The Spectrum of Α-Thalassemia Mutations in Kurdistan Province, West Iran
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Hemoglobin international journal for hemoglobin research ISSN: 0363-0269 (Print) 1532-432X (Online) Journal homepage: https://www.tandfonline.com/loi/ihem20 The Spectrum of α-Thalassemia Mutations in Kurdistan Province, West Iran Reza Alibakhshi, Keivan Moradi, Mozaffar Aznab, Zahra Dastafkan, Susan Tahmasebi, Mahsa Ahmadi & Leila Omidniakan To cite this article: Reza Alibakhshi, Keivan Moradi, Mozaffar Aznab, Zahra Dastafkan, Susan Tahmasebi, Mahsa Ahmadi & Leila Omidniakan (2020) The Spectrum of α- Thalassemia Mutations in Kurdistan Province, West Iran, Hemoglobin, 44:3, 156-161, DOI: 10.1080/03630269.2020.1768863 To link to this article: https://doi.org/10.1080/03630269.2020.1768863 Published online: 26 Jun 2020. Submit your article to this journal Article views: 4 View related articles View Crossmark data Full Terms & Conditions of access and use can be found at https://www.tandfonline.com/action/journalInformation?journalCode=ihem20 HEMOGLOBIN 2020, VOL. 44, NO. 3, 156–161 https://doi.org/10.1080/03630269.2020.1768863 ORIGINAL ARTICLE The Spectrum of a-Thalassemia Mutations in Kurdistan Province, West Iran Reza Alibakhshia, Keivan Moradia, Mozaffar Aznabb, Zahra Dastafkanc, Susan Tahmasebic, Mahsa Ahmadic and Leila Omidniakanc aDepartment of Biochemistry, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran; bDepartment of Hematology Oncology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran; cMedical Genetics Laboratory, Kermanshah University of Medical Sciences, Kermanshah, Iran ABSTRACT ARTICLE HISTORY In order to identify the a-thalassemia (a-thal) mutation spectrum in Kurdistan Province, West Iran, a Received 26 November 2019 total of 217 individuals, including 154 a-thal carriers and 63 normal subjects were investigated in this Revised 16 April 2020 study. Molecular analysis of a1- and a2-globin genes using multiplex gap-polymerase chain reaction Accepted 16 April 2020 (gap-PCR), amplification refractory mutation system (ARMS)-PCR or direct DNA sequencing, showed 11 a –a3.7 KEYWORDS different -globin variants. The (rightward) deletion (NG_000006.1: g.34164_37967del3804) a a polyA2 à -Thalassemia ( -thal); (70.32%), polyadenylation signal (polyA2) site (AATAAA>AATGAA) (a a)(HBA2:c.92A>G) (7.74%), 4.2 codon 59 gene; mutation; Kurds; –a (leftward) deletion (6.45%) and codon 59 (or Hb Adana) (G>A) (aa )(HBA1: c.179G>A) West Iran (4.52%) were the most frequent mutations in the present study. In conclusion, the spectrum of a-thal mutations in Kurdistan Province is closest to that in western provinces of Iran (Kurdish and Laki popula- tions). In addition, it was revealed that the codon 59 mutation is common in the Kurdish population. On the other hand, despite the same ethnic background of Kurds in Iran and Iraq, the ––MED I double gene deletion and polyA2 point mutation have different distributions in these two populations. Therefore, further studies are needed to identify the cause of these differences. Introduction diagnosis. Iran is a country located in the Middle East region. As many thalassemia carriers live in this country, the Deficiencies in the production of normal hemoglobin (Hb)- forming globin proteins result in a group of inherited blood National Thalassemia Screening Program has been estab- disorders called thalassemia [1]. a- And and b-thalassemia lished in Iran for more than 20 years [7]. The results of this (a- and b-thal) are due to mutations occurring on the screening program show different mutation spectra of a- HBA1/HBA2 and HBB genes, respectively. The prevalence of and b-globin genes in different geographic regions of Iran. thalassemia is high in Mediterranean, African, Middle In fact, given the presence of different ethnicities, it is not Eastern, Indian and Southeast Asian populations. surprising to see this diversity in Iran [1,8]. ‘ ’ Accordingly, an area called the Thalassemia Belt has Kurdistan Province is located in the western part of Iran. emerged [1,2]. According to the latest census of population and housing in To date, several mutations have been identified in a1- 2016, more than 1.6 million people live in Kurdistan and a2-globin genes and have been recorded in the HbVar database [3](http://globin.bx.psu.edu/hbvar/menu.html). Province. This province includes 10 counties, named More than 95.0% are deletional mutations [4]. Studies con- Sanandaj, Dehgolan, Saqqez, Marivan, Kamyaran, Baneh, ducted in different populations have shown that each popu- Divandarreh, Qorveh, Bijar and Sarvabad (https://www. lation has its own mutational spectrum. Thus, in each amar.org.ir). Kurdistan Province has borders to the north, particular population, there are a few mutations with high northeast, east and south with West Azerbaijan and Zanjan, allelic frequencies and a greater number of rare muta- Hamadan and Kermanshah provinces of Iran, respectively. tions [5]. In addition, it shares a border with Iraq in the west. People Given the