Diagnosis of beta-thalassaemia carriers in the Sultanate of Oman

ABSTRACT

Haemoglobinopathies are a major cause of morbidity in the Sultanate of Oman and premarital screening is being encouragedin order to reduce the number of affected births. The identification of beta-thalassaemia carrier status is an essential prerequisite of any screening programme. However, the level of Haemoglobin [Hb] A[2], 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. The following study was undertaken to ascertain if the Hb A[2] level is an appropriate tool for the identification of beta-thalassaemia carriers in the Omani population. Hb A[2] was measured by high performance liquid chromatography [HPLC] in 160 obligate carriers of beta-thalassaemia. 158 subjects had Hb A[2] levels above 3.5% indicating beta-thalassaemia trait. Two subjects had slightly lower levels and were found to be iron deficient. After therapy both these subjects' Hb A[2] levels increased to above 3.5%. In the absence of iron deficiency, Hb A[2] is an accurate marker for the presence of beta-thalassaemia trait in the Sultanate of Oman