Abstract
The Arab countries encompass a wide region stretching from the Persian Gulf to the Atlantic Ocean. The Arab population is quite heterogeneous and has experienced various invasions and migrations throughout history. β-thalassemia is endemic in all countries of the Arab world. Our review of the molecular basis of β-thalassemia in various Arab countries reveals the presence of 52 mutations, which are mostly of Mediterranean and Asian origin. The distribution of mutations reflects the geographical and historical backgrounds of each region. However, no specific mutation is confined to the Arabs, although some Arab countries do have unique mutations.