黏多糖病Ⅱ型的产前诊断

Prenatal diagnosis of mucopolysaccharidosis type Ⅱ

目的应用胎儿羊水细胞艾杜糖一2一硫酸酯酶（idumnate-2-sulfatase，IDS）活性测定和基因突变检测的方法，对2例黏多糖病Ⅱ型（mucopolysaccharidosis type Ⅱ，MPSII）高危妊娠孕妇进行产前诊断。方法胎儿羊水细胞培养，测定其IDS活性，并抽取羊水细胞基因组DNA，做胎儿性别鉴定和IDS基因突变检测。结果2例胎儿羊水细胞IDS活性均明显下降，基因测序发现1例男性胎儿为IDS突变半合子，另1例女性胎儿为IDS基因突变携带者。结论胎儿羊水细胞酶活性测定结合基因突变分析是一种准确、可靠、灵敏的MPSⅡ产前诊断方法，可对高危妊娠孕妇作出快速的产前诊断。

Objective To establish a method of iduronate-2-sulfatase（IDS） activity assay and mutation analysis of IDS gene for the prenatal diagnosis of mucopolysaccharidosis type Ⅱ （MPS Ⅱ ）. Methods Prenatal diagnosis of two cases was performed using cultured fetal amniotic fluid cells. Enzyme activity of IDS in cultured fetal amniotie fluid cells extracted from the two pregnant women at high risk of MPS Ⅱ was measured. Meanwhile, genomic DNA was extracted for fetal gender testing and mutation analysis of the IDS gene. Results Enzyme activity assay showed that IDS activity in amniotic fluid cells was significantly decreased. IDS gene sequencing showed that the male fetus was hemizygous mutant, and the female fetus was carrier of heterozygous mutation. Therefore the male fetus was an MPS ]] patient and the female fetus was a mutation carrier. Conclusion Determination of IDS activity in fetal amniotie fluid cells together with IDS gene mutation analysis is a rapid, sensitive and accurate method of prenatal diagnosis of MPS Ⅱ. Using this method, prenatal diagnosis for pregnant women at high risk of MPS Ⅱcan be achieved.