Objective To explore the gene sequencing and prenatal diagnosis of Glanzmann thrombasthenia (GT). Methods The blood samples were drawn from one case of phenotype GT pediatric patient, patient’s parents, and one normal control. The amniotic lfuid and cord blood from the fetus of patient’s mother were collected. When the fetus was born 2 days, the blood was drawn. The coagulation routine test and platelet aggregation test were performed. The expression of platelet membrane glycoprotein (GP) IIb and GPIIIa were tested by lfow cytometry. Microsatellite technology is used to determine whether fetal cord blood is contaminated with maternal cells. The expressed region and the junctional zone between exon and introns of GPIIb and GPIIIa were ampliifed by PCR technology from blood sample of patient, patient’s parents, and fetus’s cord and 2 days after birth. The PCR products were then subjected to DNA sequencing. Results Adenosine diphosphate (ADP) cannot induce the platelet aggregation in the patient. The max rate of the platelet aggregation in the fetus’s cord blood was half of the normal. However, the max aggregation rate induced by ADP in the blood sample of parents and fetus 2 days after birth were equal to normal. The mean lfuorescence intensity (MnX) of platelet membrane GPIIb and GPIIIa in the patient were 10%and nearly zero of the normal control, respectively, while those in the parents, the fetus’s cord blood and 2 days after birth were more than 90%and 30%to 50%of the normal control. The cast-off cells in amniotic lfuid and the DNA in cord blood analysis by microsatellite technology conifrmed that the amniotic lfuid and cord blood not contaminated by maternal cells. Gene analysis showed the heterozygosis mutation in exon6 A3829→C and exon9 G42186→A of the patient’s GPIIIa led to the amino acid heterozygosis mutation in GPIIIaHis281→Tyr and Cys400→Pro. These two mutations came from the father and the mother separately. However, there was only one heterozygosis mutation in exon9 G42186→A in the cast-off cells in amniotic lfuid, the fetus’s cord and blood 2 days after birth. Conclusion This GT patient have double heterozygosis mutation. The fetus has heterozygosis mutation conifrmed after birth.%目的：探讨血小板无力症（GT）的基因测序与产前诊断。方法采集1例表型GT患儿、父母及1例正常对照者的静脉血，患儿母亲腹中孕23周胎儿的脐带血和羊水，及其出生2 d时的静脉血。检测患儿、患儿父母、胎儿脐血及正常对照者的血凝常规和血小板聚集试验；流式细胞仪检测血小板膜糖蛋白（GP）IIb和GPIIIa的表达；微卫星技术确定胎儿脐血是否被母体细胞污染；PCR技术扩增患儿及其父母，以及胎儿及出生2 d静脉血GPIIb、GPIIIa所有外显子以及外显子和内含子交界区,扩增产物直接测序。结果二磷酸腺苷（ADP）不能诱导患儿的血小板发生聚集，胎儿脐血中ADP诱导的血小板最大聚集率约为正常人一半，患儿父母和胎儿出生2 d的ADP诱导的血小板最大聚集率与正常血小板聚集率相当。患儿血小板膜表面GPIIb、GPIIIa的的平均荧光强度（MnX）分别约为正常对照的10%及0，而患儿父母、胎儿脐血和胎儿出生2 d的MnX分别为正常对照的90%以上和30%~50%。羊水胎儿脱落细胞和脐血DNA微卫星分析证实胎儿羊水、脐血未被母体细胞污染；基因分析结果显示，患儿GPIIIa 6号外显子A38293→C和9号外显子G42186→A的杂合突变，导致GPⅢaHis281→Tyr和Cys400→Pro氨基酸的杂合改变。这两个突变分别来源于父亲和母亲。羊水胎儿脱落细胞、脐血或出生2 d静脉血中只有1个GPIIIa9号外显子G42186→A的杂合突变。结论 GT患儿GPIIIa的基因为双重杂合突变；胎儿出生后确证为GPⅢa基因杂合突变。
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