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Theβ-thalassaemia is hereditary autosomal disorders with decreased(β+) or absent(β0) (5%-30%)β-globin chain synthesis.The most common genetic defects inβ-thalassaemia are caused by point mutations or small deletions or insertions in HBB gene, which caused a substantial reducion of P-chain synthesis and a distinct haematological phenotye with hypochromic microcytic red blood cells,decreased osmotic fragility and characteristically raised levels of HbA2 in heterozygots. Theβ-thalassaemia is a highly heterogeneous inherited disorder distributed worldwide, which is found in Mediterranean,Africa, southeast Asia, Indian subcontinent and Southwest(Yunnan Dai,Jingpo)(20.00%), South of china. More than 200 such mutations are known at present.34 kinds of mutations are reported in China at present. CD41-42,IVS-Ⅱ-654,CD17,TATABbox-28,CD71-72和TATAbox-29 are common mutations. The distribution characteristics of HBB gene variation in each ethnic population are different, which have their own cluster of common mutations. Xishuangbanna-Dai of Yunnan inhabits Southwest of China, who locates Subtropicality. Only a few mutation of HBB gene were report in this place. In this study, the distribution characterization of variation in HBB gene ofβ-thalassemia in Dai minority group in Yunnan province was analyzed by DNA sequencing. In addition, to estnablish a rapid and economic method for screening mutation inβ-thalassemia by optimizing ARMS technique.Date showed:among the 209 samples, there are 9 variations detected, CD2 T>C (50.72%),CD26 G>A (35.41%),CD17 A>T (12.92%) JVS-Ⅱ-17 C>A (12.44%), IVS-Ⅱ-16 G>C (11.96%), IVS-Ⅰ-30 A>G (9.57%), CD6 T>A (9.09%), CD41-42 (-TCTT) (7.18%) and CD5 T>A (1.92%). There were 153 of 209 participants (73.21%) carrying HBB gene variation. Three common mutations, CD2, CD26 and CD17 can be efficiently detected by combining annealing condition and ARMS mismatch primers. The distribution of HBB gene variation in the Dai minority group inYunnan province were different from that of other groups in china. ARMS is a effective, convenient and economical technique for rapid detection of gene variation inβ-thalassemia.
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