ICSH recommendations for the measurement of haemoglobin A2.

Although DNA analysis is needed for characterization of the mutations that cause β-thalassaemia, measurement of the Hb A(2) is essential for the routine identification of people who are carriers of β-thalassaemia. The methods of quantitating Hb A(2) are described together with pitfalls in undertaking these laboratory tests with particular emphasis on automated high-performance liquid chromatography and capillary electrophoresis.