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β-Thalassemia (β-thal) is one of the most common diseases in Iran. Here, we report the spectrum of HBB gene mutations in 176 Kurdish β-thal carriers from the northern part of Ilam Province, Iran. The amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) technique was used to identify common β-globin gene mutations observed in Iran. Samples negative on ARMS-PCR were analyzed by direct sequencing of the β-globin gene. In total, 12 different mutations were identified on the β-globin gene. The mutations of IVS-II-1 (G>A) (HBB: c.315+1G>A), codons 8/9 (+G) (HBB: c.27_28insG), codons 36/37 (–T) (HBB: c.112delT) and IVS-I-110 (G>A) (HBB: c.93-21G>A), were the most prevalent mutations in our samples, with frequencies of 59.09, 10.80, 7.95 and 7.39%, respectively. In general, the mutation spectrum of the β-globin gene in the northern part of Ilam Province is most similar to that in other western provinces of Iran. On the other hand, due to the high prevalence of carriers and β-thal major (β-TM) patients in this province, our results can be helpful in identifying carriers as well as at-risk fetuses through the prenatal diagnosis program. [ABSTRACT FROM AUTHOR]

The major defect in α-thalassemia (α-thal) is a single or double gene deletion. The aim of this study was to evaluate the α-thal mutations in two provinces of Southern Iran, Fars & Kohkeloye and Bouyer Ahmad. A total of 2000 subjects with microcytic hypochromic anemia was selected as a study group; finally, 1177 subjects were found to be α-thal mutation carriers by gap-polymerase chain reaction (gap-PCR) protocols and were confirmed by multiplex PCR and reverse hybridization test strips. A total of 1195 mutated α-globin alleles was identified in these patients that includes at least 10 different gene mutations. The most common mutation found was -α3.7 (rightward deletion) (71.7%%) and α−5 nt (IVS-I, -TGAGG) and the polyadenylation signal site (poly A1; AATAA A>AATAA G) were the second and third most common mutations (7.0 and 4.2%%, respectively). In countries like Iran, with a high prevalence of thalassemia, identifying different mutations is helpful in carrier screening, genetic counseling and prenatal diagnosis of at-risk couples for the prevention of the birth of babies affected by severe thalassemic anomalies. [ABSTRACT FROM AUTHOR]

Hb Constant Spring (Hb CS, codon 142, TAA>CAA, α2) (HBA2:c.427T>C) and α2 IVS-I donor site (GAGGTGAGG>GAGG - - - - -) (HBA2:c.95++2_95++6delTGAGG) are nondeletional α-thalassemia (α-thal) mutations found all over the world. Identification of α-thal genotypes in at-risk couples for severe anemia or in highly heterogeneous populations requires rapid, accurate and cost-effective genotyping methods. In this study, a pair of primers were used to specifically amplify an 883 bp fragment from the α2-globin gene in order to simultaneously identify these two mutations by a PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) method. We determined the genotypic frequencies of Hb CS and the α2 IVS-I donor site mutations after amplification and enzymatic digestion with Tru9I in 238 northern Iranian samples referred for α-thal testing. Hb CS and the α2 IVS-I donor site mutations accounted for 21 (8.8%%) and 29 (12.2%%) of the nondeletional cases. This genotyping assay has proven to be a rapid, reliable and useful diagnostic tool for simultaneous detection of these two anomalies for genetic counseling or further prenatal diagnosis. [ABSTRACT FROM AUTHOR]

We report the spectrum of ββ-thalassemia (ββ-thal) mutations observed in a cohort of at-risk couples, who presented for prenatal diagnosis at the Thalassemia, Hemophilia and Prenatal Diagnosis Genetic Research Center, Shiraz Medical University, Fars, Iran, from March 2001 to April 2002. Using polymerase chain reaction-amplification refractory mutation system (PCR-ARMS), restriction fragment length polymorphism (RFLP) and direct sequencing technologies, in different combinations, we were able to provide preventive medical abortions to 55 couples at-risk of having an affected fetus. Fetal samples of chorionic villus (63.6%%) or amniocentesis (37.6%%) were collected according to the gestational age. The average presentation age was 11.6 ±± 2.6 weeks. The expected prevalent mutations were IVS-II-1 (G>A, 23.6%%) and IVS-I-110 (G>A, 10.0%%) followed by IVS-I-5 (G>C, 6.4%%) and IVS-I, 25 bp deletion (8.2%%). [ABSTRACT FROM AUTHOR]

β-Thalassemia (thal) is one of the most common autosomal recessive disorders in Iran. There are more than two million carriers of β-thal and over 15,000 people affected with β-thal major who live in Iran. Prevalent mutations were identified by examining genomic DNAs isolated from 392 blood samples of β-thal carriers from three northern provinces of Iran. Furthermore, 172 pregnant women were analyzed from the 196 couples who requested pregnant diagnosis for β-thal. Allele identification was carried out using routine reverse dot-blot, amplification refractory mutation system (ARMS), and genomic sequencing. The most common mutation, IVS-II-1 (G→A), is followed, in order of frequency, by codon 30 (G→C), frameshift codons (FSC) 8,9 (+G), FSC 22/23/24 (-AAGTTGG), IVS-I-110 (G→A), IVS-I-5 (G→C), IVS-II-745 (C→G), IVS-I-2 (T→C), FSC 8 (-AA), IVS-I,3'-end (-25 bp), IVS-I-1 (G→A), FSC 36/37 (-T), IVS-I-6 (T→C), FSC 5 (-CT), -28 (A→C), codon 37 (G→A), IVS-II-2,3 (+11/-2), -30 (T→A), and -88 (C→A). We have also revealed the existence of five new mutations from northern Iran, one of which (codon 37) is the first reported for Iran. Furthermore, the rate of unknown mutations is significantly reduced in our study (about 6%). These results could help with establishing a center for prenatal diagnosis, prevention, and control of thalassemia in the northern provinces of Iran. [ABSTRACT FROM AUTHOR]