HEALTHNET

What is thalassaemia minor?

Q. I was told that I have thalassaemia minor. What is it? How does it affect my health?

A. The thalassaemias are a group of anaemias caused by a genetic defect in the production of haemoglobin. Haemoglobin can carry oxygen and carbon dioxide because of its unique structure. It consist of two parts, the haem part contains iron. The globin part consists of 2 pairs of protein sections, the alpha and beta globin chains. Alpha thalassaemia results from a defect in the alpha chain and beta thalassaemia the beta chain.

The structures of these globin chains are controlled by a number of genes passed onto us from our parents. Since many genes are involved and many types of defects are possible, there are many types of thalassaemias of various severities.

Fortunately our genes come in pairs, one from each parent. One healthy gene can often effectively cover for the defects of the other. This is the case with thalassaemia minor. Persons with thalassemia minor, or thalassaemia trait, have very mild anaemia, or not at all. They enjoy a normal life span and are healthy in every aspect, until you look at things under the microscope - their red blood cells appear much smaller. Nowadays blood counts (called CBC, complete blood count) are done by machines, and this is reflected by a decreased reading in the index MCV (Meaning: Mean Corpuscular Volume, which reflects the average size of the red cells).

If both parents carry the same genetic trait, there can be a 25% chance to give birth to a child with thalassaemia major, a crippling form of anaemia which can be fatal in childhood.

The thalassaemia trait is very common in Southeast Asia, China, The Indian subcontinent, Asia Minor and the Mediterranean. It is believed that the people with this trait are less susceptible to malaria which is a kind of disease transmitted by mosquitoes.

Source: Quality HealthCare