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Background and Objectives Thalassemia is the most common monogenic disease worldwide inherited in autosomal recessive manner. Beta-thalassemia is caused by mutations in beta-globin gene. It is characterized by reduction in red blood cell indices including low MCV, low MCH, high RBC count, low HbA1 and high HbA2. Considering these symptoms, finding a relation between erythrocyte indices and kind of mutations can be used as a rapid method in mutation diagnosis and initial screening of carriers. Materials and Methods In this descriptive-analytical study after DNA extraction from 200 beta- thalassemia minors in Khuzestan province by salting out method, we amplified and sequenced beta-globin gene by Sanger sequencing. Finally, we analyzed statistically the beta-globin gene mutations and erythrocyte indices association by SPSS. Results Our results showed that IVSII-1(G > A) is the most common mutation with 22.5% frequency in this population of beta-thalassemia carriers. We found that MCV index variations have a meaningful association with beta-globin gene mutations and the highest mean of MCV (65.4 ± 3.7) was observed in IVSI-110(G > A) mutation. Conclusions The results comply with many other studies performed in this field and can be used for rapid detection of mutation in carrier parents and prenatal diagnosis. [ABSTRACT FROM AUTHOR]

Objective To evaluate the repercussions of recent changes to the cut-offs used in the first screening step of the pre-marital screening programme for thalassaemia prevention in Iran. Methods The profiles of 984 subjects referred to a genetic laboratory, and the tests of 242 parents of children with thalassaemia major were assessed for red blood cell (RBC) indices, haemoglobin (Hb) A2 levels and results of Hb electrophoresis. Results Of 407 suspected thalassaemia minor (STM) cases, 18 proved positive for thalassaemia minor on molecular analysis (18/407, confidence interval 2.6–6.9%). If the revised screening cut-offs had been used to determine who would undergo molecular analysis, two of these cases would not have been identified. Only 4.4% of suspected cases with lower than normal RBC indices (mean corpuscular volume <80 fl and mean corpuscular Hb <27 pg) and HbA2 (<3.5%) were diagnosed with thalassaemia minor. Conclusion The thalassaemia major prevention programme is performed in two separate steps. One step involves the screening of subjects and identification of β-thalassaemia minor, suspected cases for thalassaemia minor (STM), and normal subject groups. The other step concerns the identification of thalassaemia minor in the STM group. Changing the cut-offs at the first screening step does not result in significant improvement from an economic view, and is associated with significant risk at the second screening step. [ABSTRACT FROM AUTHOR]

Objective: Prenatal diagnosis of β-thalassemia carrier couples has helped to prevent bearing affected children. Among 177 couples referred to our laboratory for prenatal diagnosis, 14 mothers had twin pregnancies. Methods: By using direct and indirect methods, we determined their mutations and linkage analysis using polymorphic markers (restriction fragment length polymorphism [RFLP]). Results: It was shown that in five families both fetuses were heterozygote carriers. In another five families, one fetus was normal and the other one was carrier. In two families, one fetus was affected and the other one was heterozygous carrier; in one case one fetus was affected and the other one was homozygote normal. In the last family both fetuses were homozygote normal. If all fetuses were fraternal then one would expect to see seven homozygote normal and the same number affected, and 14 carriers. Conclusion: Our results indicated that at least in cases where both fetuses had identical genotypes, then they may be identical twins. Molecular testing indeed showed that in three cases the twins were identical. Another point is that in three cases, one of the twin fetuses was affected and the other one was either normal or heterozygote in which only the affected fetuses were aborted by the specialist. [ABSTRACT FROM AUTHOR]