1. Blood Type
Ch. 14 and Section 37.2

2. I. Human Genes and our Blood
A. Blood Group Genes
1. Antigens/antibodies
2. Genes are responsible for human blood groups
a. ABO blood groups
b. Rh blood groups

3. Blood Group Terms
Antigens: chemical structures imparting specific properties to the surface of the RBC
Antibodies: protein substance developed in response to foreign body substances

4. ABO Blood Group is results in 3 phenotypes:. Type A Type B Type O
There are 3 alleles for this gene, IA, IB, and i.
Alleles IA and IB are codominant.
ABO Blood Group is results in 3 phenotypes:.
Type A
Type B
Type O
Co-Dominant
Recessive

5. Blood types: Type A, B, or O?
If your genotype is IAIA, your phenotype is ______________
If your genotype is IBIB, your phenotype is ______________
If your genotype is IAi, your phenotype is ______________
If your genotype is ii, your phenotype is ______________
If your genotype is IAIB, your phenotype is ______________

6. Let’s do a Punnett Square….
Cross a heterozygous type A mom with a recessive dad. Give the possible genotypes and phenotypes of the offspring.
Genotype:
Phenotype:

7. Blood cells have either “A or B” antigens on outside surface of blood cell or NO antigens, which gives you blood type “O”.

8. The Rh Factor
Rh Factor – type of protein on the surface of Red Blood Cells
If the Rh antigen is also present, the person is Rh+, if he/she does not have it, they are Rh-
Rh blood group is determined by a single gene with two alleles
POSITIVE [Rh+, Rh+] or {Rh+, Rh-] (Dominant)
NEGATIVE [Rh-, Rh-] (Recessive)

9. Blood Typing
The presence or absence of 3 specific surface antigens (A, B & Rh) determine your “blood type”
Your surface antigens are recognized by your immune defense system as “self”.
Plasma antibodies are responsible for “protecting” you from an incompatible blood type.
Anti-Rh antibodies are not “automatically” made by Rh- people

10. Blood Typing
Your blood cells have surface antigens based on your blood type
Your plasma makes antibodies against the antigens you don’t have

11. Human Genes The i allele is recessive.
Individuals with alleles IAIA or IAi produce only the A antigen, making them blood type A.
Fig page 344

12. Human Genes
Individuals with alleles IA and IB produce both A and B antigens, making them blood type AB.

13. Human Genes
Individuals who are homozygous for the i allele (ii) produce no antigen and are said to have blood type O.

14. WRONG BLOOD TYPE???
If given the “wrong” blood type for medical purpose, the immune system would recognize the blood cells as foreign and destroy them!

15. Rh Incompatibility
When Rh– person receives Rh+ blood in a transfusion  person develops antibodies against the Rh+ factor
Clinical problem if second transfusion of Rh+ blood given  Rh antibodies will clump with the Rh antigens
S/S of transfusion reaction: chills, fever, rash, itching, SOB, nausea, nephralgia, hematuria, shock & death
S/S = signs and symptons, SOB = shortness of breath, nephralgia = kidney pain, hematuria = blood in urine

16. We say the universal donor is Type ____ and the universal recipient is Type ______.
However, Rh factor does matter!!!