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2009©Forensic Science Today Serology Body fluids and the stains they leave at crime scenes
2009©Forensic Science Today Common Types of Serology Commonly found rape cases are: Blood Hair Sperm
2009©Forensic Science Today History of Blood Typing 1901- Karl Landsteiner, recognized differences in human blood Received Nobel Prize in 1929 Critical in blood transfusions A-B-O classification system Rh factor in blood was demonstrated in 1937 More than 100 different blood factors are known today.
2009©Forensic Science Today True or False NNo two individuals, except for identical twins, could be expected to have the same combination of blood factors.
2009©Forensic Science Today Prior to 1990, A-B-O system provided the best means for forensic scientists to link blood to an individual. What changed in 1990?
2009©Forensic Science Today Components of Blood CCellular-Solid materials suspended in plasma that makes up 45% of “blood” Red Blood Cells (RBC)-erythrocytes White Blood Cells (WBC)-leukocytes Platelets PPlasma – 55%- fluid portion of unclotted blood-mostly water Antibodies Enzymes Proteins Serum= liquid that separates from the blood when a clot is formed
2009©Forensic Science Today Blood Stains on Victim’s Jeans Sections removed & initialed for testing
2009©Forensic Science Today Forensic Characterization of Bloodstains Is it blood? From what species did it originate? If the blood is of human origin, how closely can it be associated to a particular individual?
2009©Forensic Science Today Species Identification Prior to 1990, double immuno- diffusion plate was used for species identification of blood stains. Today scientists simply test using DNA techniques
2009©Forensic Science Today Techniques to Visualize Kastle-Meyer – uses H 2 O 2 + phenolphthalein to produce a bright pink color in the detection of peroxidase activity in blood Leucomalachite green. Leucomalacite green is dropped on the suspect stain. A positive blood result will immediately turn the swab greenish- blue.
2009©Forensic Science Today More Visualization Tetramethylbenzidine- test by placing drops on a suspect stain. A positive reaction is indicated by an intense blue color. Luminol- Luminol is also a field test that you may have seen on one of the forensic investigation television shows. It involves spraying the chemical onto the suspected bloodstain and viewing it in total darkness. If blood is present, it will begin to luminesce (glow a whitish-blue) within 5 seconds.
2009©Forensic Science Today Luminol Test Extremely Sensitive- capable of detecting bloodstains diluted up to 300,000 times Large areas are sprayed and viewed in darkened areas for emission of light Does not interfere with subsequent DNA testing http://www.flickr.com/photos/jackofspades/4376209354/ http://www.flickr.com/photos/jackofspades/4376209354/ Figure 12-5 p. 337 Saferstein Criminalistics, 2004
2009©Forensic Science Today A Bloody Knife from a Homicide Scene.
2009©Forensic Science Today From what species did it originate? Preciptin Test >Very sensitive >Requires only a small sample >Even dried bloodstains from 10-15 years ago can be tested. >Positive test results even in diluted samples Gel diffusion See pp. 338-339 Saferstein, Criminalistics, 2004.
2009©Forensic Science Today Applications of Genotyping Blood Factors No direct relevance to Criminal Investigations Paternity Testing Blood type may clear a suspect Example: Child is type AB Mother is type AB Suspected Father is type O Draw the Punnett Square.
2009©Forensic Science Today Rape Statistics http://www.rainn.org/statistics http://www.rainn.org/statistics
2009©Forensic Science Today Forensic Characterization of Semen Locate the stain and screen for semen with the acid phosphatase color test Acid phosphatase is an enzyme present in high concentrations in semen Suspect stain is transferred to filter paper; reagent is added. If semen is present, sample will fluoresce under UV light within 30 seconds. http://www.houstonpi.com/sementrace/videos.html http://www.houstonpi.com/sementrace/videos.html
2009©Forensic Science Today Microscopic Examination Semen can be identified by the presence of spermatazoa @ 400x magnification
2009©Forensic Science Today Challenges for the Microscopist Sample collection: Sperm bind tightly to cloth materials, are extremely brittle when dry, and disintegrate if the stain is washed or rubbed against another object Oligospermia – abnormally low sperm count (prefix Oligo means “just a few or scant” Aspermia - absence of sperm or sterility (partly due to growing popularity of vasectomies)
2009©Forensic Science Today p30 or Prostate Specific Antigen Protein discovered in 1970’s Unique to seminal plasma See Criminalistics pp. 351 & 352 Figure 12-6 and Figure 12-17 for PSA testing by precipitation and electrophoresis If semen is present, DNA testing is used to link seminal material to an individual. More later....
2009©Forensic Science Today Collection of Rape Evidence Forceful physical contact between victim and assailant may result in the transfer of hair, fibers, blood, and semen (Locard’s Exchange Principle) Carefully package all outer garments and undergarments separately in PAPER bags. Victim should stand on paper while undressing so that any loose fibers can be collected for analysis. Collect bedding, if appropriate
2009©Forensic Science Today Collection of Rape Evidence Disposable latex gloves are essential for handling evidence! DNA may be transferred through perspiration. Investigators must avoid direct personal contact with evidence.
2009©Forensic Science Today Victim needs a medical exam ASAP! Evidence collection kit includes Pubic combings & standard/reference samples External genital skin areas Vaginal swabs & smear Cervix swabs Rectal swabs & smear Oral swabs & smear Head hairs Blood sample Fingernail scrapings All clothing Urine specimen (for drug testing e.g. Rohypnol, GHB) Swab of any area that may have assailant’s saliva for DNA testing See Saferstein, Criminalistics, 2004, p. 353
2009©Forensic Science Today Evidence from Suspect, if apprehended All clothing Pubic Hair combings Pulled head and pubic hair standard/reference samples Penile swab taken within 24 hours after assault Blood sample or buccal swab for DNA testing
2009©Forensic Science Today DNA Testing Extremely sensitive- characterization possible with only 1 billionth of a gram of sample
2009©Forensic Science Today Timing SSperm can survive up to 4-6 hours in the vaginal cavity of a living female. Time of sexual attack may be determined. NNonmotile sperm may be found up to 3 days after intercourse. AAcid phosphatase can be detected in the vaginal cavity for up to 48 hours after intercourse. p30 can be detected for 24 hours.
