title: Prenatal diagnosis in severe von Willebrand disease families from India using combination of phenotypic and genotypic assays.
abstract: OBJECTIVE
  This study aimed to offer genetic diagnosis to affected type 3 severe von Willebrand disease families.
  
  
  METHODS
  Thirteen families were referred for prenatal diagnosis during the first and second trimesters of pregnancy. Prenatal diagnosis was offered by chorionic villus sampling between 11 and 12 weeks and by cordocentesis between 18 and 19.5 weeks of gestation. Phenotypic analysis included FVIII:C and von Willebrand factor antigen assays. A combination of molecular biological techniques which included PCR-restriction fragment length polymorphism technique using intron 40 variable number tandem repeat (VNTR) markers, conformation sensitive gel electrophoresis, direct DNA sequencing, and multiple ligation probe amplification (MLPA) were used to offer genotyic diagnosis in the remaining families.
  
  
  RESULTS
  Diagnosis was offered by intron 40 VNTR analysis in eight families. In one family, the diagnosis was given by direct mutation detection technique, whereas in another diagnosis was given by MLPA technique as the index case showed the presence of large deletion within von Willebrand factor. In three families, diagnosis was offered by cordocentesis on the basis of phenotypic assays, further confirmed by genotyping.
  
  
  CONCLUSIONS
  Both first and second-trimester prenatal diagnoses could be successfully offered using a combination of phenotypic and genotypic techniques to all severe von Willebrand disease families.
authors.affiliation: National Institute of Immunohaematology (ICMR), KEM Hospital, Parel, Mumbai, 400 012, India.
authors.forename: Priyanka
authors.initials: P
authors.lastname: Kasatkar
authors.forename: Shrimati
authors.initials: S
authors.lastname: Shetty
authors.forename: Kanjaksha
authors.initials: K
authors.lastname: Ghosh
mesh_terms: D000328:Adult; D015193:Chorionic Villi Sampling / Q000379:methods*; D017218:Cordocentesis / Q000379:methods*; D005169:Factor VIII / Q000032:analysis*; D005260:Female; D060005:Genotyping Techniques; D006801:Humans; D007194:India; D018598:Minisatellite Repeats; D010641:Phenotype; D012150:Polymorphism, Restriction Fragment Length; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D017422:Sequence Analysis, DNA; D056729:von Willebrand Disease, Type 3 / Q000097:blood / Q000175:diagnosis* / Q000235:genetics; D014841:von Willebrand Factor / Q000032:analysis* / Q000235:genetics
chemical_list: D014841:von Willebrand Factor; D005169:Factor VIII