Beta Thalassemia by Sylvester

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Beta Thalassemiaby Sylvester

• Definition Thalassemia is inherited disorders
  characterized reduced or absent amounts of
  hemoglobin, the oxygen-carrying protein inside
  the red blood cells.

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Two Basic Groups of Thalassemia Disorder

• Alpha Thalassemia
• Beta Thalassemia A person with this disorder
  has two mutated genes

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There are 3 types of Beta Thalassemia

• Thalassemia Minor
• Thalassemia Intermediate.
• Thalassemia Major or Cooley's Anemia

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Thalassemias
In the case of beta thalassemias, in contrast
to alpha -thalassemias, the most frequently
encountered molecular abnormalities are point
mutations and short insertions or deletions
limited to a few nucleotides
chain synthesized
chain is still synthesized. The quantity of
globin chain, which is made, varies largely from
one molecular defect to another, this chain may
be structurally normal or abnormal In beta 0
thalassemias , the gene is unable to encode for
any functional mRNA and therefore there is no
beta chain synthesize
Two situations have clearly to be distinguished
In beta thalassemias, the mutated gene
encodes for a small amount of normal mRNA and,
thus, a low amount of
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Beta Thalasemia

• It is caused by a change in the gene for the beta
  globin component of hemoglobin
• It can cause variable anemia that can range from
  moderate to severe.
• Beta thalassemia trait is seen most commonly in
  people with the following ancestry Mediterranean
  (including North African, and particularly
  Italian and Greek), Middle Eastern, Indian,
  African, Chinese, and Southeast Asian (including
  Vietnamese, Laotian, Thai, Singaporean, Filipino,
  Cambodian, Malaysian, Burmese, and Indonesian

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Symptoms of Beta Thalassemia

• It is characterize by severe anemia that can
  begin months after birth
• Paleness
• Delays in growth and development
• Bone marrow expansion.
• Untreated Beta Thalassemia major can lead to
  child death due to heart failure.

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Alpha and Beta Thalassemias

• The thalassemias are, therefore, considered
  quantitative hemoglobin diseases.
• Because all types of thalassemia are caused by
  changes in either the alpha- or beta-globin gene.
  These changes cause little or no globin to be
  produced.

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Treatment of Beta Thalassemia

• Regular blood transfusion helps prevent severe
  anemia and allows for more normal growth and
  development
• There are various medications that target the
  production of red blood cells (i.e.
  erythropoeitin)

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References

• First Known Heart Attack Associated With Beta-
  thalassemia Major Reported." Heart Disease Weekly
  February 22, 2004 10.
• Bowden, Vicky R., Susan B. Dickey, and Cindy
  Smith Greenberg. Children and Their Families The
  continuum of care . Philadelphia W.B. Saunders
  Company, 1998.
• "Thalassemias." In Principles and Practice of
  Medical Genetics , Volume 2, edited by Alan E.H.
  Emery, MD, PhD, and David L. Rimoin, MD, PhD. New
  York Churchill Livingstone, 1983.
• Thompson, M.W., R. R. McInnus, and H. F. Willard.
  Thompson and Thompson Genetics in Medicine ,
  Fifth Edition. Philadelphia W.B. Saunders
  Company, 1991.
• Olivieri, N. F. "The Beta Thalassemias." The New
  England Journal of Medicine 341 (1999) 99-109.