2. BLOOD GROUPS

3. FACTS ABOUT BLOOD GROUPS THE MOST IMPORTANT BLOOD GROUP IN THE U.S. IS THE ABO GROUP 3 ALLELES FOR THIS GROUP: A,B & O A PERSON CAN ONLY INHERIT 2 ALLELES (GENES) FOR THIS

4. POSSIBLE GENE COMBINATIONS GENOTYPE PHENOTYPE (alleles) (actual blood type) AA AO BB BO AB OO A A B B AB O

5. Antigen In immunology, an antigen is a substance that evokes the production of one or more antibodies. Each antibody binds to a specific antigen by way of an interaction similar to the fit between a lock and a key

6. Antibody An antibody (Ab), also known as an immunoglobulin (Ig), is a large Y-shaped protein produced by B-cells that is used by the immune system to identify and neutralize foreign objects such as bacteria and viruses So the foreign antigen is the “bad guy” and the antibody is the molecule your body uses to fight the foreign antigen

9. Serology – the study of antigen – antibody reactions

10. Laboratory Examination - Individualization The surface of a RBC contains antigens Antigen (Ag) – a glycoprotein that stimulates the body to produce antibodies (Ab) against it Antigens impart blood- type characteristics to the RBC

11. Laboratory Examination – ABO and Rh system

12. Meaning they have the following blood type

14. Rh Factor

15. Red blood cell compatibility table[58][59] Recipien t [1] Donor [1] O−O+A−A+B−B+AB−AB+ O−Y O+YY A−YY A+YYYY B−YY B+YYYY AB−YYYY AB+YYYYYYYY

16. Laboratory Examination – ABO and Rh system Rh factor or D antigen – people having the D antigen are Rh positive; those without are Rh negative Antibodies (Ab) are proteins found in the serum that destroy or inactivate a specific Ag

17. Laboratory Examination – ABO and Rh system The fundamental principle of blood typing is that for every antigen, there exists a specific antibody.

18. Laboratory Examination – ABO and Rh system An Ab will react only with its specific antigen Ab are normally bivalent – having 2 reactive sites Each Ab can simultaneously be attached to antigens on 2 different RBC This creates a network of cross-linked cells seen as clumping or agglutination

19. Laboratory Examination – ABO and Rh system Serology is the study of Ag-Ab reactions

20. Laboratory Examination – ABO and Rh system The population distribution of blood types varies with location and race throughout the world In the US, a typical distribution:

21. Video

22. Laboratory Examination - Individualization In whole blood, RBCs can by typed directly, but in dried stains, indirect methods must be used because there are no intact RBC remaining in the sample

23. Laboratory Examination - Individualization In addition to the A and B Ag, other substances (enzymes) found in the RBC were used to individualize bloodstains Enzymes are proteins that function in regulating many of the body’s chemical reactions Forensic serologists were interested in enzymes that exist in different forms = polymorphic and iso-enzymes This technology led to greater ability to discriminate between individuals and evidentiary material

24. Blood as Evidence General Precautionary Measures Consider all blood and body fluids infectious, whether wet or dry Handle all needles, syringes, blades, and knives with caution; place in puncture- resistant containers Wash hands with soap and water after each assignment or when contaminated Keep all wounds carefully bandaged

25. WHAT DOES THIS TELL YOU ABOUT THE WAY THESE GENES ARE INHERITED? A & B ARE CODOMINANT A & B ARE BOTH DOMINANT OVER O

26. FREQUENCY OF BLOOD TYPES A B AB O 45% MOST COMMON 41 % 10 % 4 % LEAST COMMON

27. UNIVERSAL DONOR: THE BLOOD TYPE THAT CAN BE GIVEN TO ALL OTHER BLOOD TYPES. TYPE O- IS THE UNIVERSAL DONOR. UNIVERSAL ACCEPTOR: THE BLOOD TYPE THAT CAN RECEIVE ALL OTHER BLOOD TYPES. TYPE AB+ IS THE UNIVERSAL ACCEPTOR.

28. Rh FACTOR THE Rh FACTOR IS ANOTHER ANTIGEN (PROTEIN) THAT CAN BE FOUND ON THE SURFACE OF SOME RBC’S PEOPLE WITH THIS PROTEIN ON THEIR RBC’S ARE Rh+. PEOPLE WHO LACK THIS PROTEIN ARE Rh-.

29. ERYTHROBLASTOSIS FETALIS A HEMOLYTIC DISEASE OF NEWBORNS. THE RESULT OF Rh INCOMPATIBILITY THE MOTHER IS Rh- & THE FATHER IS Rh+ BOTH HEMOLYSIS & AGGLUTINATION WILL RESULT

30. NORMAL RBC IMMATURE RBC (NUCLEATED) BROKEN RBC

31. WHAT DISEASE CONDITIONS WOULD YOU EXPECT THIS BABY TO HAVE AT BIRTH? ANEMIA JAUNDICE

33. WHAT IS THE Tx FOR THESE BABIES? A COMPLETE BLOOD TRANSFUSION

34. RHOGAM: CONTAINS ANTI-Rh ANTIBODIES HOW IS IT ADMINISTERED? INJECTION WHEN IS IT ADMINISTERED? DURING THE PREGNANCY & WITHIN 72 HOURS AFTER DELIVERY. PREVENTION?