Blood Type Testing Lab Report
Section 1101
Nattanit Trakullapphan (Nam)
Chawalnrath Wongdeshanan (Kat)
Introduction:
figure 1.1
(Blood type n.d.)
figure 1.2
(Blood type, Antigens-Antibodies n.d.)
Multiple Alleic Traits are called when there is more than two possible alleles. One
example of multi alleic traits is ABO blood type in human population.[6] There are three alleles
for blood type, which are IA, IB and i. IA and IB are dominant to allele i. And these three possible
alleles can produce four blood type in human population. IAIA and IAi make blood type A; IBIB
and IBi make blood type B while only IAIB makes blood type AB and only ii makes blood type O.
Both blood type A and B can be either heterozygous or homozygous, but blood type AB can be
only heterozygous and blood type O can be only homozygous. Genotype IAIB of blood type AB
is co-dominant because both dominant alleles, A and B, fully express their characteristic.
The red blood cells of an individual contain antigens on their surfaces that matching to
their blood group and antibodies in blood plasma that identify and combine with the antigen sites
on the surfaces of red cells of another type. Antigens and antibodies are certain protein molecules
presence in red blood cells.[4] Antibodies are located in the blood plasma while antigens are in
the surface of red blood cells. Antibody also can be called immunoglobulin.[1] It is a protective
protein in our immune system against the foreign antigens that come in our body.
Each blood type is named by its antigen in red blood cells. For example, as in figure 1.1,
blood type A contains A antigens, blood type B contains B antigens, blood type AB contains
both, and blood type O contains neither. This means that blood type A contains B antibodies,
blood type B contains A antibodies, blood type O contains neither, and blood type O contains
both as in figure 1.2. It is because A antibodies reacts with its corresponding antigen, which is A,
and B antibodies reacts with B antigens. The reaction between red cells and corresponding
antibodies usually results in clumping or agglutinating of the red cells.[3]
To do blood type testing, in this experiment, we can use agglutination tests, which is a
method to check for certain antigens or antibodies.[5] This method can show whether an
individual has which blood type. Agglutination of red cells results from antibody cross-linkages
established when different specific combining sites of one antibody react with antigen on two
different red cells.[2] This means that if anti-A antibodies react with A antigens, anti-B antibodies
react with B antigens, and anti-AB antibodies react with both A and B antigens, blood clot will
be formed. If testing with blood type O, nothing will change because blood type O does not
contain any antigen.
Therefore, the purpose of this experiment is to check how antigens and antibodies interact
and to know the individual blood type and know the possibilities of the blood type of the baby
from blood type of parents. It is important to do this experiment and know our blood type
because if we know our blood type, we will know which blood types do not match with us. If
they do not match, they can cause us to death. Since the agglutinated red cells can block blood
vessels and inhibit the circulation of the blood to various parts of the body.[4] Also, the
agglutinated blood cells crack and its contents leak out in the body, which when hemoglobin gets
outside the red blood cells, if becomes toxic, leading to death.
Materials:
● 2 Microscope Slides
● Anti-A, Anti-B and Anti-AB
● Markers
● Lancets
● Lancet Device
● Ethanol
● Cotton Ball
● 3 Toothpick
Method:
figure 2
1. Draw 2 one-diameter circles on each slide and mark them as shown in figure 2.
2. Mark each circle control, Anti-A, Anti-B and Anti-AB as in figure 2.
Slides
A Control B AB
A circle with 1 cm diameter
3. Puncture the tip of your finger.
4. Drop one drop of blood in each slide.
5. Drop one drop of anti-A antibody in circle A, of anti-B antibody in circle B and of anti-
AB antibody in circle AB. (Do not drop any in the control)
6. Mix the blood and antigen with different toothpick thoroughly.
7. Wait 10 seconds and observe the blood in each slide.
Results:
Data Table 1: Blood Coagulation
State: Coagulation or No-coagulation
Control None
Anti-A Coagulation
Anti-B No-coagulation
Anti-AB Coagulation
Figure 3. The results
from the data table
and the picture shows
there is a blood
coagulation or blood
clot when mixing
with anti-A
antibodies and anti-
AB antibodies while
there is no change in
control and anti-B
antibodies.
