Homicides Sexual Assaults Assaults Robberies Kidnappings Shootings (today DNA testing generally preferred)

The Nature of Blood The term blood refers to a highly complex mixture of cells, enzymes, proteins, and inorganic substances. The fluid portion of blood is called p????? It is composed primarily of water and accounts for 55% of blood content.

The Nature of Blood The term blood refers to a highly complex mixture of cells, enzymes, proteins, and inorganic substances. The fluid portion of blood is called plasma. It is composed primarily of water and accounts for 55% of blood content.

Blood Solids Suspended in the plasma are these solid materials:
Red blood cells or e???? White blood cells or l???? Platelets- T???? Red blood cells White blood cells Platelets

Blood Solids Suspended in the plasma are these solid materials:
Red blood cells or erythrocytes White blood cells or leukocytes Platelets- thrombocytes Red blood cells White blood cells Platelets

The Nature of Blood Chapter 12
Blood = cells, enzymes, proteins and inorganic substances

Chapter 12 See Blood Types Chart on p. 330
S????? is the yellowish liquid left if one adds fibrin (making the blood clot) and removing the clotted material RBC’s transport oxygen from the lungs to the body tissues RBC’s remove carbon dioxide from the tissues back to the lungs See Blood Types Chart on p. 330

Chapter 12 See Blood Types Chart on p. 330
Serum is the yellowish liquid left if one adds fibrin (making the blood clot) and removing the clotted material RBC’s transport oxygen from the lungs to the body tissues RBC’s remove carbon dioxide from the tissues back to the lungs See Blood Types Chart on p. 330

The Nature of Blood Chapter 12
Fluid portion = plasma (55% of blood) mainly water Cells suspended in plasma (45% of blood)

A???? A substance, usually a protein, on the surface of the red blood cell, that stimulates the body to produce antibodies against it. The A-B-O and the Rh systems are the most important.

ANTIGENS A substance, usually a protein, on the surface of the red blood cell, that stimulates the body to produce antibodies against it. The A-B-O and the Rh systems are the most important.

A????? Proteins found in the blood serum that destroy or inactivate a
specific antigen. The fundamental principle of blood typing is that for every antigen, there exists a specific a

ANTIBODY Proteins found in the blood serum that destroy or
inactivate a specific antigen. The fundamental principle of blood typing is that for every antigen, there exists a specific antibody.

Chapter 12 The Nature of Blood Antigens and Antibodies

The Nature of Blood Chapter 12 Antigens and Antibodies
Antibodies are normally “Bivalent” = two reactive sites (can attach to 2 different RBCs)

Name this term The clumping together of red blood cells by the action of an antibody.

AGGLUTINATION The clumping together of red blood cells by the action of an antibody.

The Nature of Blood Chapter 12 Antigens and Antibodies
Agglutination occurs when cells are cross-linked

 Microscopic view of normal red blood cells
Microscopic view of agglutinated red blood cells 

Neither anti-A nor anti-B
Blood Type Antigens on Red Blood Cells Antibodies in Serum ? A Anti-B B Anti-A AB Neither anti-A nor anti-B Neither A nor B Both anti-A and anti-B

Neither anti-A nor anti-B
Blood Type Antigens on Red Blood Cells Antibodies in Serum A Anti-B B Anti-A AB Neither anti-A nor anti-B O Neither A nor B Both anti-A and anti-B

The Nature of Blood Chapter 12 Blood Typing
Visit this site to learn more on blood typing: Visit to view some blood related pictures:

Immunoassay Techniques
Chapter 12 Immunoassay Techniques Antigen-antibody reactions: Detection of drugs in blood and urine How are antibodies that react to drugs made? Injection of a protein-drug combination into a rabbit, followed by collection of that rabbits blood serum (See Figure 12-3 on p. 333)

Chapter 12 Immunoassay Techniques Enzyme-multiplied immunoassay technique (EMIT)- quick and sensitive for detecting drugs in urine Screening urine of suspected marijuana smokers EMIT can detect less than one-millionth of a gram of THC-9-carboxylic acid (major THC metabolite)

Chapter 12 Immunoassay Techniques One problem with EMIT technique- positive results last up to 10 days after use (doesn’t tell you when the marijuana was smoked) Radioimmunoassay (RIA)- use of radioactive tags on drugs Both EMIT and RIA may give false positives to substances with similar chemical structures

Chapter 12 Immunoassay Techniques Visit this website for diagrams on Immunoassay procedures:

Chapter 12 Immunoassay Techniques Which?? Antibodies Forensic need for antibodies that are uniform in their composition and attack power Production of Monoclonal Antibodies (to study from text see Figure 12-4 on p. 335) Visit this site for diagram on the steps require to produce these antibodies:

Chapter 12 Immunoassay Techniques Monoclonal Antibodies Forensic need for antibodies that are uniform in their composition and attack power Production of Monoclonal Antibodies (to study from text see Figure 12-4 on p. 335) Visit this site for diagram on the steps require to produce monoclonal antibodies:

?????? ??????

antibody forming cells are isolated from the mouse's spleen
Legend: Mouse or rabbit is immunized by injection of an antigen X to stimulate production of antibodies targeted against X antibody forming cells are isolated from the mouse's spleen Fusing single antibody-forming cells + tumor cells grown in culture= hybridoma. Hybridomas make Large quantities of identical antibody molecules These antibodies are called "monoclonal antibodies" because they are produced by the identical offspring of a single, cloned antibody producing cell. Once a monoclonal antibody is made, it can be used as a specific probe to track down and purify the specific protein that induced its formation.

