8-1 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Chapter 8 Forensic Serology Courtesy of C. Fanning

8-2 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Until Karl Landsteiner discovered blood typing in 1901, blood transfusions often ended in failure – sometimes causing the blood to clot and causing instantaneous death. Out of Landsteiner’s work came the classification system called the A-B-O System. Blood Typing

8-3 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein By 1937, the Rh factor was discovered and shortly thereafter numerous other blood factors or groups were discovered. More than 100 different blood factors have been identified. Until the early 1990s, forensic scientists focused on blood factors as the best way to link to blood to an individual. Blood Typing

8-4 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Nature of Blood The word blood refers to a highly complex mixture of cells, enzymes, proteins, and inorganic substances. Plasma, which is the fluid portion of blood, is composed principally of water and makes up 55% of blood content. Red blood cells (erythrocytes), white blood cells (leukocytes), and platelets are the solid materials suspended in plasma and make up the remaining 45% of blood content.

8-5 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Blood Typing More than 15 blood antigen systems have been identified, but the A-B-O and Rh systems are the most important. Antigens, usually proteins, are located on the surface of red blood cells and are responsible for blood-type characteristics. An individual that is type A has A antigens on his/her red blood cells, type B has B antigens, AB has both A and B antigens, and type O has neither A nor B antigens.

8-6 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Blood Typing Blood TypeAntigens on RBCsAntibodies in Serum AAAnti-B BBAnti-A ABA and BNeither Anti-A or Anti-B ONeither A or BBoth Anti-A and Anti-B

8-7 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein

8-8 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Blood Typing Blood Type Distribution in US A42% B12% AB3% O43% Rh + 84% Rh - 16% Type O - is considered the universal donor Type AB + is the universal recipient Type AB - is the rarest blood type (1%) Type O + is the most common blood type (38%)

8-9 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Blood Typing Rh factor is determined by the presence of another antigen, the D antigen. People having the D antigen are Rh positive; those not having the antigen are Rh negative.

8-10 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Blood Typing For every antigen there is a specific antibody that will react with it to form clumps known as agglutination. Thus, if serum containing anti-B is added to red blood cells carrying B antigen, they will immediately react and the blood will clot.

8-11 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Serology Serology is used to describe a broad scope of laboratory tests that use specific antigen and serum antibody reactions. The identity of each of the four A-B-O blood groups can be established by testing the blood with anti-A and anti-B sera. Anti-A Serum + Whole Blood Anti-B Serum + Whole Blood Antigen Present Blood Type +-AA -+BB ++A and BAB --NeitherO

8-12 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein The identity of each of the four A-B-O blood groups can also be established by testing the blood with known A and B antigens. A Cells + Blood B Cells + Blood Antibody Present Blood Type +-Anti-AB -+Anti-BA ++ Both Anti-A and Anti-B O -- Neither Anti-A or Anti-B AB Serology

8-13 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Serology Antigen-Antibody Reaction The concept of specific antigen–antibody reactions has been applied to immunoassay techniques for the detection of drugs of abuse in blood and urine. A number of immunological assay techniques are commercially available for detecting drugs through antigen- antibody reaction.

8-14 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Immunoassay One such technique, the enzyme-multiplied immunoassay technique (EMIT), is used by toxicologists because of its speed and high sensitivity for detecting drugs in urine. In a typical EMIT analysis, antibodies that will bind to a specific drug are added to the subject’s urine. Most frequent uses of EMIT is to test for marijuana use. Cannot tell WHEN marijuana was used because some individuals may test positive up to 10 days after the last use.

8-15 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Immunoassay Other immunoassay procedures are also available, such as radioimmunoassay (RIA), which uses drugs labeled with radioactive tags. RIA is not totally specific for any drug. May give a false-positive test reaction because drugs with a similar chemical structure may cross react.

8-16 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Antigen-Antibody Reaction When an animal, such as a rabbit or mouse, is injected with an antigen its body will produce a series of different antibodies, all of which are designed to attack some particular site on the antigen of interest.

8-17 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Antigen-Antibody Reaction This collection of antibodies is known as polyclonal antibodies. Alternately, a more uniform and specific collection of antibodies designed to combine with a single antigen site can be manufactured. Such antibodies are known as monoclonals.

8-18 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Forensics of Blood The criminalist must be prepared to answer the following questions when examining dried blood: 1. Is it blood? 2. From what species did the blood originate? 3. If the blood is of human origin, how closely can it be associated to a particular individual?

