El-Shanshory Mr, Hagag Aa, Shebl Ss, Badria Im, Abd Elhameed Ah, Abd El-Bar Es, Al-Tonbary Y, Mansour A, Hassab H, Hamdy M, Alfy M, Sherief L, Sharaf E
Pediatric Department, Tanta University, Egypt.
Clinical Pathology Department, Tanta University, Egypt.
Mediterr J Hematol Infect Dis. 2014 Nov 1;6(1):e2014071. doi: 10.4084/MJHID.2014.071. eCollection 2014.
The molecular defects resulting in a β-thalassemia phenotype, in the Egyptian population, show a clear heterogenic mutations pattern. PCR-based techniques, including direct DNA sequencing are effective on the molecular detection and characterization of these mutations. The molecular characterization of β-thalassemia is necessary for carrier screening, genetic counseling, and to offer prenatal diagnosis.
was to evaluate the different β-globin gene mutations in two hundred β-thalassemic Egyptian children.
This study was carried out on two hundred β-thalassemic Egyptian children covering most Egyptian Governorates including 158 (79%) children with thalassemia major (TM) and 42 (21%) children with thalassemia intermedia(TI). All patients were subjected to meticulous history taking, clinical examination, complete blood count, hemoglobin electrophoresis, serum ferritin and direct fluorescent DNA sequencing of the β-globin gene to detect the frequency of different mutations.
The most common mutations among patients were IVS I-110(G>A) 48%, IVS I-6(T>C) 40%, IVS I-1(G>A) 24%, IVS I-5(G>C)10%, IVS II-848 (C>A) 9%, IVS II-745(C>G) 8%, IVS II-1(G>A) 7%, codon "Cd"39(C> T) 4%, -87(C>G) 3% and the rare mutations were: Cd37 (G>A), Cd8 (-AA), Cd29(-G), Cd5 (-CT), Cd6(-A), Cd8/9(+G), Cd 106/107(+G), Cd27(C>T), IVS II-16(G> C), Cd 28 (-C), Cap+1(A>C), -88(C>A), all of these rare mutations were present in 1%. There was a considerable variation in phenotypic severity among patients resulting from the interaction of different β(∘) and β+mutations. Furthermore, no genotype-phenotype association was found both among the cases with thalassemia major and the cases with thalassemia intermedia.
Direct DNA sequencing provides insights for the frequency of different mutations in patients with β-thalassemia including rare and/or unknown ones. The most common mutations in Egyptian children with beta thalassemia were IVS I-110(G>A) 48%, IVS I-6(T>C) 40%, IVS I-1(G>A)24%, IVS I-5(G>C)10%, IVS II-848 (C>A) 9%, IVS II-745(C>G) 8%, IVS II-1(G>A) 7%.
在埃及人群中，导致β地中海贫血表型的分子缺陷呈现出明显的异质性突变模式。基于聚合酶链反应（PCR）的技术，包括直接DNA测序，对于这些突变的分子检测和特征分析是有效的。β地中海贫血的分子特征分析对于携带者筛查、遗传咨询以及提供产前诊断是必要的。
评估200名埃及β地中海贫血儿童中不同的β珠蛋白基因突变情况。
本研究对200名埃及β地中海贫血儿童进行，这些儿童来自埃及的大部分省份，其中包括158名（79%）重型地中海贫血（TM）患儿和42名（21%）中间型地中海贫血（TI）患儿。所有患者均接受了详细的病史采集、临床检查、全血细胞计数、血红蛋白电泳、血清铁蛋白检测以及β珠蛋白基因的直接荧光DNA测序，以检测不同突变的频率。
患者中最常见的突变是IVS I-110（G>A）48%、IVS I-6（T>C）40%、IVS I-1（G>A）24%、IVS I-5（G>C）10%、IVS II-848（C>A）9%、IVS II-745（C>G）8%、IVS II-1（G>A）7%、密码子“Cd”39（C>T）4%、-87（C>G）3%；罕见突变有：Cd37（G>A）、Cd8（-AA）、Cd29（-G）、Cd5（-CT）、Cd6（-A）、Cd8/9（+G）、Cd 106/107（+G）、Cd27（C>T）、IVS II-16（G>C）、Cd 28（-C）、Cap+1（A>C）、-88（C>A），所有这些罕见突变均占1%。由于不同的β（∘）和β+突变相互作用，患者的表型严重程度存在相当大的差异。此外，在重型地中海贫血病例和中间型地中海贫血病例中均未发现基因型与表型的关联。
直接DNA测序为β地中海贫血患者不同突变的频率提供了见解，包括罕见和/或未知突变。埃及β地中海贫血儿童中最常见的突变是IVS I-110（G>A）48%、IVS I-6（T>C）40%、IVS I-1（G>A）24%、IVS I-5（G>C）10%、IVS II-848（C>A）9%、IVS II-745（C>G）8%、IVS II-1（G>A）7%。
Zotero 插件