Haemoglobin E Trait
What does it mean to carry haemoglobin E (AE)?
Haemoglobin E is an unusual haemoglobin that is common among people who originate from North East India, Bangladesh, Burma and South East Asia. It occurs occasionally among people of Turkish or Middle Eastern origin, and very rarely in other population groups. Haemoglobin E is diagnosed by a combination of microcytosis (low MCV<80fl and MCH<27pg) and electrophoresis.
Haemoglobin disorders are recessively inherited. People who carry one gene for haemoglobin E (heterozygotes) are popularly called carriers of haemoglobin E, or said to be “AE” or have a Haemoglobin E trait.
People who carry Haemoglobin E inherited it from one of their parents, and may pass it to their children. They will always carry it. It will not develop into a serious anaemia.
Can haemoglobin E cause any health problems for carriers?
Some carriers have a mild anaemia but the majority have a haemoglobin level in the normal range. Carriers are no more likely to become ill than other people and can do any kind of work. Haemoglobin E carriers are as healthy as other people. They are no more likely to become ill than other people. They can do any kind of work they choose. A few carriers have a mild anaemia, but the majority have an Haemoglobin in the normal range.
The most important health problem for carriers is the risk of iatrogenic iron overload. Microcytosis and mild anaemia can lead to an erroneous diagnosis of iron deficiency anaemia, and years of unnecessary iron medicines. A serum iron or serum ferritin measurement is the only way to make a diagnosis of iron deficiency in a person who carries haemoglobin E.
Carriers are as likely to become iron deficient as anyone else, particularly during pregnancy, when iron supplements may be needed.
Why is it important to know you carry haemoglobin E?
Although carrying Haemoglobin E does not affect their own health, carriers risk having children with a serious haemoglobin disorder. This can happen only if their partner carries another haemoglobin, called beta thalassaemia. It is important to know about this risk, because it can be avoided.
If your patient has a partner and is thinking of having children, it is important for your patient to tell the partner about Haemoglobin E trait, and ask him or her to have a blood test for haemoglobinopathy (4mls EDTA).
If this test shows the partner is not a carrier, there is no risk of having a child with a serious haemoglobin disorder. If the test shows the partner is also a carrier, the couple should be referred to a specialist thalassaemia counsellor, or regional Medical Genetics Centre, to discuss their reproductive options, including prenatal diagnosis.
Is there anything else you should do now?
If your patient has brothers or sisters or children, they may also carry haemoglobin E. They should also be offered a blood test.
