PRENATAL-DIAGNOSIS OF X-LINKED HYDROCEPHALUS IN A CHINESE FAMILY WITH4 SUCCESSIVE AFFECTED PREGNANCIES

We report on a woman with four successive pregnancies affected with X- linked hydrocephalus (XLH). The first child had prenatal craniocentesi s and died in utero. The second child had a postnatal shunting operati on, but suffers from severe growth and mental retardation at 5 years o f age. In the third pregnancy, prenatal ultrasound detected hydrocepha lus at the 16th and 20th weeks of gestation and the pregnancy was term inated. In the fourth pregnancy, ultrasound scanning at the 17th and 2 0th weeks of gestation revealed no remarkable findings, but hydrocepha lus was detected at the 24th week. Autopsy confirmed the prenatal diag nosis. DNA polymorphism analysis of the BclI site of exons 17-18 of fa ctor VIII gene of the woman and her last two fetuses seemed to be comp atible with a linkage between the XLH locus and factor VIII gene. Alth ough XLH has a variable presentation of ventriculomegaly, ultrasound s canning is still a useful tool for prenatal diagnosis at present. Earl ier and more accurate prenatal diagnosis will be feasible with molecul ar analysis of the XLH locus or its flanking regions.