Name _____________________________Date _______________ Period ________
ABO Multiple Allele Worksheet
Directions: fill in the chart and answer the questions.
Phenotypes
Antigens on RBC
Antibodies in plasma
Genotypes
A+
BAB+
O1. What is the expected genotypic ratio among children born to a mother having the genotype IAi and a
father with the phenotype AB?
2. One parent has the blood type A and the other blood type B. What are the genotypes of the parents if
they produce children with only blood type AB?
3. One parent has the blood type A and the other blood type B. What are the genotypes of the parents if
1/2 the offspring are AB and the other 1/2 A?
4. One parent has the blood type A and the other blood type B. What are the genotypes of the parents
if the offspring produce the following blood types...1/4 AB, 1/4 A, 1/4 B, and 1/4 O?
5. From the following blood types, determine which baby belongs to which parents.
Baby 1 belongs to the _____________ Family
Mrs. Doe.............Type A
Mr. Doe .............Type A
Baby 2 belongs to the ___________ Family
Mrs. Jones ......... Type A
Mr. Jones .......... Type AB
Baby 1 ............. Type O
Baby 2 ............. Type B
6. In a particular family, one parent has Type A blood, the other has Type B. They have four children.
One has Type A, one has Type B, one has Type AB, and the last has Type O. What are the genotypes
of all six people in this family?
7. Another woman has the same problem. Her blood type is A, her child’s is B. She again has three
candidates for fatherhood. Their blood types are: Man #1, B; Man #2, AB; Man #3, O. Based on
blood types, the mother says it must have been #1.
a. Do you agree? Why or why not?
8. Describe why an Rh positive man could have multiple transfusions of negative blood.
9. Describe why a negative woman could only have one transfusion of positive blood.
10. A male baby dies of hemolytic disease, describe as much as you can about the phenotypes and
genotypes of his parents, siblings and the baby too.
11. If a sickle cell trait woman marries a normal man what can you say about their children’s ability to
survive a malaria attack.
12. A man with AB blood is married to a woman with AB blood. What blood types will their children be
and in what proportion?
13. A man who has type B blood (genotype: homozygous) is married to a woman with type O blood. What
blood type will their children have?
14. A woman with type A blood (genotype: heterozygous) is married to a type B person (genotype:
heterozygous). What blood types will their children have?
15. A woman with type A blood is claiming that a man with type AB blood is the father of her child, who is
also type AB. Could this man be the father? Show the possible crosses; remember the woman can have IAi
or IAIA genotypes.
16. A man with type AB blood is married to a woman with type O blood. They have two natural children,
and one adopted child. The children's blood types are: A, B, and O. Which child was adopted?
17. A person with type O blood is married to a person with type A blood (unknown genotype). They have 6
children, 3 of them have type A blood, three of them have type O blood. What is the genotype of the two
parents?
18 Determine the blood types and fill in the chart:
Name
Anti a
Anti b
Anti Rh
added
added
added
Mr A
Clump
No clump
Clump
Mr B
Clump
Clump
No clump
Ms C
No clump
Clump
No clump
Dr D
No clump
No clump
Clump
Blood type
Possible Genotypes