Lesson 8:
Presented by:
INTENDED LEARNING OUTCOMES
At the end of this lesson, you will be able to:
1. Illustrate how blood types are inherited;
2. Explain the determination and inheritance of the ABO
blood types; and
3. Publish a persuasive essay online regarding the
significance of blood types.
Genetics of Human Blood Type
•The blood type is the human trait that has been of much use in the
study of medicine and of human population genetics.
Karl Landsteiner – first discovered the blood groups
in the 1900.
• The ABO blood group is identified based on the
presence or absence of one or both of the two
different antigens A and B.
• Antigens - are substances that stimulate the
production of antibody.
Genetics of Human Blood Type
•The following are the different human blood types under the ABO
group:
Type A - carries the antigen A.
Type B - carries the antigen B.
Type AB - carries both A and B.
antigen.
Type O - does not carry either of
the antigen.
Genetics of Human Blood Type
•The following table summarizes how the blood types can be matched
for transfusion:
Table 2. Blood Donor for Specific Type
Genetics of Human Blood Type
• Rh factor which could also be either present or absent from the
blood. Blood with the Rh factor is considered positive (+) while its
absence makes the blood negative (-).
Genetics of Human Blood Type
Figure 13. Compatibility of Blood Types
Genetics of Human Blood Type
• Agglutination – an allergic reaction when incompatible blood
types are mixed together, the antibodies bound to the surface
markers of the cells that make them lump together.
• It can cause a notable shock and eventual death of the recipient of
the blood.
Genetics of Human Blood Type
Like all other genetic traits, blood type is inherited from parents. The
table that follows summarizes the possible blood types of children
resulting from different crosses.
Genetics of Human Blood Type
•Determining the Rh blood type is also crucial for pregnant women.
Rh-sensitization
Rh (Mother)
Rh +
2)
(Baby 1)
Genetics of Human Blood Type
Some questions you may ask:
• What type of blood is in greatest demand?
- Types O negative and O positive
Genetics of Human Blood Type
Some questions you may ask:
• What is the type of blood most difficult to obtain?
- AB negative
Genetics of Human Blood Type
Some questions you may ask:
• What are the types of people who are potential donors?
- To donate blood, you must be in good general health,
weigh at least 110 pounds, and be at least 16 years old. Parental
consent is required for blood donation by 16 year olds.
• Basic requirement of a potential blood donor:
Weight: At least 110 lbs (50 kg).
Blood volume collected will depend mainly on you body weight.
Pulse rate: Between 60 and 100 beats/minute with regular rhythm.
Blood pressure: Between 90 and 160 systolic and 60 and 100 diastolic.
Hemoglobin: At least 125 g/L.
Genetics of Human Blood Type
Some questions you may ask:
• How blood is tested or screened for disease?
- After blood is drawn, it is tested for ABO group (blood type) and
RH type (positive or negative). Test for unexpected red blood cell antibodies
that may cause problems for the recipient can be performed upon the
request of the patient's attending physician. Screening tests performed are
listed below:
• Hepatitis B surface antigen (HBsAg)
• Hepatitis C virus antibody (anti-HCV)/ antigen (HCV Ag)
• HIV-1 and HIV-2 antibody (anti-HIV-1 and anti-HIV-2) antigen (HIV-1 and HIV-2 Ag)
• Serologic test for syphilis
• Nucleic acid amplification testing (NAT) for HIV-1, HCV and HBV if available
Type O is considered as the Universal
Donor while type AB is the Universal
Recipient. Why is this so?
THANK YOU FOR
LISTENING