Blood Types & Inheritance

Dr. Charles Drew Today's American Red Cross blood program is the result of the efforts of Dr. Charles R. Drew, a blood specialist, surgeon, educator and scientist. His pioneering work in blood collection, plasma processing and transfusion laid the foundation for modern blood banking.

What are antigens & antibodies? The differences in human blood are due to protein molecules called antigens and antibodies. The antigens are located on the surface of the red blood cells’ plasma membrane. The antibodies are in the blood plasma (liquid). Antibodies are used to identify/destroy foreign blood cells.                         

What are the different blood groups? Individuals have different types and combinations of antigens and antibodies.

What happens when different blood types are mixed? Not all blood groups are compatible with each other. Mixing incompatible blood groups leads to blood clumping or agglutination, which is dangerous for individuals. This can lead to death

How is blood type genetically determined? The ABO genes are determined by multiple and co-dominant alleles. There are three different alleles for human blood type: IA ,IB , & I Since there are 3 different alleles, there are 6 different possible genotypes and 4 different possible phenotypes.

A & B antigens are present Neither A nor B antigens are present OO Phenotype/Blood Type Genotype Meaning O Aa or AO BB or BO AB A & B antigens are present Neither A nor B antigens are present OO Only the A antigen is present A Only the B antigen is present B AB

A & B antigens are present Neither A nor B antigens are present ii Phenotype/Blood Type Genotype Meaning O IAi or IA IA A & B antigens are present Neither A nor B antigens are present ii Only the A antigen is present A Only the B antigen is present IBi or IB IB B AB IAIB

Blood Transfusions - who can receive blood from whom? The transfusion will only work if the recipient does not produce antibodies for the donor’s blood type.

Blood Types Can donate blood to Can receive blood from AB AB, A, B, O A A & AB A & O B B & AB B & O O

The Universal Donor can donate blood to a person any blood type. Which blood type is the Universal Donor? O- The Universal Recipient can receive blood from any blood type. Which blood type is the Universal Recipient? AB+

Population Distribution of Blood Types in the U.S. Chapter 10 Population Distribution of Blood Types in the U.S. Type Percent O 45 A 40 B 11 AB 4 Kendall/HUnt

Practice Problems!

Give the genotype & phenotype ratios for the following crosses: IAIA x IBi Genotypes: 1 IAIB : 1 IAi Phenotypes: 1 AB : 1 A Type O x Type AB Genotypes: 1 IAi : 1 IBi Phenotypes: 1 A : 1 B

Who’s Baby is it? At the hospital, 2 newborn babies were accidentally mixed up and the parents questioned which baby belonged to whom. The blood groups of everyone involved are listed below. Determine which baby belongs to which couple. Baby 1 – Type A Mr. Brown – Type AB Baby 2 – Type O Mrs. Brown – Type B Mr. Smith – Type B Mrs. Smith – Type B

Who’s baby is it? answer… Baby 1 has to belong to Mr. & Mrs. Brown. There is no way that they could create a Type O (ii) baby when only one parent could possibly contain the i allele. Baby 2 has to belong to Mr. & Mrs. Smith. There is no way that they could create a Type A (IA IA, IAi) baby with out either carrying the IA allele.

Which child is adopted? The Tyler family has three kids, one of which is adopted. The blood types of the parents and children are listed below. Determine which child is adopted. Mom -Type AB John- Type B Dad- Type O Martha- Type AB Zackary- Type A

Which child is adopted? ANSWER Martha (IAIB) is adopted because Dad is Type O (ii) and could not have given either of her two alleles.

Genetics and Biotechnology TEST Study Guide Be familiar with the following terms, homozygous, heterozygous, phenotype, genotype, pure bred, and hybrid. Know how to solve genetics problems. Know the purpose of a test cross.

Be familiar with the following terms: selective breeding, genetic engineering, cloning, DNA fingerprinting. Know how to read a karyotype. Be able to do sex linkage problems and blood group problem Know how to read a pedigree(we will do this when I return)