【摘要】 目的分析广西地区儿童中间型β珠蛋白生成障碍贫血(地贫)基因型和临床特点。方法采用PCR检测β及α地贫基因、Gγ珠蛋白基因启动子-158(G-γ158)位点单核苷酸多态性(SNP)和β类珠蛋白基因簇位点控制区Dnase I酶高敏位点基序2(-βLCR-HS2)AT重复序列多态性,并分析临床资料。结果基因型:1)7例为nt-28纯合子或双重杂合子,其中2例nt-28纯合子,1例βE/nt-28,2例β0/nt-28,1例β0/nt-28复合G-γ158(T),另1例β0/nt-28同时复合G-γ158(T)和--SEA型α地贫1基因;2)各有3例β0/β0并遗传G-γ158(T)或--SEA型α地贫1基因;3)1例β0/β0同时遗传--SEA型α地贫1基因和G-γ158(T);4)6个携带G-γ158(T)的病例其-βLCR-HS2均检出(AT)9N12(AT)10序列。临床表现:14例Hb(75.9±9.7)g/L,平均红细胞体积为(68.9±5.9)fL,Hb F均值66.9%±16.3%。除2例nt-28纯合子和1例βE/nt-28杂合子未输过血外,余病例均有较明显症状和不定期输血史。结论广西地区中间型β地贫主要基因修饰因素依次为nt-28(A→G)突变,G-γ158(T)和--SEA型α地贫1基因。-βLCR-HS2(AT)9N12(AT)10多态性形式在本组多见。nt-28纯合子和与βE构成的双重杂合子临床表现较轻。更多还原

【Abstract】 Objective To analyze genetic and clinical features of 14 children with β-thalassemia intermedia in Guangxi area.Methods β-thalassemia genes,α-thalassemia genes,single nucleotide polymorphism（SNP） at position-158 of（）^Gγ-globin gene,AT repeats polymorphisms of DNase I-hypersensitive site 2 of the β-globin gene cluster locus control region（β-LCR-HS2） were detected by PCR techniques.Clinical data were analyzed.Results Genotype:1.Seven cases were homozygous or compound heterozygous for nt-28（A→G）.Among them,2 cases′ genotypes were nt-28/nt-28,1 case was β^E/ nt-28,2 cases were β⁰/nt-28,1 case（β⁰/nt-28） co-inherited（）^Gγ158（T） and 1 case（β⁰/nt-28） co-inherited simultaneously（）^Gγ-158（T） and——SEA α-thalassemia-1 genes.2.Three cases with β⁰/β⁰ presented（）^Gγ-158（T）,and other 3 cases co-inherited——SEA α-thalassemia-1 genes.3.One patient with β⁰/β⁰ co-inherited（）^Gγ-158（T） and——SEA α-thalassemia-1 genes.4.Six cases carrying（）^Gγ-158（T） had（AT）₉ N₁₂（AT）₁₀ sequences in β-LCR-HS2.Phenotype:The values of Hb,MCV,HbF of 14 patients were（75.9±9.7） g/L,（68.9±5.9） fL,66.9%±16.3%,respectively.Except for 2 cases with genotypes of nt-28/nt-28 and 1 case with β^E/nt-28 who had never been transfused,the others had more severe symptoms and required irregularly transfusion.Conclusions In the 14 children with β-thalassemia intermedia from Guangxi area,nt-28（A→G）,（）^Gγ-158（T） and——SEA α-thalassemia-1 gene are main alleviating gene factors.Incidence of（AT）₉ N₁₂（AT）₁₀ sequence in β-LCR-HS2 in these patients is high.Patients who are homozygous for nt-28 or compound heterozygous for β^E have milder phenotypes.更多还原