1. Forensic Serology Identification Using Blood Groups

2. Forensic Serology Serology – term used to describe a broad range of laboratory tests using reactions of blood serum and body fluid (including saliva, semen, urine, and blood) The serology section of a forensic laboratory may deal with any or all of the following: blood typing characterization of unknown blood stain patterns for crime reconstruction paternity testing semen identification in rape cases DNA techniques used for identification Due to funding & time needed for DNA analysis, many labs focus on basic serology procedures

3. Blood Facts The average adult has about FIVE liters of blood inside of their body, which makes up 7-8% of their body weight. Blood is living tissue that carries oxygen and nutrients to all parts of the body, and carries carbon dioxide and other waste products back to the lungs, kidneys and liver for disposal. It also fights against infection and helps heal wounds, so we can stay healthy. There are about one billion red blood cells in two to three drops of blood. For every 600 red blood cells, there are about 40 platelets and one white cell.

4. The Composition of Blood Blood is a mixture of many components: cellsinorganic substances (salts) enzymeswater proteins 55 % of blood content is plasma – mostly water and substances dissolved in it Most of the solid materials (by weight, 45%) are cells

5. What makes up our blood? RED BLOOD CELLS ( Erythrocytes ) – The most abundant cells in our blood; they are produced in the bone marrow and contain a protein called hemoglobin that carries oxygen to our cells. WHITE BLOOD CELLS ( Leukocytes ) – They are part of the immune system and destroy infectious agents called pathogens. PLASMA – This is the yellowish liquid portion of blood that contains electrolytes, nutrients and vitamins, hormones, clotting factors, and proteins such as antibodies to fight infection. PLATELETS ( Thrombocytes ) – The clotting factors that are carried in the plasma; they clot together in a process called coagulation to seal a wound and prevent a loss of blood.

6. Blood Terminology ABO blood groups—based on having an A, B, both or no antigens on red blood cells Rh factor—may be present on red blood cells ; positive if present and negative if not Antigen—a substance that can stimulate the body to make antibodies. Certain antigens ( proteins ) found in the plasma of the red blood cell’s membrane account for blood type. Antibody—a substance that reacts with an antigen Agglutination— clumping of red blood cells; will result if blood types with different antigens are mixed

7. Blood Antigens On the surface of red blood cells are chemical structures (proteins) called antigens The presence of antigens allow a living system to recognize foreign biological substances Antigens also impart specific characteristics to the red blood cells. These characteristics can be partly used to identify individuals Human red blood cells have more than 15 different antigen types that have been discovered

8. What are blood types? http://learn.genetics.utah.edu/units/basics/blood/types.cfm There are 3 alleles or genes for blood type: A, B, & O. Since we have 2 genes, there are 6 possible combinations. Blood Types AA or AO = Type A BB or BO = Type B OO = Type O AB = Type AB

9. Blood Typing When blood containing a specific antigen is mixed with blood containing the corresponding antibodies, the blood clots The clots can then be removed by the host system http://learn.genetics.utah.edu/units/basics/blood/typ es.cfm

10. Population Distribution of Blood Types in the U.S. TypePercent O A B AB 45 40 11 4

11. Rh Factors Scientists sometimes study Rhesus monkeys to learn more about the human anatomy because there are certain similarities between the two species. While studying Rhesus monkeys, a certain blood protein was discovered. This protein is also present in the blood of some people. Other people, however, do not have the protein. The presence of the protein, or lack of it, is referred to as the Rh (for Rhesus) factor. If your blood does contain the protein, your blood is said to be Rh positive (Rh+). If your blood does not contain the protein, your blood is said to be Rh negative (Rh-). A+ A- B+ B- AB+ AB- O+ O- http://www.fi.edu/biosci/blood/rh.html

12. Further Broken Down

13. Blood Transfusions A blood transfusion is a procedure in which blood is given to a patient through an intravenous (IV) line in one of the blood vessels. Blood transfusions are done to replace blood lost during surgery or a serious injury. A transfusion also may be done if a person’s body can't make blood properly because of an illness. Who can give you blood? People with TYPE O blood are called Universal Donors, because they can give blood to any blood type. People with TYPE AB blood are called Universal Recipients, because they can receive any blood type. Rh +  Can receive + or - Rh -  Can only receive - Universal Donor Universal Recipient

14. BLOOD SPATTER ANALYSIS What to do with blood that’s been collected

15. What does the abbreviation BPA represent? Bloodstain Pattern Analysis What can an investigator learn from the analysis of a blood spatter?  Type and velocity of weapon  Number of blows  Handedness of assailant (right or left-handed)  Position and movements of the victim and assailant during and after the attack  Which wounds were inflicted first  Type of injuries  How long ago the crime was committed  Whether death was immediate or delayed http://www.crimescenetwo.com/img/popup/book2p2.jpg How does a blood droplet form.

