Spectrum of β-thalassemia Mutations in Iran, an Update

β-thalassemia major (β –TM) is the most common thalassemia severe phenotype among Iranians. In recent years, molecular understanding of pathogenesis of β –TM has provided a great opportunity regarding diagnostic issues. Creating comprehensive molecular databases provides highly sensitive diagnostic tools for β –TM and effective prenatal diagnosis (PND) molecular screening tests. Despite a large body of research on molecular basis of β –TM, there are few review papers that consider a general view on the distribution of β –TM mutations in Iran. In the current review, common genetic defects identified in Iranian β –TM patients since 2005 to 2014 have been described. In addition, the prevalences and distributional trends of recognized mutations were discussed. It was found that IVSII-1 (G>A) and IVSI-5 (G>C) were by far the most frequent mutations detected in Iranian patients. Other common reported mutations included FSC 8/9 (+G), IVS I-110 (G>A), FSC 36/37 (–T), IVSI-1 (G>A), IVSI (-25bp), and codon 44 (-C). In conclusion, it was found that molecular profile of β –TM is highly variable among different Iranian populations; in particular, it seems that ethnicity and intra-migration can be most important participating factors in controlling distributional patterns.