title: Noninvasive fetal sex determination in maternal plasma: a prospective feasibility study.
abstract: OBJECTIVE
  To prospectively validate a protocol for noninvasive fetal sex determination in maternal plasma and demonstrate its applicability to clinical practice.
  
  
  METHODS
  Peripheral blood from 404 pregnant women undergoing prenatal invasive testing was collected from 6 to 23 weeks of gestation. Real-time PCR was performed for the SRY gene and multicopy DYS14 marker sequence located within the TSPY gene by the TaqMan minor groove binder probe assay as a first-line test. Owing to a false-positive result, amplification of repetitive motifs of the DAZ gene region was also tested as a second-line test performed in the last 232 patients enrolled in our series. A diagnostic algorithm was designed using a combination of these three markers. Fetal gender determined by noninvasive prenatal diagnosis (NIPD) was compared with that diagnosed by quantitative fluorescent PCR after invasive testing or ultrasound.
  
  
  RESULTS
  A single false-positive result was obtained in the first 172 pregnancies. Reporting criteria were modified in the subsequent 232 pregnancies, giving an overall sensitivity and specificity of 100% (95% CI 99.8-100%) and 99.5% (95% CI 98.1-100%), respectively. Pregnancy outcome was obtained in all cases, including 221 male-bearing and 183 female-bearing pregnancies.
  
  
  CONCLUSIONS
  NIPD for fetal sex determination in maternal plasma is highly accurate and clinically applicable if robust reporting criteria are applied.
authors.affiliation: Department of Genetics, Hospital Universitario, Madrid, Spain. ffernandez.hdoc@salud.madrid.org
authors.forename: F Javier
authors.initials: FJ
authors.lastname: Fernández-Martínez
authors.forename: Alberto
authors.initials: A
authors.lastname: Galindo
authors.forename: Antonio
authors.initials: A
authors.lastname: Garcia-Burguillo
authors.forename: Carmela
authors.initials: C
authors.lastname: Vargas-Gallego
authors.forename: Nuria
authors.initials: N
authors.lastname: Nogués
authors.forename: Marta
authors.initials: M
authors.lastname: Moreno-García
authors.forename: Ana
authors.initials: A
authors.lastname: Moreno-Izquierdo
mesh_terms: D004247:DNA / Q000097:blood; D000075364:Deleted in Azoospermia 1 Protein; D016189:Dystrophin / Q000235:genetics; D005240:Feasibility Studies; D005260:Female; D005333:Fetus; D040181:Genetic Diseases, X-Linked / Q000175:diagnosis / Q000235:genetics; D005820:Genetic Testing / Q000379:methods*; D006801:Humans; D008297:Male; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D011446:Prospective Studies; D016601:RNA-Binding Proteins / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D012732:Sex Determination Analysis / Q000379:methods*; D051876:Sex-Determining Region Y Protein / Q000235:genetics
chemical_list: C095668:DAZ1 protein, human; D000075364:Deleted in Azoospermia 1 Protein; D016189:Dystrophin; D016601:RNA-Binding Proteins; D051876:Sex-Determining Region Y Protein; D004247:DNA