Question

Give an account of the molecular genetic defects that underlie
thalassaemia and sickle cell disease.
What are the resulting clinical features of these conditions?
Describe the current status and future prospects of ONE of the following
genetic-based treatment options for these haemoglobinopathies:
(i) gamma-globin gene reactivation; (ii) gene therapy. (min 500words)

Answer 1

Thalassemia, an inherited blood disorder in which the body makes an abnormal form of hemoglobin. (Hemoglobin a protein molecule in red blood cells that carries oxygen). The disease results in excessive destruction of red blood cells, which leads to anemia

Other symptoms:

• bone deformities, especially in the face
• dark urine
• delayed growth and development
• excessive tiredness and fatigue
• yellow or pale skin

Sickle cell anemia is also an inherited form of anemia in which there is absence of enough healthy red blood cells to carry adequate oxygen throughout your body.

Normally, red blood cells are flexible and round, moving easily through blood vessels. In sickle cell anemia, the they become rigid and sticky and are shaped like sickles or crescent moons. These irregularly shaped cells can get stuck in small blood vessels, it leads to slow or block blood flow and oxygen to parts of the body.

symptoms :

Anemia

Episods of pain

painful swelling of hands and feet

Frequent infection

Delayed growth

Vision problems.

Genetic based treatments

Precently in gene therapy G-CSF mobilized CD34+ and also bone marro derived HSCs have been used .Specific concerns with G-CSF mobilization in patients with thalassemia include marked leukocytosis and thrombocytosis, and there is a chance of risk for potential thrombotic events in splenectomized patients.

In gamma globin gene rearrangement is very beneficial in sickle cell anemia in foelus. Single base substitutions in the promoter region of the gamma-globin genes provides its space for it