Mutation screening for thalassaemia in the Jino ethnic minority population of Yunnan Province, Southwest China

OBJECTIVES This study aimed to detect α- and β-thalassaemia mutations in the Jino ethnic minority population of Yunnan Province, Southwest China. DESIGN A total of 1613 Jino adults were continuously recruited from February 2012 to April 2012. Fasting venous blood samples were obtained to determine haematological variables. Haemoglobin analysis was conducted using high-performance liquid chromatography. Participants with hypochromic microcytic anaemia or positive haemoglobin analysis profiles were confirmed by α- and β-globin genetic testing, including DNA microarray analysis, direct sequencing methods and multiplex gap-PCR assays. SETTING Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Jiao Tong University Affiliated Sixth People's Hospital. RESULTS We found 363 suspected cases by primary screening of haematological variables and haemoglobin analysis. After further genetic testing, four types of α- and β-thalassaemia mutation were detected in 203 out of 363 individuals. Both α(0)- and α(+)-thalassaemia mutations, --(SEA) and -α(3.7), were identified. β-Thalassaemia mutations included CD17 (HBB:c.52A>T) and CD26 (HbE or HBB:c.79G>A). In addition, 13 HbE carriers had coexisting α(0)- or α(+)-thalassaemia deletions. Clinical haematological variables indicated that, in this study, carriers of all thalassaemic genotypes had more severe hypochromic microcytic anaemia than non-thalassaemic individuals. CONCLUSIONS Our results provide information on the Jino ethnic minority that may be useful for further genetic counselling, prenatal screening and clinical diagnosis of thalassaemia in this region.