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BMJ Open BMJ Open: first published as 10.1136/bmjopen-2015-010047 on 29 December 2015. Downloaded from Mutation Screening for Thalassaemia in the Jino Ethnic Minority Population of Yunnan Province, Southwest China ForJournal: peerBMJ Open review only Manuscript ID bmjopen-2015-010047 Article Type: Research Date Submitted by the Author: 20-Sep-2015 Complete List of Authors: Wang, Shiyun; Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth, Zhang, Rong; Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth, Xiang, Guangxin; National Engineering Research Center for Beijing Biochip Technology, Li, Yang; National Engineering Research Center for Beijing Biochip Technology, Hou, Xuhong; Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth, Jiang, Fusong; Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao http://bmjopen.bmj.com/ Tong University Affiliated Sixth, Jiang, Feng; Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth, Hu, Cheng; Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth, Jia, Weiping; Shanghai Jiaotong University Affiliated Sixth People’s Hospital, on September 26, 2021 by guest. Protected copyright. <b>Primary Subject Haematology (incl blood transfusion) Heading</b>: Epidemiology, Genetics and genomics, Haematology (incl blood Secondary Subject Heading: transfusion) Keywords: EPIDEMIOLOGY, Antenatal < GENETICS, Anaemia < HAEMATOLOGY For peer review only - http://bmjopen.bmj.com/site/about/guidelines.xhtml Page 1 of 22 BMJ Open BMJ Open: first published as 10.1136/bmjopen-2015-010047 on 29 December 2015. Downloaded from 1 2 3 4 1 Research article 5 6 2 Mutation Screening for Thalassaemia in the Jino Ethnic 7 8 9 3 Minority Population of Yunnan Province, Southwest China 10 11 4 12 13 1 1 2 2 1 14 5 Shiyun Wang , Rong Zhang , Guangxin Xiang , Yang Li , Xuhong Hou , Fusong 15 For peer review only 16 6 Jiang1, Feng Jiang1, Cheng Hu1,*, Weiping Jia1,* 17 18 19 7 20 21 8 1Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, 22 23 24 9 Shanghai Clinical Center for Diabetes, Shanghai Jiao Tong University Affiliated Sixth 25 26 10 People’s Hospital, Shanghai, 200233, People’s Republic of China. 27 28 2 29 11 National Engineering Research Center for Beijing Biochip Technology, Beijing, 30 31 12 200233, People’s Republic of China. 32 33 34 13 http://bmjopen.bmj.com/ 35 36 * 14 Corresponding authors: 37 38 39 15 Weiping Jia 40 41 16 E-mail: [email protected]; Tel: +86 21 24058260; Fax: +86 21 64368031 42 on September 26, 2021 by guest. Protected copyright. 43 44 17 Cheng Hu 45 46 18 E-mail: [email protected]; Tel: +86 21 24058924; Fax: +86 21 64368031 47 48 49 19 Keywords: 50 51 20 thalassaemia, gene mutation, haemoglobin, anaemia, Jino, Yunnan Province 52 53 54 21 Word count: 1,800 55 56 57 58 59 1 60 For peer review only - http://bmjopen.bmj.com/site/about/guidelines.xhtml BMJ Open Page 2 of 22 BMJ Open: first published as 10.1136/bmjopen-2015-010047 on 29 December 2015. Downloaded from 1 2 3 4 22 ABSTRACT 5 6 23 Objectives 7 8 9 24 This study aimed to detect α- and β-thalassaemia mutations in the Jino ethnic minority 10 11 25 population of Yunnan Province, southwest China. 12 13 14 26 Design 15 For peer review only 16 27 A total of 1,613 Jino adults were continuously recruited from February 2012 to April 17 18 19 28 2012. Fasting venous blood samples were obtained to determine haematological 20 21 29 parameters. Haemoglobin analysis was conducted via high-performance liquid 22 23 24 30 chromatography. Participants with hypochromic microcytic anaemia or positive 25 26 31 haemoglobin analysis profiles were confirmed via α- and β-globin genetic testing, 27 28 29 32 including DNA microarray analysis, direct sequencing methods and multiplex 30 31 33 gap-polymerase chain reaction assays. 32 33 34 34 Setting http://bmjopen.bmj.com/ 35 36 35 Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai 37 38 39 36 Jiao Tong University Affiliated Sixth People’s Hospital 40 41 42 37 Results on September 26, 2021 by guest. Protected copyright. 