Mild beta thalassaemia major in Singapore

Abstract

4 families with genetic evidence of β thalassemia major in the propositii and in some of their siblings are described. 2 families were Chinese, 1 Indian and 1 Malay. All the propositi behaved differently from the classical form of β thalassemia major, in that blood transfusions were unnecessary or not given at all, and that all were active physically, grew well and were alive in their late teens, 2nd and 3rd decades. The literature is reviewed with regard to such mild cases of β thalassemia major, but such patients have been of Negro or Southern European stock. For the first time, such cases have been described in Chinese, Malay and Indian ethnic groups of South East Asia. It is postulated that a mild state could arise from a different β thalassemia gene or a combination of such different genes. It could equally arise from a combination of α and β thalassemia genes in the same individual. In the families described in Singapore, the former is more probable as no evidence of an α thalassemia gene was found in these families.