title: Evaluation of an Improved Non-invasive Fetal Sex Determination in Haemophilia A Patients.
abstract: BACKGROUND
  Haemophilia A (HA) is the most severe sex-linked bleeding disorder that is characterized with non-controlled and often threatening Haemorrhage. Routine fetal sex determination in early pregnancy with Haemophilia is based on invasive procedures that can be dangerous to the mother and fetus.
  
  
  OBJECTIVE
  The goal of this study is to present an improved assay for the non-invasive fetal sex determination using a Real-Time duplex PCR on the free fetal DNA (ffDNA) obtained from the maternal serum of the HA carriers.
  
  
  METHODS
  Blood samples were eventually collected from 23 pregnant HA carriers between the 8(th) and 12(th) weeks of gestation, and after amplification by duplex-PCR of the single copy of Y chromosome-specific sequence (SRY), the product was then subjected to Real-Time PCR analysis.
  
  
  RESULTS
  Data were compared with the outcome of chorionic villus sampling (CVS) and indicated that the SRY sequence was detected in 6 of 6 serum samples from male pregnancies and that sequence was absent in 9 samples where the fetus was female. The remaining samples determined without having the CVS positive samples.
  
  
  CONCLUSIONS
  We tried to develop a Real-Time duplex PCR for accurate diagnosis of fetal gender early in the pregnancy of HA carriers. This study has brought up two remarkable points, the first is the method's improvement with high specificity in sex determination, especially in screening of prenatal sex-linked disorders in male gender and the second is that fresh serum samples would be a good source for this purpose, advocated by similar studies carried out in this regard.
authors.affiliation: Faculty, Department of Clinical Biochemistry, Faculty of Medical Sciences, Tarbiat Modares University , Tehran, Iran .
authors.forename: Narmin
authors.initials: N
authors.lastname: Mokari-Zadeh
authors.affiliation: Faculty, Department of Clinical Biochemistry, Faculty of Medical Sciences, Tarbiat Modares University , Tehran, Iran .
authors.forename: Seyed Alireza
authors.initials: SA
authors.lastname: Mesbah-Namin
keywords: Cell-free fetal DNA; Congenital bleeding disorders; Maternal serum