Shiraz E-Med J. January 2014; 15(1): e19735. DOI: 10.17795/semj19735 Published online 2014 January 15. Research Article A Novel Mutation in the α2-Globin Gene in Two Unrelated Iranian Families Tayebeh Hamzehloei 1,* ; Farnaz Mohajer Tehran 2 ; Hosein Azimian 1 1 Medical Genetics Department, Mashhad University of Medical Sciences, Mashhad, IR Iran 2 Genetics Division, Ghaem Hospital, Mashhad University of Medical Sciences, Mashhad, IR Iran *Corresponding Author: Tayebeh Hamzehloei, Department of Medical Genetics, Mashhad University of Medical Sciences, Mashhad, IR Iran. Tel: +98-5118002248, Fax: +98-5118002248, E-mail: Hamzehloiet@mums.ac.ir Received: June 10, 2013; Revised: December 20, 2013; Accepted: April 10, 2014 Background: α-globin is encoded by two adjacent genes, αl and α2. Evidence suggests that these genes are not expressed equally and that the α2-globin gene encodes the majority of α-globin. This finding predicts that a thalassemic mutation of the α2-globin gene would result in a more severe loss of α-chain synthesis than a similar mutation in the αl-globin gene. Objectives: In the present study we described a novel non-deletion α-thalassemia defect in the 5'UTR region of the α2-globin gene. Materials and Methods: For molecular analysis, genomic DNA was isolated from peripheral blood cells by a salting out procedure. The common alpha deletion mutations were ruled out using the published primers and conditions. The amplification of the entire β and α1 globin genes was also carried out and their DNA was sequenced. No mutation was detected. Results: The mutation under study was located on an AP-1 transcription factor binding site and inherited in two unrelated Iranian families with hypochromic microcytic anemia. Conclusions: The patients in this study had moderate microcytosis and hypochromia without hemolysis, jaundice and splenomegaly. Molecular analysis in these patients revealed a non-deletion type of mutation in the promoter region, which is highly consistent with findings of other studies. Keywords: Alpha-Thalassemia; Mutation; Globin Implication for health policy/practice/research/medical education: In the present study we described a novel non-deletion α-thalassemia defect in the 5'UTR region of the α2-globin gene. Copyright © 2014, Shiraz University of Medical Sciences; Published by DOCS. This is an open-access article distributed under the terms of the Creative Commons At- tribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 1. Background Alpha-Thalassemia (-thal), one of the most common genetic disorders in the world, is characterized by defi- cient (+) or absent () synthesis of the alpha chain of the hemoglobin (Hb) molecule (1). Most -thal determinants are deletions involving one or both of the duplicated alpha-globin genes. However, non-deletion -thal muta- tions have been reported, which include termination codon mutations such as Hb Constant Spring (2), splic- ing defect caused by a 5-basepair (bp) deletion of the first intervening sequence (3), Hb Quong Sze, extremely un- stable a-globin structural variant (4, 5), single nucleotide substitution of the polyadenylation site (6), two nucleo- tide deletions at position -1 and -2 of the 5' untranslated region preceding the AUG codon (7), initiation codon mutation (AUG-ACG) (8) and nonsense mutation (a 116 GAG-UAG) (8). Apart from the -1, -2 deletion that occurs in a single a-globin gene chromosome, each of these muta- tions affects the 2 -globin gene. 2. Objectives Here, we report on a novel mutation in two unrelated families with moderate microcytosis aneamia. Sequenc- ing of the 2 and 1 globin genes revealed a novel heterozy- gous point mutation at the 5'UTR region of the 2 -globin gene. 3. Materials and Methods 3.1. Patients Among patients referred to the Genetic Antenatal Clinic at the Ghaem Hospital of Mashhad, two families showed an inherited novel mutation. Prior to any laboratory work, according to the ethics community, a written con- sent was obtained from all patients. In the first family, the proband (II-1) and her parents (I-1 and I-2) were studied (Table 1). The proband (II-1) and her mother (I-2) carried the mutation while the father (I-1) had a normal genotype. In the case of the second family (Table 2) the proband (II-1) and his mother (I-2) carried the mutation while his sister (II-2) had a normal genotype. The red blood cell (RBC) in- dices, and Hb A 2 and Hb F percentages were determined and alkaline electrophoresis on cellulose acetate and citrate agar electrophoresis were carried out according to standard procedures (9). The red cell lysates were also analyzed by isoelectric focusing (IEF) and exchanges high performance liquid chromatography (HPLC) (10).