经典型苯丙酮尿症家系8例产前诊断

Prenatal diagnosis in eight families with classic phenylketonuria

目的:建立一种利用苯丙氨酸羟化酶(PAH)基因内含子3中短串联重复序列(STR)多态性连锁分析进行经典型苯丙酮尿症(PKU)产前诊断的方法。方法:提取8例经典型PKU家系成员外周血DNA,提取4例胎儿羊水DNA,采用PCR-聚丙烯酰胺凝胶电泳-银染法进行连锁分析。结果:8例家系中4例可使用连锁分析方法进行精确产前诊断,4例胎儿为经典型PKU患者的可能性较小,出生后经新生儿筛查,证实为健康个体。2例家系仅能进行50%的排除诊断,2例家系无法进行产前诊断。结论:采用单个STR位点连锁分析能对部分经典型PKU家系有效进行产前诊断。

Aim ： To set up a method of prenatal diagnosis of classic phenylketonuria （PKU） by linkage analysis of the short tandem repeat（STR） in intron 3 linked to the phenylalanine hydroxylase （PAH） gene. Methods：DNA was extracted respectively from the blood samples of eight families＇members and amniotic fluid of four embryoes. The STR alleles of members in 8 families with classic form of PKU was analyzed and prenatal diagnosis were conducted using PCR together with PAGE and silver dying. Results： Accurate prenatal diagnosis was achieved in four families from eight classic PKU families. Four fetuses were received prenatal diagnosis and were reserved. The diagnosis was confirmed by biochemical tests in newborn. Of the four families in which accurate gene prenatal diagnosis was not achieved by PCR-STR, 50% exclusion prenatal diagnosis was achieved in two families, prenatal diagnosis was not achieved in the other two families. Conclusion： Prenatal gene diagnosis for classic PKU by STR is available for partly PKU families.