Diagnosis of Beta-Thalassaemia Carriers in the Sultanate of Oman

Background: Haemoglobinopathies are a major cause of morbidity in the Sultanate of Oman and premarital screeningis being encouraged in order to reduce the number of affected births. The identification of (beta)-thalassaemia carrier status is an essentialprerequisite of any screening programme. However, the level of Haemoglobin (Hb) A2, which is used to detect (beta)-thalassaemia carriers,can be affected by other factors including iron deficiency, concurrent (alpha) thalassaemia and the type of DNA mutation present. Objectives:The following study was undertaken to ascertain if the Hb A2 level is an appropriate tool for the identification of (beta)thalassaemiacarriers in the Omani population. Method: Hb A2 was measured by high performance liquid chromatography (HPLC) in 160 obligatecarriers of (beta)-thalassaemia. 158 subjects had Hb A2 levels above 3.5% indicating (beta)-thalassaemia trait. Two subjects had slightly lowerlevels and were found to be iron deficient. After therapy both these subjects Hb A2 levels increased to above 3.5%. Conclusion: Inthe absence of iron deficiency, Hb A2 is an accurate marker for the presence of (beta)-thalassaemia trait in the Sultanate of Oman.