Molecular spectrum of beta-thalassemia mutations in Northwestern Iran.

Beta-thalassemia (beta-thal) is a hereditary autosomal disorder with decreased or absent beta-globin chain synthesis. This study was designed to identify the common and rare beta-thal mutations in the Azerbaijan provinces, Northwestern Iran, and to set up a prenatal diagnostic laboratory. One hundred unrelated patients with known beta-thal major and intermedia, registered with the thalassemia clinics in the provincial capitals of Tabriz and Ardebil, were included. Mutations were studied in 200 chromosomes, by polymerase chain reaction-amplification refractory mutation system (PCR-ARMS) and direct sequencing methods. We found 17 beta-thal mutations in this region of Iran. The results showed that IVS-II-1 (-->GA) was the most frequent mutation, comprising 21% of all mutations. Other common mutations were IVS-I-110 (-->GA) 18%, frameshift codons (FSC) 8/9 (+G) 14.5%, FSC 8 (-AA) 8% and IVS-I-1 (GA) 7.5%. This is the first comprehensive study in this region and could be useful for developing a beta-thal molecular screening in Azerbaijan-Iran.