Thalassemia is an inherited blood disorder that results in abnormal hemoglobin formation and excessive red blood cell destruction, leading to anemia. There are two main types: alpha thalassemia affects genes on chromosome 16 and causes excess beta globin, while beta thalassemia affects the gene on chromosome 11 and causes excess alpha globin. Symptoms include fatigue, growth issues, breathing problems, and enlarged spleen. Treatment involves regular blood transfusions to address anemia, along with chelation therapy to remove excess iron that can damage organs. For severe cases, a bone marrow transplant may potentially cure the condition.

2. o Thalassemia is an inherited blood disorder that can
result an abnormal formation of hemoglobin .The
disorder results in excessive destruction of red blood
cells which leads to anemia .
o There are two main types of thalassemia disorders:
• α – alpha thalassemia
• β - beta thalassemia.

3. It is most common
among people of Italian,
Greek, Middle Eastern ,
South Asian , and African
descent, Males and
females have similar rates
of disease.

4. α - alpha thalassemia

5. oα -thalassemia occurs when the related genes to the α - globin
protein are missing or changed (mutated), resulting excess of β-globin
within RBCs.
oα -globin is coded on two consecutive genes on Chromosome 16 :
• HBA1 ( hemoglobin alpha 1)
• HBA2 (hemoglobin alpha 2)

6. α – Thalassemia classification :
4 possible mutation states:
• Loss of ONE allele :
silent carrier → asymptomatic
• Loss of TWO alleles :
thalassemia minor (trait) → mild anemia
• Loss of THREE alleles :
HbH disease → hemolytic anemia—
anemia caused by the rapid breakdown
of the RBCs .
• Loss of FOUR alleles :
α – Thalassemia major → Hydrops fetalis
, anemia begins before birth so in this
state fetal doesn’t survive .

8. If both parents carry alpha thalassemia minor in which the two
abnormal genes of each parent are on opposite chromosomes,
their children will inherit alpha thalassemia minor
α ααα
- - --
αα
- -
Both parents carry
α – Thalassemia
minor
α – Thalassemia minor

9. both parents carry alpha
thalassemia minor with two
abnormal alpha globin genes on
the same chromosome
-α
α -
-α
α -
αα
α α
-α
α -
--
- -
25%
normal
hemoglobin
50%
α – Thal trait
25%
α – Thal major
( hydrops fetalis)

10. one parent has alpha
thalassemia minor with
two abnormal alpha
globin genes on the same
chromosome
and the other parent has the silent
carrier state with a single abnormal
alpha globin gene on one
chromosome
-α
α -
αα
α -
-α
α -
αα
α -
αα
α α
α-
- -
25%
normal
hemoglobin
25%
α – Thal trait
25%
Silent Carrier
25%
HgH disease

11. β- beta thalassemia

12. oβ-thalassemia occurs when the related
genes to the β- globin protein are missing
or changed (mutated), resulting excess of
α-globin within RBCs.
oBeta-globin is coded by a single gene on
Chromosome 11:
•HBB gene

13. β- Thalassemia classification :
• β- Thalassemia Minor (trait):
One gene defect → asymptomatic
• β- Thalassemia Major
( Cooley's thalassemia) :
Two genes defective → sever
decrease in β- globin synthesis,
Severe anemia.

15. When one parent carry
β- Thalassemia Major
and the other carry
β- Thalassemia minor
(carrier ) .
Risk for child to:
• Have β- Thalassemia Major 50%
• Have β- Thalassemia minor
(carrier) 50%

16. When both parents carry
β- Thalassemia Major .
Risk for child to:
• Have β- Thalassemia Major 100%

17. When one parent is
unaffected and the other carry
β- Thalassemia minor (carrier ) .
Risk for child to:
• Have β- Thalassemia Major 0%
• Have β- Thalassemia minor
(carrier) 50%

18. When both parents carry
β- Thalassemia Manor
(trait) .
Risk for child to:
• Have β- Thalassemia Major 25%
• Have β- Thalassemia minor
(carrier) 50%

19. Symptoms
• The most severe form is alpha
thalassemia major causes
stillbirth
• Children born with beta
thalassemia major (Cooley’s
anemia) are normal at birth,
but develop severe anemia
during the first year of life.

