What Are Thalassemias?
Thalassemias (thal-a-SE-me-ahs) are inherited blood
disorders. "Inherited" means they're passed on from parents to children through
Thalassemias cause the body to make fewer healthy
red blood cells and less hemoglobin (HEE-muh-glow-bin) than normal. Hemoglobin
is an iron-rich protein in red blood cells. It carries oxygen to all parts of
the body. It also carries carbon dioxide (a waste gas) from the body to the
lungs, where it's exhaled.
People who have thalassemias can have mild or severe
(uh-NEE-me-uh). This condition is caused by a lower than normal number of red
blood cells or not enough hemoglobin in the red blood cells.
Normal hemoglobin, also called hemoglobin A, has
four protein chainstwo alpha globin and two beta globin. The two major
types of thalassemia, alpha and beta, are named after defects in these protein
Four genes are needed to make enough alpha globin
protein chains. Alpha thalassemia trait occurs when one or two of the four
genes are missing. If more than two genes are missing, the result is moderate
to severe anemia.
The most severe form of alpha thalassemia is known
as alpha thalassemia major or hydrops fetalis. Babies with this disorder
usually die before or shortly after birth.
Two genes (one from each parent) are needed to make
enough beta globin protein chains. Beta thalassemia occurs when one or both
genes are altered.
The severity of beta thalassemia depends on how
badly one or both genes are affected. If both genes are affected, the result is
moderate to severe anemia. The severe form of beta thalassemia also is known as
thalassemia major or Cooley's anemia.
Thalassemias affect both males and females. They
occur most often among people of Italian, Greek, Middle Eastern, Asian, and
African descent. Severe forms usually are diagnosed in early childhood and are
Doctors diagnose thalassemias using
tests. The disorders are treated with
transfusions, medicines, and other procedures.
Treatments for thalassemias have improved greatly in
the past few years. People who have moderate and severe thalassemias are now
living longer and have better quality of life than before.
However, complications from thalassemias and their
treatments are frequent. People who have moderate or severe thalassemias must
closely follow their treatment plans. They need to take care of themselves to
remain as healthy as possible.