ABSTRACT
Alpha-thalassemia [alpha-thal] is probably the most prevalent monogenic condition in the world. Deletions are the most common types of mutations in alpha-thal, followed by point mutations and small insertion/deletion. In the context of national screening program for prevention of thalassemia and hemoglobinopathies in Iran, alpha-thal carriers have come to more attention. Therefore, the frequency and distribution of alpha-globin mutations in various regions of the country have been studied in recent years. A comprehensive search was performed in PubMed, Scopus, and national databases for finding reports on mutation detection in alpha-thal carriers and HbH disease with Iranian origin. The mutation data of 10849 alpha-thal carriers showed that -alpha[3.7] and alpha[-5NT] were the most common deletional and nondeletional mutations, respectively. In HbH disease cases, the -alpha[3.7]/-[-MED] was the most prevalent genotype. Overall, 42 different mutations have been identified in alpha-globin cluster reflecting the high heterogeneity of the mutations in Iranian populations
ABSTRACT
Here we report the result of three cases referred to our lab that had a combination of beta-thalassemia and hemoglobin D [Hb D] traits. These individuals had no symptoms of profound anemia and hematological indices were similar to that of a beta-thalassemia heterozygote. In all three cases, the Hb D level was elevated and no HbA was detected electrophoretically. The electrophoresis pattern suggested that all cases were homozygotes for Hb D. PCR followed by digestion with EcoRI and sequencing of the beta-globin gene confirmed the presence of Cd 121 GAA>CAA in the heterozygous form with another beta-globin mutation. In all cases, the mutations in the beta-globin gene were detected by ARMS PCR technique and they were either IVSII-I or IVSI-5. Hematological studies of the family members showed that thalassemia which caused the mutations and Hb D were in the Trans position