Blood Types

Genetics of Blood Types

• Your blood type is established before you are BORN, by specific GENES inherited from your parents.

• These two genes - one gene from your MOTHER and one from your FATHER -determine your blood type by causing proteins called AGGLUTINOGENS to exist on the surface of all of your red blood cells.

Serology-study of biological fluids in specific antigen-antibody reactions

• 1901-Karl Landsteiner-ABO blood type system• Blood types based on presence of agglutinogens

(agglutinating antigens) on red blood cells (erythrocytes)

Blood Types

• A – A antigens• B – B antigens• AB – A & B antigens• O no antigens

• Proteins that stimulate production of antibodies• On surface of erythrocytes• Types- A and B• Antibodies-produced against antigens not present• Ex. Type A blood has A antigens, but B antibodies

Antigens (agglutinogens)

What are blood types?

http://learn.genetics.utah.edu/units/basics/blood/types.cfm

There are 3 alleles or genes for blood type: A, B, & O. Since we have 2 genes, there are 6 possible combinations.

Blood Types

AA or AO = Type ABB or BO = Type B

OO = Type OAB = Type AB

Blood Types

Blood Type

Antigen Antibodies in plasma

Can give to

Can receive from

A A Anti B A,AB O, A

B B Anti A B,AB O.B

AB AB No A or B AB O,A,B,AB

O Neither A nor B

A and B O,A,B,AB

O

• Proteins that stimulate production of antibodies• On surface of erythrocytes• Types- A and B• Antibodies-produced against antigens not present• Ex. Type A blood has A antigens, but B antibodies

Antigens (agglutinogens)

Rh Factor

• Rh + has the antigen• Rh – does not have the antigen

Rh Factors• Scientists sometimes study Rhesus monkeys

to learn more about the human anatomy because there are certain similarities between the two species. 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-).

A+ A-B+ B-

AB+ AB-O+ O-

http://www.fi.edu/biosci/blood/rh.html

Rh antigen is also importantPeople either have the antigen or do not

Rh-negative people will develop antibodies tothe Rh antigen if they are exposed to theRh-positive blood

If a Rh-negative woman becomes pregnantwith a Rh-positive fetus she may makeantibodies to the fetus’ RBCs

This can be prevented with RhoGAM

Frequency of Blood Types in US

How common is your blood type?

Blood types are inheritedIn some parts of the world some blood types are

more common than others

In U.S.:~45% are O, ~40% are A, 12% are B, andabout 3% are AB

about 85% are Rh-positive

Blood TransfusionsA blood transfusion is a procedure in which blood is given to a patient through an intravenous (IV) line in one of the blood vessels. Blood transfusions are done to replace blood lost during surgery or a serious injury. A transfusion also may be done if a person’s body can't make blood properly because of an illness.

Who can give you blood?

People with TYPE O blood are called Universal Donors, because they can give blood to any blood type.

People with TYPE AB blood are called Universal Recipients, because they can receive any blood type.

Rh + Can receive + or - Rh - Can only receive -

Universal Donor

Universal Recipient

Blood Transfusion

• In the United States, a blood transfusion is needed about every two seconds.

Did You Know?

When a person donates a pint of blood; that blood is separated into red blood, plasma and platelets.

Each of those can be given to 3 different patients.

Transfusions are preferred between people ofthe same blood type

If blood is properly processed and administered:

A can receive from A and OB from B and OAB from AB, A, B and OO only from type O- but can donate to everyone

else

Rh-positive can receive from negative andå positiveRh-negative only from negative

Microscopic Views

Bird Blood

Cat Blood

Dog Blood

Fish Blood

Frog Blood

Snake BloodHuman Blood

Horse Blood

Facts

• 700 RBC to 1 WBC• CO combines 210 times faster to RBC than

CO2• Most of your blood is located in your veins,

64%• Veins appear blue because the blood is a dark

reddish (bluish) color.

When Things Go Wrong

• Anemia• Leukopenia – low WBC count• Myeloma – B lymphocytes cancer• Leukemia – blood cancer excess count• Mononucleosis – atypical WBC, Virus• AIDS