Prenatal diagnosis of haemophilia.
Prenatal diagnosis of haemophilia A or B is possible by means of chorionic villus biopsy in the first trimester which traces the mutation or informative genetic markers. If possible, direct gene analysis of the mutation is preferred. The natural starting point in haemophilia A is to ascertain whether the disease is due to inversion in the X-chromosome, which is the case in almost half of the severe cases. In haemophilia B, most families carry a unique mutation which needs to be characterized. In the immediate future, much of the prenatal diagnosis will be based on indirect genetic markers, repeats or polymorphisms, of the F.VIII and IX genes. Today chorionic villus sampling is the most widely used method but amniotic fluid, fetal blood and pre-implantation genetic diagnostics can also be used in selected cases. Prenatal diagnosis must be preceded by adequate genetic counselling and risk assessment of the potential carrier and subsequent support during the diagnostic process.
Ljung
R C
RC
Pediatric Clinic, University of Malmö, University of Lund, Sweden.
D005164:Factor IX / Q000235:genetics; D005169:Factor VIII / Q000235:genetics; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis* / Q000235:genetics; D005787:Gene Frequency; D006580:Genetic Carrier Screening; D005817:Genetic Counseling; D008040:Genetic Linkage; D005865:Gestational Age; D006467:Hemophilia A / Q000175:diagnosis* / Q000235:genetics; D002836:Hemophilia B / Q000175:diagnosis / Q000235:genetics; D006801:Humans; D008297:Male; D009154:Mutation; D010375:Pedigree; D010641:Phenotype; D011110:Polymorphism, Genetic; D011247:Pregnancy; D011296:Prenatal Diagnosis; D018570:Risk Assessment
D005169:Factor VIII; D005164:Factor IX