title: Fetal DNA detection in maternal plasma throughout gestation.
abstract: The presence of fetal DNA in maternal plasma may represent a source of genetic material which can be obtained noninvasively. We wanted to assess whether fetal DNA is detectable in all pregnant women, to define the range and distribution of fetal DNA concentration at different gestational ages, to identify the optimal period to obtain a maternal blood sample yielding an adequate amount of fetal DNA for prenatal diagnosis, and to evaluate accuracy and predictive values of this approach. This information is crucial to develop safe and reliable non-invasive genetic testing in early pregnancy and monitoring of pregnancy complications in late gestation. Fetal DNA quantification in maternal plasma was carried out by real-time PCR on the SRY gene in male-bearing pregnancies to distinguish between maternal and fetal DNA. A cohort of 1,837 pregnant women was investigated. Fetal DNA could be detected from the sixth week and could be retrieved at any gestational week. No false-positive results were obtained in 163 women with previous embryo loss or previous male babies. Fetal DNA analysis performed blindly on a subset of 464 women displayed 99.4, 97.8 and 100% accuracy in fetal gender determination during the first, second, and third trimester of pregnancy, respectively. No SRY amplification was obtained in seven out of the 246 (2.8%) male-bearing pregnancies. Fetal DNA from maternal plasma seems to be an adequate and reliable source of genetic material for a noninvasive prenatal diagnostic approach.
authors.affiliation: Unit of Genomics for Diagnosis of Human Pathologies, IRCCS H. San Raffaele, Via Olgettina 58, 20132 Milan, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Galbiati
authors.forename: Maddalena
authors.initials: M
authors.lastname: Smid
authors.forename: Dania
authors.initials: D
authors.lastname: Gambini
authors.forename: Augusto
authors.initials: A
authors.lastname: Ferrari
authors.forename: Gabriella
authors.initials: G
authors.lastname: Restagno
authors.forename: Elsa
authors.initials: E
authors.lastname: Viora
authors.forename: Mario
authors.initials: M
authors.lastname: Campogrande
authors.forename: Simona
authors.initials: S
authors.lastname: Bastonero
authors.forename: Marco
authors.initials: M
authors.lastname: Pagliano
authors.forename: Stefano
authors.initials: S
authors.lastname: Calza
authors.forename: Maurizio
authors.initials: M
authors.lastname: Ferrari
authors.forename: Laura
authors.initials: L
authors.lastname: Cremonesi
mesh_terms: D015331:Cohort Studies; D004247:DNA / Q000097:blood*; D005260:Female; D005333:Fetus / Q000502:physiology; D024282:Genes, sry / Q000235:genetics; D005865:Gestational Age; D006801:Humans; D008297:Male; D008431:Maternal-Fetal Exchange / Q000502:physiology; D011247:Pregnancy / Q000097:blood*; D011264:Pregnancy Trimesters / Q000097:blood*; D011296:Prenatal Diagnosis / Q000379:methods; D012732:Sex Determination Analysis / Q000379:methods
chemical_list: D004247:DNA