一种新的β地中海贫血基因突变类型的分子诊断和产前基因诊断

Molecular and prenatal diagnosis for a Chinese pregnant woman with a novel mutation of β thalassemia

目的 对产前地中海贫血筛查确诊为β地中海贫血的一对夫妇进行β珠蛋白基因突变分析,并对胎儿进行产前基因诊断.方法 根据血常规和血红蛋白分析进行地中海贫血的筛查,对筛查诊断为β地中海贫血患者采用聚合酶链反应/寡核苷酸探针反向斑点杂交法检测中国人常见的17个β珠蛋白基因突变类型.对于未发现常见突变者采用β珠蛋白基因DNA测序和变性高效液相色谱分析.结果 丈夫为CD41/42（-TCTT）突变杂合子,妻子携带一种迄今在中国人中未见报道的β地中海贫血基因突变IVS-Ⅰ-110（G→A）,产前诊断胎儿为IVS-Ⅰ-110（G→A）和CD41/42（-TCTT）突变双重杂合子,并进行引产.结论 β地中海贫血IVS-Ⅰ-110（G→A）突变的发现,丰富了中国人β地中海贫血基因突变种类,对遗传咨询和地中海贫血产前基因诊断具有重要意义.

Objective To conduct molecular and prenatal diagnosis for a couple with β thalassemia.Methods Blood routine examination and hemoglobin analysis were used for screening of thalassemia. Seventeen common Chinese mutations of β thalassemia were detected for the carriers with β thalassemia using PCR/RDB. The unknown mutation of β thalassemia was identified by DNA sequencing and DHPLC analysis. Results The husband was heterozygote of CD41/42（-TCTT）. The wife carried a mutation IVS- Ⅰ -110（G→A）of β thalassemia having not been reported in Chinese so far. The fetus was a double mutated heterozygote of IVS- Ⅰ -110（G→A）and CD41/42（-TCTT）. The pregnancy was terminated. Conclusion Mutation IVS- Ⅰ -110（G→A）of β thalassemia in Chinese is of importance to the genetic counseling and prenatal diagnosis of thalassemia.