FORENSIC CHARACTERIZATION OF BLOODSTAINS
Is it blood? From what species did the blood originate? If the blood is of human origin, can it be associated to a particular individual?

SEROLOGY Selection of tests depends on Quantity Quality
Sufficient for testing Retain portion for Defense Quality Degradation of sample

Chapter 12 Forensic Characterization of Bloodstains Is it blood?
From what species did the blood originate If the blood is of human origin, how closely can it be associated to a particular individual?

Which?? color test- use a chemical phenolphthalein + hemoglobin + hydrogen peroxide = deep pink color False-positives from vegetable materials (from what???) Stop for minilab and try it!

Kastle-Meyer color test- use a chemical phenolphthalein + hemoglobin + hydrogen peroxide = deep pink color False-positives from vegetable materials (potatoes and horseradish) Stop for minilab and try it!

Is it blood? PRESUMPTIVE or CONFIRMATORY??? TEST FOR BLOOD
CAN HAVE FALSE POSITIVES VERY SENSIVIVE Phenolphthalein (Kastle-Meyer) color test H?????? strips based on peroxidase-like activity of the hemoglobin L?????? test reacts with heavy metals to glow in the dark iron, copper, chlorine

Is it blood? PRESUMPTIVE TEST FOR BLOOD CAN HAVE FALSE POSITIVES
VERY SENSIVIVE Phenolphthalein (Kastle-Meyer) color test Hemastix® strips based on peroxidase-like activity of the hemoglobin Luminol test reacts with heavy metals to glow in the dark iron, copper, chlorine

Hemastix®

Is it blood? PRESUMPTIVE TEST FOR BLOOD Luminol test
*extremely sensitive- bloodstains diluted up to 300,000 time can be detected *Will not interfer with DNA E

Is it blood? Not as sensitive Microcrystalline test – T and T?
CONFIRMATORY TEST FOR BLOOD Not as sensitive Microcrystalline test – T and T? Antibody tests – O???

Is it blood? Not as sensitive
CONFIRMATORY TEST FOR BLOOD Not as sensitive Microcrystalline test – Takayama and Teichmann tests Antibody tests - Ouchterlony

Antibody tests - Ouchterlony

Is It Human? P????? test – an antibody that reacts with its corresponding antigen to form a precipitate Human antiserum, dog, cat, bovine, deer, etc.

Is It Human? Precipitin test – an antibody that reacts with its corresponding antigen to form a precipitate Human antiserum, dog, cat, bovine, deer, etc.

Can this blood be associated to a particular individual?
MAYBE!?! Blood Type Distribution in the United States O A B AB ?%

Can this blood be associated to a particular individual?
MAYBE!?! Blood Type Distribution in the United States O A B AB 43% 42% 12% 03%

Key Terms for Blood Proteins
E?? – Proteins that act as catalysts for certain specific chemical reactions in the body. P?? – The existence of more than one form of a genetic trait. I?? – Multiple molecular forms of an enzyme, each having the same or very similar enzyme activity.

Blood Enzymes and Proteins
Enzymes – Proteins that act as catalysts for certain specific chemical reactions in the body. Polymorphism – The existence of more than one form of a genetic trait. Iso-enzymes – Multiple molecular forms of an enzyme, each having the same or very similar enzyme activity.

Separation of PGM Iso-enzymes Accomplished by Electrophoresis

PGM = phosphoglucomutase
All persons do not have the same PGM iso-enzymes 3 common variations: PGM: PGM1, PGM2-1 and PGM 2-1 PGM 1= 58% PGM % PGM 2 is in 6% See table 12-3 on p. 341 for other blood enzymes and proteins used to discriminate bloodstains

STATISTICS Frequency of one type
Multiplied by frequency of each other type Tells you HOW OFTEN the COMBINATION of types occurs in the general population Separated by race / ethnicity 0.10 X 0.10 X 0.10 = or 0.1% 1 in 1,000 persons

Stain Patterns of Blood
Visit this website for a tutorial before beginning blood patterns labs

Key Points from MacDonell Surface texture- the harder and less porous the surface, the less spatter results The direction of travel of blood striking an object can be determined from the stain’s shape

Key Points from MacDonell 3. It is possible to determine the impact angle of blood on a flat surface by measuring the degree of circular distortion. 4. The origin of a blood spatter in a two-dimensional configuration can be established by drawing straight lines through the long axis of several individual stains. The intersection or point of convergence of the lines represents the point from which the blood emanated.

