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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]

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]