RESUMO
ß-Thalassemia (ß-thal) is one of the most common autosomal recessive disorders worldwide. It is caused mainly by point mutations or, more rarely, deletions on the ß-globin gene, leading to reduced (ß+) or absent (ß0) synthesis of the ß chains of hemoglobin (Hb). Molecular characterization of ß-thal is essential for the prevention of this disease in the population. In China, more than 46 different mutations have been found, while approximately five large deletional types of ß-thal have been reported. Here we described a large deletional mutation of the ß-globin gene cluster previously unreported in the Chinese population, the 3.5 kb deletion (NC_000011.10: g.5224302-5227791del3490bp) removing the ß-globin gene promoter and the whole ß-globin gene leading to a ß0-thal phenotype.