Geifman-Holtzman O, Bernstein I M, Berry S M, Bianchi D W, Holtzman E J
Division of Genetics, Maternal-Fetal Medicine, Health Science Center, Syracuse, New York, USA.
Prenat Diagn. 1996 Jun;16(6):489-93. doi: 10.1002/(SICI)1097-0223(199606)16:6<489::AID-PD894>3.0.CO;2-B.
The successful prophylaxis of RhD disease has brought attention to other Rh antigens, such as RhE antigen, that can cause hydrops fetalis. Our purpose was to develop simple molecular techniques to permit fetal RhE genotyping. We obtained amniotic fluid, villi, and fetal blood from two RhE-sensitized pregnancies, performed the Polymerase Chain Reaction (PCR), and made a presumptive fetal genotype diagnosis. The restriction enzyme MnlI was used to determine the E/e subtypes. DNA sequencing was used to demonstrate base-pair differences between the mother and fetus in one case. Conventional serology was used to confirm the fetal blood type. Maternal, paternal, and fetal genotypes were identified using molecular techniques. The presence of the fetal E allele was correctly predicted in both cases. Sequencing of maternal and fetal PCR products in one case demonstrated one base-pair substitution associated with the E/e polymorphism. Prenatal diagnosis of the fetal RhE genotype is now possible by PCR. The use of amniocytes obtained in one procedure of amniocentesis for RhE genotyping in sensitized pregnancies is less invasive than currently accepted techniques of cordocentesis, or serial amniocenteses done for delta OD450 measurement.
RhD疾病的成功预防已使人们关注到其他可导致胎儿水肿的Rh抗原，如RhE抗原。我们的目的是开发简单的分子技术以进行胎儿RhE基因分型。我们从两例RhE致敏妊娠中获取羊水、绒毛和胎儿血液，进行聚合酶链反应（PCR），并做出胎儿基因型的初步诊断。使用限制性内切酶MnlI来确定E/e亚型。在一例中使用DNA测序来证明母亲和胎儿之间的碱基对差异。使用传统血清学来确认胎儿血型。使用分子技术鉴定母亲、父亲和胎儿的基因型。两例均正确预测出胎儿E等位基因的存在。在一例中对母亲和胎儿的PCR产物进行测序，显示出一个与E/e多态性相关的碱基对替换。现在通过PCR可进行胎儿RhE基因型的产前诊断。在致敏妊娠中，利用羊膜穿刺术一次获取的羊水细胞进行RhE基因分型，比目前公认的脐血穿刺术或为测量ΔOD450而进行的系列羊膜穿刺术侵入性更小。
