title: Trophoblast Retrieval and Isolation From the Cervix for Noninvasive, First Trimester, Fetal Gender Determination in a Carrier of Congenital Adrenal Hyperplasia.
abstract: Congenital adrenal hyperplasia (CAH) is an autosomal recessive defect in cortisol biosynthesis that elevates fetal androgen levels to cause genital ambiguity and external genital masculinization in newborn females. Introducing dexamethasone in utero by 7 weeks gestation precludes virilization of affected females. However, identification of a male fetus prior to week 7 could avert the necessity of steroid treatment in half of pregnancies at risk of CAH. We recently introduced trophoblast retrieval and isolation from the cervix (TRIC), an approach that noninvasively isolate homogeneous trophoblast cells from pregnant women as early as 5 weeks gestation, using a Papanicolaou test. Here, we have used TRIC to correctly identify male fetal DNA when both parents were carriers of the mutation that produces CAH and previously produced an affected child. Trophoblast cells (1400) obtained by TRIC were assessed using immunocytochemistry with an antibody against the trophoblast-specific β subunit of human chorionic gonadotropin, which labeled 100% (17 of 17) of isolated cells, while none of the excluded maternal cervical cells were labeled. The isolated cells were examined by fluorescent in situ hybridization for chromosomes 18, X, and Y at a clinical cytogenetics laboratory, demonstrating 100% (18 of 18) of cells to be diploid 18/XY. Aliquots of DNA obtained from the isolated cells assayed for SRY and RNASEH genes by TaqMan assays confirmed a male fetus. This case study demonstrates the utility of TRIC to accurately identify fetal gender as a means of reducing the need for prophylactic administration of exogenous steroids in pregnancies at risk of CAH.
authors.affiliation: Department of Obstetrics & Gynecology, Wayne State University, Detroit, MI, USA.
authors.forename: Alan D
authors.initials: AD
authors.lastname: Bolnick
authors.affiliation: Department of Obstetrics & Gynecology, Wayne State University, Detroit, MI, USA Department of Physiology, Wayne State University, Detroit, MI, USA.
authors.forename: Rani
authors.initials: R
authors.lastname: Fritz
authors.affiliation: Department of Obstetrics & Gynecology, Wayne State University, Detroit, MI, USA Department of Physiology, Wayne State University, Detroit, MI, USA.
authors.forename: Chandni
authors.initials: C
authors.lastname: Jain
authors.affiliation: Department of Obstetrics & Gynecology, Wayne State University, Detroit, MI, USA Department of Physiology, Wayne State University, Detroit, MI, USA.
authors.forename: Leena
authors.initials: L
authors.lastname: Kadam
authors.affiliation: Department of Obstetrics & Gynecology, Wayne State University, Detroit, MI, USA.
authors.forename: Jay M
authors.initials: JM
authors.lastname: Bolnick
authors.affiliation: Department of Obstetrics & Gynecology, Wayne State University, Detroit, MI, USA.
authors.forename: Brian A
authors.initials: BA
authors.lastname: Kilburn
authors.affiliation: Department of Obstetrics & Gynecology, Wayne State University, Detroit, MI, USA.
authors.forename: Manvinder
authors.initials: M
authors.lastname: Singh
authors.affiliation: Department of Obstetrics and Gynecology, Georgia Regents University, Augusta, GA, USA.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Diamond
authors.affiliation: Department of Obstetrics & Gynecology, Wayne State University, Detroit, MI, USA.
authors.forename: Sascha
authors.initials: S
authors.lastname: Drewlo
authors.affiliation: Department of Obstetrics & Gynecology, Wayne State University, Detroit, MI, USA Department of Anatomy & Cell Biology, Wayne State University School of Medicine, Detroit, MI, USA Program in Reproductive and Adult Endocrinology, National Institute for Child Health and Human Development, National Institutes of Health, United States Department of Health and Human Services, Bethesda, MD, USA d.armant@wayne.edu.
authors.forename: D Randall
authors.initials: DR
authors.lastname: Armant
mesh_terms: D000312:Adrenal Hyperplasia, Congenital / Q000150:complications / Q000235:genetics*; D002584:Cervix Uteri / Q000166:cytology*; D002887:Chromosomes, Human, Pair 18 / Q000235:genetics; D041321:Chromosomes, Human, X / Q000235:genetics; D041322:Chromosomes, Human, Y / Q000235:genetics; D005260:Female; D005820:Genetic Testing; D005838:Genotype; D006801:Humans; D008297:Male; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011296:Prenatal Diagnosis / Q000379:methods*; D012732:Sex Determination Analysis / Q000379:methods*; D014327:Trophoblasts / Q000378:metabolism*
keywords: 21-hydroxylase; congenital adrenal hyperplasia; fluorescence in situ hybridization; placenta; prenatal genetic diagnosis; steroids; trophoblast