43 44 38 We found 363 suspected cases via primary screening of haematological parameters 45 46 39 and haemoglobin analysis. After further genetic testing, six types of α- and 47 48 49 40 β-thalassaemia mutations were detected in 203 out of 363 individuals. Both of α0- and 50 51 41 α+-thalassaemia mutations, - -SEA and - α3.7 were identified. Additionally, 13 Hb E 52 53 54 42 carriers had coexisting α0 or α+-thalassaemia deletions. Clinical haematological 55 56 parameters indicated that in this study, carriers of all thalassaemic genotypes had 57 43 58 59 2 60 For peer review only - http://bmjopen.bmj.com/site/about/guidelines.xhtml Page 3 of 22 BMJ Open BMJ Open: first published as 10.1136/bmjopen-2015-010047 on 29 December 2015. Downloaded from 1 2 3 4 44 more severe hypochromic microcytic anaemia compared with non-thalassaemic 5 6 45 individuals. 7 8 9 46 Conclusion 10 11 47 Our results provide information on the Jino ethnic minority that may be useful for 12 13 14 48 further genetic counselling, prenatal screening and clinical diagnosis of thalassaemia 15 For peer review only 16 49 in this region. 17 18 19 50 20 21 51 22 Strengths and limitations of this study: 23 24 52 1. As Jino, the last ethnic minority confirmed in China, was reported to have a high 25 26 53 prevalence of thalassaemia according to a previous research of children under 10 27 28 29 54 years old, this study aimed to detect the mutations of α- and β-thalassaemia in Jino 30 31 55 adults. 32 33 34 56 2. α- and β-thalassaemia mutation spectrum shown in this research may help to http://bmjopen.bmj.com/ 35 36 57 explain further genotype – phenotype correlations and to establish a thalassaemia 37 38 39 58 prevention program in this area. 40 41 59 3. The sample size of controls we used in the genetic testing was relatively small and 42 on September 26, 2021 by guest. Protected copyright. 43 44 60 may not have the validity to detect the other genotypes of silent α-thalassaemia 45 46 61 from this group. 47 48 49 62 50 51 63 52 53 54 55 56 57 58 59 3 60 For peer review only - http://bmjopen.bmj.com/site/about/guidelines.xhtml BMJ Open Page 4 of 22 BMJ Open: first published as 10.1136/bmjopen-2015-010047 on 29 December 2015. Downloaded from 1 2 3 4 64 INTRODUCTION 5 6 65 As a group of monogenic disorders, thalassaemia is a serious health problem 7 8 9 66 worldwide, especially in Mediterranean areas, Southeast Asia and southern China 10 11 67 [1-3]. Yunnan Province, which is located along the border areas of 12 13 14 68 China-Myanmar-Laos, is notable for its ethnic diversity. According to a survey of 15 For peer review only 16 69 children under 10 years old, several ethnic minorities in this region have a high 17 18 19 70 prevalence of thalassaemia, with the prevalence of α-thalassaemia (α-thal) being 20 21 71 highest (22.1%) in Dai from Xishuangbanna and the prevalence of β-thalassaemia 22 23 24 72 (β-thal) being highest in Achang (40.6%) [4]. 25 26 73 Jino is the last ethnic minority confirmed in China, and the prevalences of α-thal and 27 28 29 74 β-thal among Jino children are 3.1% and 29.3%, respectively. Thalassaemic children 30 31 75 can exhibit various clinical symptoms; some are asymptomatic carriers, whereas 32 33 34 76 others have severe haemolytic anaemia [5]. Blood transfusion therapy, which is http://bmjopen.bmj.com/ 35 36 77 needed for severe carriers, imposes a heavy burden on families and public health 37 38 39 78 management [6]. Although genetic screening is essential to prevent and control this 40 41 79 inherited disease, systematic investigations of thalassaemia mutations in Jino adults 42 on September 26, 2021 by guest. Protected copyright. 43 44 80 are rare. 45 46 81 The Jino population comprises nearly 20,000 individuals, and most (approximately 47 48 49 82 90%) live around Jino Mountain, which is located in east-central Yunnan Province [7]. 50 51 83 A large number of thalassaemic mutations have been found in the general population 52 53 54 84 worldwide [8-10]; however, little is known regarding this isolated population. Indeed, 55 56 the molecular mechanism and genetic variations of thalassaemia in Jino individuals 57 85 58 59 4 60 For peer review only - http://bmjopen.bmj.com/site/about/guidelines.xhtml Page 5 of 22 BMJ Open BMJ Open: first published as 10.1136/bmjopen-2015-010047 on 29 December 2015. Downloaded from 1 2 3 4 86 may be different from those in other ethnicities. Our study aimed to detect α-thal and 5 6 87 β-thal gene mutations in Jino adults to provide basic information for further prenatal 7 8 9 88 consulting and thalassaemia diagnosis. 10 11 89 12 13 14 90 MATERIALS AND METHODS 15 For peer review only 16 91 Participants and clinical screening 17 18 19 92 This cross-sectional study was conducted in eight villages of Jino Mountain Township 20 21 93 in southern Yunnan Province, China (Fig.