Discussion:
From the results, when the blood mixed with anti-A antibodies and anti-AB antibodies,
blood agglutination was formed, meaning that in the blood there was A antigen which belongs to
blood type A. We could say that this blood was blood type A because although it reacted with
anti-AB antibodies, it did not show any reaction in anti-B antibodies, which always reacts with B
antigen. And if it were blood type B, the blood would not be agglutinated when mixing with anti-
A antibodies. Thus, in the blood, there was only A antigen that could identify it was a blood type
A. Also, it could not be blood type O because there would be no changes in all circles—no blood
coagulation—if it were blood type O. In addition, there had to be blood coagulation in two
circles, A and AB, if the blood was A blood type since in the anti-AB antibodies, anti-A
antibodies were also present, so it formed an interaction which was blood agglutination. From
knowing this, it would be dangerous if blood type A were injected to a person with blood type B
or if injected blood type A or B to a person with blood type O.
Nam’s Scenarios (Nam’s blood type is A, and Nam’s parents have blood type of A and B)
1. If mother has genotype IAIA and father has genotype IBIB:
IA IA
IB IAIB IAIB
IB IAIB IAIB
A baby will 100% have blood type AB.
2. If mother has genotype IAi and father has genotype IBIB:
IA i
IB IAIB IBi
IB IAIB IBi
A baby will have 50-50 chances to have blood type AB or B.
3. If mother has genotype IAIA and father has genotype IBi:
IA IA
IB IAIB IAIB
i IAi IAi
A baby will have 50-50 chances to have blood type AB or A.
4. If mother has genotype IAi and father has genotype IBi:
IA i
IB IAIB IBi
i IAi ii
A baby will have 25% chance to have blood type AB, B, A or O.
=> If Nam has blood type A, the possible genotypes of mother are IAIA with IBi of father, or IAi
with IBi of father.
Kat’s Scenarios (Kat’s parents both have blood type of O)
If mother has ii blood type and father has ii blood type, too:
i i
i ii ii
i ii ii
The baby will have 100% blood type O, meaning that Kat has blood type O.
Conclusion:
In this experiment, we did blood type testing with considering how the blood would
change when it was mixed with each antibodies: anti-A, anti-B, anti-AB. And we indicated from
the changing what blood type it was. For the changing, it happened because of antibody cross-
linkages established when one antibody reacts with antigen on two different red cells. Antibodies
binded with its corresponding antigens to destroy them as when B-type blood is injected into the
one with blood type of A. The anti-B antibodies present in blood type A will interact with
antigen B from blood type B, forming blood clot. That blood clot can bring an individual to
death because when the substances get out from the cracking of agglutinated red blood cells, they
turn toxic. Hence, it is very necessary to know our blood type and which blood type can match
with ours. A person with blood type AB can accept all blood types. A person with blood type A
can receive blood from.
References
[1] Britannica. (2014). Antibody [Online]. Available:
http://www.britannica.com/EBchecked/topic/27783/antibody [Saturday. 14-March-2015
18:39]
[2] Britannica. (2014). Agglutination Tests [Online]. Available:
http://www.britannica.com/EBchecked/topic/9064/agglutination-test [Sunday. 15-March-
2015 19:12]
[3] Britannica. (2014). Blood Group [Online]. Available:
http://www.britannica.com/EBchecked/topic/69795/blood-group/256882/The-importance-
of-antigens-and-antibodies [Saturday. 14-March-2015 18:46]
[4] Nobelprize. (2015). Blood Groups, Blood Typing and Blood Transfusions [Online]. Available:
http://www.nobelprize.org/educational/medicine/landsteiner/readmore.html [Saturday. 14-
March-2015 18:43]
[5] Vorvick, L. (2013). Latex agglutination tests [Online]. Available:
http://www.nlm.nih.gov/medlineplus/ency/article/003334.htm [Sunday. 15-March-2015
19:28]
[6] Wang, Y. (nd). Multiple Alleles, Epistasis, and Pleiotropy [Online]. Available:
http://www.bio.miami.edu/dywang/MultipleAlleles-MultifactorialTraits___.html
[Saturday. 14-March-2015 18:22]
Blood type, Antigens-Antibodies, n.d. photograph, viewed 14 March 2015,
<http://i284.photobucket.com/albums/ll14/polyvoreaddict/Untitled-1.png>.
Blood type, n.d. photograph, viewed 14 March 2015, < http://fblt.cz/wp-
content/uploads/2013/12/krevni-skuiny-ENG-01.jpg>.
