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Blood Type. Ch. 14 and Section 37.2. 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. Blood Group Terms.
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Blood Type Ch. 14 and Section 37.2
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
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
ABO blood group • 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
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 ______________
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:
Blood cells have either “A or B” antigens on outside surface of blood cell or NO antigens, which gives you blood type “O”.
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)
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
Blood Typing • Your blood cells have surface antigens based on your blood type • Your plasma makes antibodiesagainst the antigens you don’t have
Human Genes • The i allele is recessive. • Individuals with alleles IAIA or IAi produce only the A antigen, making them blood type A. Fig. 14-4 page 344
Human Genes • Individuals with alleles IA and IB produce both A and B antigens, making them blood type AB.
Human Genes • Individuals who are homozygous for the i allele (ii) produce no antigen and are said to have blood type O.
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!
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
We say the universal donor is Type ____ and the universal recipientis Type ______. • However, Rh factor does matter!!!