title: Droplet digital PCR combined with minisequencing, a new approach to analyze fetal DNA from maternal blood: application to the non-invasive prenatal diagnosis of achondroplasia.
abstract: BACKGROUND
  Achondroplasia is generally detected by abnormal prenatal ultrasound findings in the third trimester of pregnancy and then confirmed by molecular genetic testing of fetal genomic DNA obtained by aspiration of amniotic fluid. This invasive procedure presents a small but significant risk for both the fetus and mother. Therefore, non-invasive procedures using cell-free fetal DNA in maternal plasma have been developed for the detection of the fetal achondroplasia mutations.
  
  
  METHODS
  To determine whether the fetus carries the de novo mis-sense genetic mutation at nucleotide 1138 in FGFR3 gene involved in >99% of achondroplasia cases, we developed two independent methods: digital-droplet PCR combined with minisequencing, which are very sensitive methods allowing detection of rare alleles.
  
  
  RESULTS
  We collected 26 plasmatic samples from women carrying fetus at risk of achondroplasia and diagnosed to date a total of five affected fetuses in maternal blood. The sensitivity and specificity of our test are respectively 100% [95% confidence interval, 56.6-100%] and 100% [95% confidence interval, 84.5-100%].
  
  
  CONCLUSIONS
  This novel, original strategy for non-invasive prenatal diagnosis of achondroplasia is suitable for implementation in routine clinical testing and allows considering extending the applications of these technologies in non-invasive prenatal diagnosis of many other monogenic diseases. © 2016 John Wiley & Sons, Ltd.
authors: Service de Biochimie et Génétique Moléculaire, HUPC Hôpital Cochin, Paris, France.
authors: Lucie
authors: L
authors: Orhant
authors: Maternité Cochin-Port Royal, HUPC Hôpital Cochin, Paris, France.
authors: Olivia
authors: O
authors: Anselem
authors: Service de Génétique Médicale, CHU de Rennes, Rennes, France.
authors: Mélanie
authors: M
authors: Fradin
authors: Service de Biochimie et Génétique Moléculaire, HUPC Hôpital Cochin, Paris, France.
authors: Pierre Hadrien
authors: PH
authors: Becker
authors: Service de Biochimie et Génétique Moléculaire, HUPC Hôpital Cochin, Paris, France.
authors: Caroline
authors: C
authors: Beugnet
authors: Service de Biochimie et Génétique Moléculaire, HUPC Hôpital Cochin, Paris, France.
authors: Nathalie
authors: N
authors: Deburgrave
authors: Service de Biochimie et Génétique Moléculaire, HUPC Hôpital Cochin, Paris, France.
authors: Gilles
authors: G
authors: Tafuri
authors: INSERM, U1016, Institut Cochin, CNRS UMR8104, Université Paris Descartes, Paris, France.
authors: Franck
authors: F
authors: Letourneur
authors: Maternité Cochin-Port Royal, HUPC Hôpital Cochin, Paris, France.
authors: François
authors: F
authors: Goffinet
authors: Laboratoire de Cytogénétique, HUPC Hôpital Cochin, Paris, France.
authors: Laïla
authors: L
authors: Allach El Khattabi
authors: Service de Biochimie et Génétique Moléculaire, HUPC Hôpital Cochin, Paris, France.
authors: France
authors: F
authors: Leturcq
authors: Service de Biochimie et Génétique Moléculaire, HUPC Hôpital Cochin, Paris, France.|INSERM, U1016, Institut Cochin, CNRS UMR8104, Université Paris Descartes, Paris, France.
authors: Thierry
authors: T
authors: Bienvenu
authors: Maternité Cochin-Port Royal, HUPC Hôpital Cochin, Paris, France.
authors: Vassilis
authors: V
authors: Tsatsaris
authors: Service de Biochimie et Génétique Moléculaire, HUPC Hôpital Cochin, Paris, France.|INSERM, U1016, Institut Cochin, CNRS UMR8104, Université Paris Descartes, Paris, France.
authors: Juliette
authors: J
authors: Nectoux
mesh_terms: D000130:Achondroplasia / Q000097:blood / Q000175:diagnosis* / Q000235:genetics; D000465:Algorithms; D016022:Case-Control Studies; D004247:DNA / Q000097:blood* / Q000235:genetics; D005260:Female; D006801:Humans; D062145:Maternal Serum Screening Tests; D020125:Mutation, Missense; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011296:Prenatal Diagnosis; D051498:Receptor, Fibroblast Growth Factor, Type 3 / Q000235:genetics; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA
chemical_list: D004247:DNA; C496365:FGFR3 protein, human; D051498:Receptor, Fibroblast Growth Factor, Type 3