high prevalence of patients with thalassemia in of Kurdistan Province speak the Kurdish language. To the populations living in the ‘Thalassemia Belt’ region and the best of our knowledge, no study has yet been in performed impact that these diseases may have on the quality of life of patients’ family members, various screening programs have in Kurdistan Province. Therefore, our aim in this study was a been implemented by different governments [6]. One of the to report the spectrum of -globin gene mutations in the main purposes of these screening programs is to identify Kurdish population living in the southern part of Kurdistan carriers and consequently the possibility of prenatal Province (Figure 1). CONTACT Dr. Reza Alibakhshi [email protected] Department of Biochemistry, School of Medicine, Kermanshah University of Medical Sciences, Parastar Street, Kermanshah, Kermanshah Province, Iran ß 2020 Informa UK Limited, trading as Taylor & Francis Group HEMOGLOBIN 157 Figure 1. The gray area on the map of Kurdistan Province, West Iran, represents the places of residence of the studied patients. Materials and methods of the entire HBA1/HBA2 genes (50 and 30 regulatory sequences as well as all exons and introns) was performed in During the period from 2009 to 2019, 154 a-thal carriers TM an ABI PRISM 3130 DNA analyzer (Applied Biosystems, from the southern part of Kurdistan Province (the counties Foster City, CA, USA). The data were analyzed using DNA of Sanandaj, Qorveh, Dehgolan, Marivan, Sarvabad and sequencing analysis version 5.2 software. Sequences of pri- Kamyaran) were referred to the Kermanshah Central mers are available upon request. Laboratory (Reference), Kermanshah, Kermanshah Province, Statistical data analysis was carried out using the a Iran, for the investigation of their -globin gene mutations. Statistical Package for the Social Sciences software, version a The -thal carriers were diagnosed based on their blood 25.0 (https://ibm.com/SPSS-Statistics/). The p values of < indices including mean corpuscular volume (MCV) 80.0 fL <0.05 were considered to be significant for all described < and/or mean corpuscular Hb (MCH) 27.0 pg, and Hb A2 tests. The v2 and independent Student t-test were used to < 3.5%, as well as lack of iron deficiency. In addition to compare categorical variables and mean levels of age and a -thal carriers, 63 subjects (siblings of carriers) with normal hematological factors between carriers and normal subjects, blood indices were chosen as the control group. An respectively. In addition, the analysis of variance (ANOVA) informed patient consent form was obtained from all of the and Scheffe post-hoc analysis were performed to determine participants. Approval was obtained from the Ethics the significance of differences between hematological factors Committee of Kermanshah University of Medical Sciences, in normal genotypes with a-thal genotypes identified in Kermanshah, Kermanshah Province, Iran [Ethics Code: our study. IR.KUMS.REC.1398.731]. We used three different molecular methods to identify the a-thal-causing mutations: 1) multiplex gap-polymerase Results –a3.7 chain reaction (gap-PCR) for detection of (rightward) A total of 217 individuals including 154 a-thal carriers and –a4.2 (NG_000006.1: g.34164_37967del3804), (leftward), and 63 normal subjects were investigated to identify a-globin ––MED I (NG_000006.1: g.24664_41064del16401) deletions; gene mutations. In order to evaluate the gender differences 2) amplification refractory mutation system (ARMS)-PCR in the mean levels of hematological factors, an independent aÀ5nta HBA2 þ þ for detection of ( : c.95 2_95 6delTGAGG), Student t-test was performed separately in both patient and polyadenylation signal A2 (polyA2) site (apolyA2a) à control groups (Table 1). According to the obtained results, (AATAAA>AATGAA) (HBA2:c.92A>G), polyA1 no statistically significant differences were observed in the apolyA1a A> G HBA2 ( ) (AATAA AATAA ) (T-Saudi) ( : mean of Hb A2, MCV and MCH levels between males and à codon 59 c. 94A>G), codon 59 (A>G) (or Hb Adana) (aa ) females (p > 0.05). However, the mean levels of Hb and red codon 19 (HBA1: c.179G>A), and codon 19 (–G) (a a)(HBA2: blood cell count (RBC) were significantly lower in females c.56delG); 3) direct DNA sequencing of the a1- and a2-glo- than those in males (p < 0.0001). On the other hand, as bin genes for the analysis of samples whose mutations were shown in Table 2, there was no statistically significant differ- a not in the list of mutations examined by the gap-PCR and ence in Hb A2 levels between -thal carriers and normal ARMS-PCR methods. The protocols and PCR cycling condi- subjects (p > 0.05). Moreover, MCV, MCH and Hb were sig- tions have been described by us in detail in our previous nificantly lower and RBC was significantly higher in a-thal studies [9,10] as well as by the Tan et al. [11] study. Briefly, carriers than those in normal subjects (p < 0.0001 for MCV, after purification of PCR products using QIAquick (Qiagen MCH and RBC, and p < 0.001 for Hb).