Blood Type Genetics In traits with multiple alleles

Blood Type Genetics

In traits with multiple alleles, each individual can carry any two of the several possible alleles. Ex. BLOOD TYPE The gene for blood type has 3 possible alleles.

Blood Group Genes • There is 1 gene for blood type • There are 3 alleles for blood type: A, B, & i (O). • A&B are codominant to i (O). and both

The ABO blood system Genotypes IA I A IA I B IA i IB I B IB i ii Phenotypes (Blood types) A AB A B B O Note: • Blood types A and B have two possible genotypes – homozygous and heterozygous. • Blood types AB and O only have one genotype each. © 2007 Paul Billiet ODWS

How blood types work…. How common are the 4 blood types? 4% 11% 45% 40% http: //www. lanecountyblood. org/images/other/bloodfacts. jpg http: //learn. genetics. utah. edu/units/basics/blood/types. cfm

Practice Problems: 1. A mother is IA IB and a father is ii. Draw the punnett square. IA IB i i What is the probability their offspring will have A type blood? Can they have an offspring with O blood?

Practice Problems: 1. A mother is IA IB and a father is ii. Draw the punnett square. IA IB i IA i IB i What is the probability their offspring will have A type blood? 50% Can they have an offspring with O blood? No

2. A mother is IAi and a father is IB IB Draw the punnett square. What is the probability their offspring will have B type blood? Can they have an offspring with O blood?

Rh Factors • Scientists sometimes study Rhesus monkeys to learn more about the human anatomy. While studying Rhesus monkeys, a certain blood protein was discovered. This protein is also present in the blood of some people. Other people, however, do not have the protein. • The presence of the protein, or lack of it, is referred to as the Rh (for Rhesus) factor. • If your blood does contain the protein, your blood is said to be Rh positive (Rh+). If your blood does not contain the protein, your blood is said to be Rh negative (Rh-). http: //www. fi. edu/biosci/blood/rh. html A+ AB+ BAB+ ABO+ O-