Forensic Characterization of Semen The presence of seminal stains is important in crimes involving sexual offenses. Two steps: 1. Stains must be located.
Semen & Rape. List the laboratory tests necessary to characterize seminal stains Explain how suspect blood and semen stains are properly preserved.
The term serology is used to describe a broad scope of laboratory tests that use specific antigen and serum antibody reactions. In addition to blood, other.
Unit 5 Forensic Serology. Blood and Forensics Karl Landsteiner in 1901 discovered that not all human blood was the same He came up with a classification.
Forensic Characterization of Semen. Secretors Eighty percent of the population are secretors. Their blood- type antigens are found in high concentration.
Forensic Characterization of Semen The presence of seminal stains is important in crimes involving sexual offenses. The presence of seminal stains is important.
Forensic Serology Criminalistics Chapter 12. Karl Landsteiner First person to recognize that all human blood is not the same First person to recognize.
Chapter 9 Forensic Serology Courtesy of C. Fanning.
8-1 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Chapter 8 Forensic.
Identification of Blood and Biologicals. Is it Blood? We will spend a lot of time characterizing the patterns that blood makes as a result of traumatic.
BLOODSTAIN PATTERNS. Interpretation of Bloodstains The location, distribution, and appearance of bloodstains and spatters are useful for reconstructing.
8-1 PRENTICE HALL ©2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE An Introduction By Richard Saferstein FORENSIC SEROLOGY Chapter.
Forensic Serology YouTube - The Sam Sheppard case YouTube - The Sam Sheppard case.
12.2 Notes - Techniques. Objectives Understand the concept of antigen- antibody interactions and how it is applied to species identification and drug.
Forensic Serology Chapter 8. Blood Components Plasma--fluid part of blood unclotted blood Plasma--fluid part of blood unclotted blood Erythrocytes—hold.
Serology The study of body fluids. Serology-Definition The study of antigen/antibody reaction The study of biological fluids Blood, sweat, tears, saliva,
Forensic Serology Identification Using Blood Groups.
8-1 PRENTICE HALL ©2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE An Introduction By Richard Saferstein Chapter 8.
Serology Study of bodily fluids using antigen-antibody reactions.
IMMUNOASSY TECHNIQUES, ETC. Ch. 8 Serology. For Review: Antigen: A substance which, when put into a body, stimulate the body to produce antibodies against.
The study of antigen-antibody reactions. The Nature of Blood-1 Blood is a complex mixture of: Cells Enzymes Proteins Fluid Portion is called Mostly water.
Serology in Practice Sexual Crimes. Characteristics of Semen Search for semen includes corpse, victim, undergarments, bed sheets, mattresses, carpeting,
1 Forensic Science Chapter 12: Forensic Serology.
Chapter 9. Blood and Physiological Fluid Evidence: Evaluation and Initial Examination How Biological Evidence Analysis Has Changed Because of DNA Typing.
12- PRENTICE HALL ©2007 Pearson Education, Inc. Upper Saddle River, NJ CRIMINALISTICS An Introduction to Forensic Science, 9/E By Richard Saferstein.
COLLECTION OF RAPE EVIDENCE Serology Unit. Summary Rape is often associated with many different forensic crime scenes 293,066 crimes are reported annually.
College Forensics: Project Advance Chapter 12: Forensic Serology.
Forensic Serology Blood Most common blood types: O Rh positive percent O Rh negative percent A Rh positive percent A Rh negative ---
Forensic Serology Ch. 12. Blood Baby...cute Nature of Blood The word ‘blood’ refers to a highly complex mixture of cells, enzymes, proteins, and inorganic.
Forensic Serology Identification Using Blood Groups This presentation contains graphic pictures.
Forensic Serology Identification Using Blood Groups This presentation contains graphic pictures. Downloaded from
Chapter 12 Forensic Serology. Forensic Serology Introduction 1901, Karl Landsteiner found blood to be distinguishable by group –Led to the classification.
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0 Blood That an antibody and an antigen of different types will agglutinate, or clump, when mixed together. That the significance of the evidence depends.
Forensic Biology (Serology) FRSC 2001 Professor Bensley Alfred State College.
Identification of Biological Fluids and Stains. Summary Semen Saliva Urine Feces Vomit.
FORENSIC IMPLICATIONS OF THE CIRCULATORY SYSTEM Blood found at a crime scene can be used to identify the victim or the perpetrator. Blood type is a class.
Identification and Characterization of Blood and Bloodstains.
Forensic Serology Blood, Semen, vaginal fluid, and saliva.
Serology. Study of bodily fluids: blood, semen, saliva, urine, vaginal secretions, and excrement DNA can also be collected from these samples.
DETERMINATION OF BLOOD 12.3 NOTES –. OBJECTIVES List and describe forensics tests used to characterize a stain as blood.
Blood and Blood Spatter Serology Blood Spatter Analysis.
Ch 12- Forensic Serology Blood types and their antigens and antibodies. Agglutination. Whole blood typing. Characterizing a stain as blood. Significance.
Forensic Serology. Blood l l A complex mixture of cells, enzymes, proteins & inorganic substances l l Fluid portion of blood is called the plasma (55%
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