8-19 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Forensics of Blood Determination of blood is best made by a preliminary color test. A positive result from the Kastle-Meyer color test is highly indicative of blood. Hemoglobin causes a deep pink color. May also turn pink in the presence of some vegetable matter, like potatoes and horseradish. Hemastix are also useful presumptive tests for blood. When moistened and placed in contact with bloodstain, it turns green.

8-20 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Testing for Blood Alternatively, the luminol test is used to search out trace amounts of blood located at crime scenes. Luminol produces light (luminescence) in a darkened area. Courtesy of C. Fanning Luminol with false positive (bleach) Courtesy of C. Fanning

8-21 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Testing for Blood A relatively new product, Bluestar, can now be used in place of luminol. Bluestar is easy to mix in the field and does not have to be observed in complete darkness. Courtesy of C. Fanning

8-22 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Testing for Blood Both Luminol and Bluestar are extremely sensitive and do not interfere with any subsequent DNA testing.

8-23 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Testing for Blood Microcrystalline tests, such as the Takayama and Teichmann tests, depend on the addition of specific chemicals to the blood so that characteristic crystals will be formed. Less sensitive than color tests and are more susceptible to interference from contaminants present in the stain.

8-24 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Testing for Blood Once the stain has been characterized as blood, the precipitin test will determine whether the stain is of human or animal origin. The precipitin test uses antisera normally derived from rabbits that have been injected with the blood of a known animal to determine the species origin of a questioned bloodstain.

8-25 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Testing for Blood Strengths of the precipitin test include the fact that it is very sensitive, it requires only a small amount of blood for testing and human blood stains dried for years may still give a positive reaction. Tissue extracts from mummies 4,000-5,000 years old have still given positive reactions with this test!

8-26 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Once it has been determined that the bloodstain is of human origin, an effort must be made to associate or dissociate the stain with a particular individual. DNA analysis has allowed forensic scientists to associate blood to a single individual. Testing for Blood

8-27 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Principles of Heredity All of the antigens and proteins (hemoglobin and antibodies) related to blood typing and the detection of blood are genetically controlled traits. Determining the identity of these traits, provides us with a picture of how one individual compares to or differs from another.

8-28 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Principles of Heredity Genes are the basic unit of heredity, consisting of a DNA segment located on a chromosome. Chromosomes are threadlike structures in the cell nucleus, along which the genes are located.

8-29 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Principles of Heredity Just as chromosomes come together in pairs (one from each parent), so do genes. Alternative forms of genes are known as alleles. An individual’s blood type is determined by three genes, designated as A, B and O.

8-30 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Principles of Heredity Two similar alleles is said to be homozygous. ◦AA, BB, OO Two different alleles is said to be heterozygous. ◦AO, BO, AB Because both genes are expressed (Type AB), the trait is considered to be codominant.

8-31 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Principles of Heredity A pair of allele genes together constitutes the genotype of the individual. The physical expression of the genes is the phenotype. However, there is no known lab test to determine a person’s genotype. ◦For example, we can determine a person might have Type A blood (phenotype), but that test does not determine if the genotype is AA or AO. ◦Have to study genotypes of both parents.

8-32 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Heredity and Paternity Paternity testing has historically involved the A-B-O blood typing system, along with blood factors other than A-B-O. Currently, paternity testing has implemented DNA test procedures that can raise the odds of establishing paternity beyond 99 percent.

8-33 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Testing for Seminal Stains Many of the cases sent to a forensic laboratory involve sexual offenses, making it necessary to examine exhibits for the presence of seminal stains. The best way to locate and at the same time characterize a seminal stain is to perform the acid phosphatase (an enzyme secreted into seminal fluid) color test. ◦A purple color indicates acid phosphatase enzyme.

8-34 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Testing for Seminal Stains Semen can be unequivocally identified by either the presence of spermatozoa or of p30, a protein unique to seminal plasma. Forensic scientists can successfully link seminal material to an individual by DNA typing.

8-35 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Rape Evidence The rape victim must undergo a medical examination as soon as possible after the assault. At that time the appropriate items of physical evidence including clothing, hairs, and vaginal and rectal swabs can be collected for subsequent laboratory examination. All outer and undergarments should be carefully removed and packaged separately in paper (not plastic) bags. Bedding, or the object upon which the assault took place, may also be carefully collected.

8-36 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Rape Evidence If a suspect is apprehended within 24 hours of the assault, it may be possible to detect the victim’s DNA on the male’s underwear or on a penile swab of the suspect. Items routinely collected from the suspect include all clothing, pubic hair, head hair, penile swab, and a blood sample or buccal swab for DNA typing. The forceful physical contact between victim and assailant may result in a transfer of such physical evidence of blood, semen, saliva, hairs, and fibers.