Laboratory tests for thalassaemia include a routine blood test known as a Complete Blood Count (CBC), which includes measuring the level of haemoglobin and other parameters related to the number and volume of red blood cells, known as Mean corpuscular Volume (MCV) and Mean Corpuscular Haemoglobin (MCH). MCV levels may be lower in children and vary according to age. Red blood cells are also examined under a microscope in order to examine their size and shape. The red blood cells of a thalassaemia carrier will be a paler shade of red and be various shapes (poikitocytosis), compared to normal red blood cells which are a darker red and round and concave in shape.
Tests to determine the presence of the β -trait and confirm that the individual is a carrier of β -thalassaemia include a laboratory process known as haemoglobin electrophoresis, which enables quantitative measurement of haemoglobin. Other haemoglobins normally present in adult red blood cells such as foetal haemoglobin (HbF) may also be measured by electrophoresis. In most cases, the above tests are sufficient to determine whether an individual is a carrier or not.
In some circumstances, genetic or DNA tests need to be carried out in order to confirm whether one is a carrier. Such genetic tests are beginning to be more and more widely used to test for the thalassaemia trait.
Screening should be considered when a relative is known to be a carrier or a thalassaemia patient. Moreover, people who are anemic and do not respond to iron treatment should also have their carrier status donetum orci ultrices non.