20. •Bone deformities: Thalassemia can
make the bone marrow expand, especially in
the face and skull. The expansion makes
bones thin and brittle.
•Fatigue
•Growth failure
•Shortness of breath
•Weakness

21. •Splenomegaly (Enlarged spleen) :The
spleen filters unwanted material, such as old or
damaged blood cells. And since there is a
destruction of a large number of RBCs and the
task of removing these cells causes the spleen to
enlarge.
• Jaundice :Yellow discoloration of skin or
whites of the eyes.

22. Treatment
• Blood transfusion :
people with thalassaemia major or other severe
types will need to have regular blood transfusions
to treat anaemia.
How often you need to have transfusions depends
on the type of thalassaemia you have.
Blood transfusions are safe, but they can cause
Iron overload.

23. • chelation therapy ( removing excess iron):
Iron overload caused by regular blood
transfusions , and it can damage the heart, liver
and spleen .
 The treatment will start once the patient had
around 10 blood transfusions
Medications used in chelation therapy are
known as chelating agents
• splenectomy :
Surgical removal of the spleen for the patients
with the splenomegaly (enlarged spleen)

24. Stem cells or bone marrow transplant :
 they are the only cure for thalassaemia.
Stem cells are produced in bone marrow (the spongy
bone) and have the ability to develop blood cells.
stem cells will be given from a matched donor. These
cells then start to produce healthy RBCs and replace
them with the affected ones.
This treatment carries numbers of risks , such as graft
versus host disease, where the transplanted cells start
to attack the other cells in the body.

25. Prevention
We can’t prevent thalassemia because it’s an
inherited disease . However parental tests can
detect this blood disorder before birth.
Prenatal testing involves taking a sample of
amniotic fluid or tissue from the placenta.
(Amniotic fluid is the fluid in the sac surrounding
a growing embryo. The placenta is the organ that
attaches the umbilical cord to the mother's
womb.) Tests done on the fluid or tissue can
show whether the baby has thalassemia and
how severe it might be.

26. Time for Questions

27. Q1 : when α– Thalassemia and β – thalassemia
occur !?
α -thalassemia occurs when HBA1 and HBA2
genes on chromosome 16 are mutated.
β-thalassemia occurs when HBB gene on
chromosome 11 is mutated .

28. • Fatigue
• Growth failure
• Shortness of breath
• Weakness
• Bone deformities
• Splenomegaly (Enlarged spleen)
•Jaundice
Q2 : list 4 symptoms of thalassemia :

29. Q3 : If there’s one parent with alpha
thalassemia minor (mutated genes are on the
same chromosome) and the other one is a silent
carrier, what are the states there children may
get ?

30. alpha thalassemia minor silent carrier-α
α -
αα
α -
-α
α -
αα
α -
αα
α α
α-
- -
25%
normal
hemoglobin
25%
α – Thal trait
25%
Silent Carrier
25%
HgH disease

31. Q4 : Blood transfusions can cause Iron overload, explain
what Iron overload can cause, and what’s the treatment
for iron overload and when it can be used ?
it can damage the heart, liver and spleen, the
chelation therapy( removing excess iron)
will be the treatment , and it will start once
the patient had around 10 blood transfusions

32. Q5 : why does the spleen get enlarged with
Thalassemia ?!
Because there is a destruction of a large
number of RBCs and the task of removing
these cells causes the spleen to enlarge

33. References :
• Essential hematology A.V Hoffbrand , P.A.H Moss and J.E pettit Fifth edition
• National heart, lung and blood institution
https://www.nhlbi.nih.gov
• United kingdom thalassemia society
http://ukts.org
• Mayo clinic
http://www.mayoclinic.org
• UK National health service
http://www.nhs.uk