α-Thalassaemia is caused by the combination of 2 out of 7 mutations on the α - globin gene including SEA, THAI, HbCs, 3.7, 4.2, HbQs, C2delT, in which the SEA mutation accounted for 49.74%, HbCs accounted for 29.54% and 3.7 accounted for 8.58%.