Principles of Heredity
Transmission of Traits *Genes and Chromosomes

Transmission of Traits *Genes and Chromosomes Different genes are activated in different cells, creating the specific proteins that give a particular cell type its character.

Egg + Sperm = Zygote

HEREDITY ALLELE - one form of a trait
POLYMORPHIC - many forms of a trait HOMOZYGOUS - two copies of one trait HETEROZYGOUS - two forms of a trait GENOTYPE - pair of allele genes PHENOTYPE - outward characteristic of gene

Transmission of Traits *Sex Chromosomes

Punnett Squares **p and q are alleles **pp and pq and qq are genotypes Time to practice using Punnett Squares.

HEREDITY R? - only expressed when have homozygote
D? - expressed with either homozygote or heterozygote PATERNITY TESTING - Who are you? (who who - who who)

HEREDITY RECESSIVE - only expressed when have homozygote
DOMINANT - expressed with either homozygote or heterozygote PATERNITY TESTING - Who are you? (who who - who who)

Is it possible for the child to be the offspring of these two people?
HEREDITY PUNNET SQUARE Is it possible for the child to be the offspring of these two people?

FORENSIC CHARACTERIZATION OF SEMEN

COMPONENTS OF SEMEN Seminal Fluid SPERM CELLS White blood cells
Amino Acids Sugars Salts Ions Other Organic & Inorganic materials SPERM CELLS White blood cells Epithelial cells

THE SEARCH FOR STAINS

Blue Light Under certain conditions, semen (and some other body fluids) will fluoresce. Used to search bedding, clothing or crime scenes for possible semen evidence. P????? test for semen.

Blue Light Under certain conditions, semen (and some other body fluids) will fluoresce. Used to search bedding, clothing or crime scenes for possible semen evidence. Presumptive test for semen.

A?? P??? An enzyme secreted by the prostate gland into seminal fluid. concentrations are up to 400 times greater in seminal fluid than in any other body fluid. Presumptive test for semen (also found in vaginal fluid)

Acid Phosphatase An enzyme secreted by the prostate gland into seminal fluid. Acid phosphatase concentrations are up to 400 times greater in seminal fluid than in any other body fluid. Presumptive test for semen (also found in vaginal fluid)

P? S? A? Developed in the 1970’s It is a protein
It is found in seminal plasma is isolated, injected into a rabbit and the anti- antibodies can then be utilized Confirmatory test of presence of semen

Prostate Specific Antigen or p30
Developed in the 1970’s It is a protein It is found in seminal plasma p30 is isolated, injected into a rabbit and the anti-p30 antibodies can then be utilized Confirmatory test of presence of semen

A single ejaculation can release 2.5 to 6 milliliters of seminal fluid Each milliliter can contain 100 million or more spermatozoa, the male reproductive cells C?????? test for presence of semen

A single ejaculation can release 2.5 to 6 milliliters of seminal fluid Each milliliter can contain 100 million or more spermatozoa, the male reproductive cells Confirmatory test for presence of semen

Time for your own investigation- and to practice your microscope and camera skills
Get it focused-take an image- mark up with the labels on this slide

Spermatozoa Variations

S???? IDENTIFICATION AMYLASE ABO antigens Starch - Iodine Test
Presumptive for this ABO antigens

SALIVA IDENTIFICATION
AMYLASE Starch - Iodine Test Presumptive for saliva ABO antigens

Secretor Status Secretor – An individual who secretes his or her blood-type antigen(s) in body fluids (saliva, semen, vaginal secretions, and gastric juices). Approximately ??% of the population are secretors.

Secretor Status Secretor – An individual who secretes his or her blood-type antigen(s) in body fluids (saliva, semen, vaginal secretions, and gastric juices). Approximately 80% of the population are secretors.

OTHER BODY FLUIDS URINE FECES VOMITUS VAGINAL FLUIDS Urea, Creatinine
Urobilinogen VOMITUS pH VAGINAL FLUIDS Stain for Glycogen

RAPE INVESTIGATION Collect samples Body fluid swabs
Pubic hair combing/matted hair Pubic hair cuttings/known Vaginal/oral/anal swabs Vaginal/oral/anal smear slides Fingernail scrapings Buccal swab for known DNA

RAPE INVESTIGATION Collect clothing / evidence
Underwear Pants All other clothing Sheets As you get further away from the victim, the more room for doubt

Chapter Review Questions
Competition Time Get in teams of 2 Take out 1 piece of paper with both your names on it Turn to pages

Competition #1 p. 358 #2-20 EVEN only

Competition #3 p #22-40 EVEN only

Homework: Write out the questions AND answers for the odd numbered review questions and then **Write page numbers where answers for odd questions are found

Forensic Serology Chapter 12 Learning Objectives:

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