16. Forensic Characterization of Bloodstains Three questions that must be answered by the forensic investigator: 1) Is it blood? (most of these detect heme) Kastle-Meyer Test Hemastix (o-tolidine, TMB) Luminol Test 2) Is it human blood? Precipitin Test 3) Can it be associated with an individual? -look at blood type, alcohol content, and drugs present

17. Light Source Investigators will first examine the crime scene to look for areas that may contain blood. They may use a high-intensity light or UV lights to help them find traces of blood as well as other bodily fluids that are not visible under normal lighting conditions. How is blood evidence detected at a crime scene? Blood Reagent Tests These tests, referred to as presumptive tests, are used to detect blood at crime scenes based upon the properties of hemoglobin in the blood. Further tests at the crime lab can determine if it is human blood or not. HemaStix

18. Is it Blood? Tests Kastle-Meyer Test –Inexpensive –Easy to perform –Add H2O2 to blood, Heme breaks apart, add phenolphthalein to show pink color –Quick results –Provides evidence if red spots found at a crime scene are actually blood Other substances (vegetables) can give a positive result, must be careful

19. Is it Blood? Tests Hemastix/ Hematest tablet –This test involves a plastic strip with a reagent-treated filter paper tab at the end that contains Tetramethylbenzidine (TMB) and hydrogen peroxide (H 2 O 2 ) –Moisten a cotton swab with distilled water, touch the swab to the stain and place the swab directly onto the reagent tab on the strip –The reagent tab is originally yellow and undergoes a color change to green or blue- green indicating the presumption of blood

20. Luminol Red blood cells contain hemoglobin (Hb) – the protein responsible for transporting oxygen Each Hb contains four iron (Fe) containing hemes Wherever the luminol touches blood, it glows, and the glow is bright enough to be photographed Heme structure Scientists usually use luminol as a last resort because it can damage DNA evidence in blood

21. Precipitin Test Blood of every species contains different proteins, and blood from one species will not accept blood from another -test is time sensitive, but does work on small traces of blood

22. LCV or Leuco Crystal Violet, is one type of chemical process that is used for blood enhancement. Using this test helps to make the blood evidence more visible so it can be photographed and analyzed. Fluorescein This chemical is also capable of detecting latent or old blood, similar to luminol. It is ideal for fine stains or smears found throughout a crime scene. After the solution has been sprayed onto the substance or area suspected to contain blood, a UV light and goggles are used to detect any illuminated areas, which appear greenish-white if blood is present. It may also react to many of the same things as luminol (copper and bleach).

23. Bloodstain Pattern Analysis Terms Spatter – Bloodstains created from the application of force to the area where the blood originated. Origin/Source – The place from where the blood spatter came from or originated. Angle of Impact – The angle at which a blood droplet strikes a surface. Parent Drop Spines Satellite Spatters Parent Drop – The droplet from which a satellite spatter originates. Satellite Spatters – Small drops of blood that break of from the parent spatter when the blood droplet hits a surface. Spines – The pointed edges of a stain that radiate out from the spatter; can help determine the direction from which the blood traveled.

24. Passive Bloodstains –Patterns created from the force of gravity –Drop, series of drops, flow patterns, blood pools, etc. Projected Bloodstains –Patterns that occur when a force is applied to the source of the blood –Includes low, medium, or high impact spatters, cast- off, arterial spurting, expiratory blood blown out of the nose, mouth, or wound. Transfer or Contact Bloodstains –These patterns are created when a wet, bloody object comes in contact with a target surface ; may be used to identify an object or body part. –A wipe pattern is created from an object moving through a bloodstain, while a swipe pattern is created from an object leaving a bloodstain. Images from http://www.bloodspatter.com/BPATutorial.htm Types of Bloodstain Patterns

25. Projected Bloodstain Analysis Two Important Determinations: a. direction of splatter b. angle of impact with surface