For β-Thalassemia by PCR
Thalassemia is an inherited autosomal recessive blood disease. In thalassemia, the genetic defect results in reduced rate of synthesis of one of the globin chains that make up hemoglobin. Reduced synthesis of one of the globin chains can cause the formation of abnormal hemoglobin molecules, thus causing anaemia, the characteristic presenting symptom of the thalassemias.
Thalassemia is a quantitative problem of too few globins synthesized, whereas sickle-cell anemia (a hemoglobinopathy) is a qualitative problem of synthesis of an incorrectly functioning globin. Thalassemias usually result in underproduction of normal globin proteins, often through mutations in regulatory genes. Hemoglobinopathies imply structural abnormalities in the globin proteins themselves. The two conditions may overlap, however, since some conditions which cause abnormalities in globin proteins (hemoglobinopathy) also affect their production (thalassemia). Thus, some thalassemias are hemoglobinopathies, but most are not. Either or both of these conditions may cause anemia.
The disease is particularly prevalent among Mediterranean people including people from the Middle East and North Africa.
Normal hemoglobin is composed of two chains each of α and β globin. Thalassemia patients produce a deficiency of either α or β globin (and accordingly thalassemias are classified into α and β thalassemia), unlike sickle-cell disease which produces a specific mutant form of β globin.
Interpretation of β-globin mutations assay for β-thalassemia by PCR:
For each polymorphic position, one of three possible staining patterns may be obtained:
1. Normal genotype
2. Mutant probe positive: heterozygous genotype (carrier individual)
3. Mutant probe positive: homozygous mutant genotype (affected individual)
Now in Saridar Lab, detection of 22 β-globin mutations for β-thalassemia by PCR is now available and the run out time is only 48 hours.