Chapter 8 Blood “Out damned spot! Out, I say Here’s the smell of the blood still, All the perfumed of Arabia will not Sweeten this little hand. Oh, Oh, Oh!” —William Shakespeare’s Lady Macbeth, in Macbeth Kendall/HUnt

Chapter 10 Blood You will learn: That an antibody and an antigen of different types will agglutinate, or clump, when mixed together. That the significance of the evidence depends on a characteristic’s relative occurrence in the population. Kendall/HUnt

Blood Determine whether a stain is blood. Chapter 10 Blood You will be able to: Determine whether a stain is blood. Determine whether a bloodstain is human or animal blood. Determine the blood type of a simulated bloodstain using the ABO/Rh system. Kendall/HUnt

Serology The examination and analysis of body fluids Chapter 10 Serology The examination and analysis of body fluids From 1950’s to 1980’s -- high importance With DNA -- now a matter of economics Serology is the examination and analysis of body fluids. A forensic serologist may analyze a variety of body fluids including saliva, semen, urine, and blood. From 1950 to the late 1980’s, forensic serology was a most important part of lab procedures. With the development of DNA techniques, more time, money, and significance was placed in developing DNA labs. However, with limited funds and the time required for DNA testing, most labs still use many of the basic serology testing procedures. Kendall/HUnt

Blood Characteristics Chapter 10 Blood Characteristics Plasma is the fluid portion of the blood (55%) Cells (45%) Erythrocytes are red blood cells. They are responsible for oxygen distribution. Leukocytes are the white blood cells; they are responsible for “cleaning” the system of foreign invaders. Platelets (proteins) are responsible for blood clotting Serum is the liquid that separates from the blood when a clot is formed. Kendall/HUnt

Chapter 10 Parts of Blood Kendall/HUnt

Unknown Stain at a Scene Chapter 10 Unknown Stain at a Scene Questions to be answered: Is it blood? Is it human blood? Whose is it? Determine blood type, alcohol content, drugs present Determine the method(s) in which blood may have been deposited Kendall/HUnt

Presumptive Tests for Blood Determination Chapter 10 Presumptive Tests for Blood Determination Kastle-Meyer color test—a mixture of phenolphthalein and hydrogen peroxide; the hemoglobin will cause the formation of a deep pink color if blood is present Hematest® tablet—reacts with the heme group in blood causing a blue-green color Luminol test—reaction with blood to produce light Kendall/HUnt

Chapter 10 Testing for Blood Both the Kastle Meyer and Luminol test for presence of blood are examples of chemical reactions. Kendall/HUnt

Chapter 10 Kendall/HUnt

Human vs Animal Blood Microscopic observation Chapter 10 Human vs Animal Blood Microscopic observation Precipitin test—blood is injected into a rabbit; antibodies are formed; the rabbit’s blood is extracted as an antiserum; the antiserum is placed on sample blood. The sample will react with human proteins, if human blood is present. This test is very sensitive and requires only a small amount of blood. Kendall/HUnt

Animal Blood Larger nucleic red blood cells Frog Blood Chapter 10 Kendall/HUnt

Human Blood Red blood cells are most numerous; 5 to 6 million per mm3 Chapter 10 Human Blood Red blood cells are most numerous; 5 to 6 million per mm3 White blood cells are larger and less numerous; 5 to 10,000 per mm3 Platelets are tiny, cellular fragments; 350 to 500,00 per mm3 Kendall/HUnt

Chapter 10 Secretors 80% of the population are secretors. Their blood-type antigens are found in high concentration in their body fluids such as saliva, semen, vaginal secretions and gastric juice. Kendall/HUnt

Historical Perspective of Blood Typing Chapter 10 Historical Perspective of Blood Typing Karl Landsteiner 1900 4 types In 1940 Rh factor 85% of Caucasions 94% Black Americans 99% Asians Around 1900, Karl Landsteiner discovered that there are four different types of human blood based on the presence or absence of specific antigens found on the surface of the red blood cells. In 1940, Landsteiner and Weiner reported the discovery of the Rh factor by studying the blood of the Rhesus monkey. 85% of Caucasians, 94% of Black Americans and 99% of all Asians are Rh positive. Kendall/HUnt

How is our blood type determined? Chapter 10 How is our blood type determined? Your blood type is established before you are BORN, by specific GENES inherited from your parents. You receive one gene from your MOTHER and one from your FATHER. These two genes determine your blood type by causing proteins called AGGLUTINOGENS to exist on the surface of all of your red blood cells. Kendall/HUnt

Chapter 10 Kendall/HUnt

Chapter 10 Blood Typing A-B-O and Rh systems are the most important in identifying blood An individual that is type A has A antigens on his/her red blood cells Type B has B antigens Type AB has both A and B antigens Type O has neither A nor B antigens Kendall/HUnt

Chapter 10 Agglutination For every antigen there is a specific antibody that will react with it to form clumps (agglutination) For example, Red blood cells containing B antigens will react in the presence of B antibodies Kendall/HUnt

Chapter 10 Kendall/HUnt

Chapter 10 What are blood types? 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 http://www.lanecountyblood.org/images/other/bloodfacts.jpg 45% 40% 11% 4% How common are the 4 blood types? http://learn.genetics.utah.edu/units/basics/blood/types.cfm Kendall/HUnt

Blood Groups Type Antigen Antibody A A B A, AB O, A B, AB O , B B B A Chapter 10 Blood Groups Can Give Blood To Can Get Blood From Type Antigen Antibody A A B A, AB O, A B, AB O , B B B A Neither A nor B AB A and B AB A, B, O, AB Neither A nor B O A and B A, B, O, AB O Kendall/HUnt

Rh Factors A+ A- B+ B- AB+ AB- O+ O- Chapter 10 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 Kendall/HUnt

Rh factor Determined by presence of another antigen Chapter 10 Rh factor Determined by presence of another antigen People having antigen are Rh + People not having are Rh- Kendall/HUnt

Use the results shown to determine the blood type for each sample. Chapter 10 Blood Typing Use the results shown to determine the blood type for each sample. - = No Clumps + = Clump A B Rh Blood Type: ___ To determine a person’s blood type, we add three different serums to blood samples and see if clumps form. Clumps = Positive (+) No Clumps = Negative (-) What would the blood type be for this sample? Kendall/HUnt

- = absent + = present Blood Typing Chapter 10 A B Rh Blood Type: ___ A B Rh Blood Type: ___ Blood Typing Use the results shown to determine the blood type for each sample. A B Rh Blood Type: ___ A B Rh Blood Type: ___ A B Rh Blood Type: ___ - = absent + = present Kendall/HUnt