title: Detection of aneuploidy from single fetal nucleated red blood cells using whole genome sequencing.
abstract: OBJECTIVE
  The objective of the study was to detect aneuploidy in single fetal nucleated red blood cells (FNRBCs) from placental villi using whole genome amplification (WGA) and next generation sequencing.
  
  
  METHODS
  Three single FNRBCs per sample were manually picked from villi collected from ten women undergoing elective first-trimester termination of pregnancy, and one or two cells were picked from each of four aneuploid chorionic villus samples. Following WGA and addition of adaptor and index sequences, samples were sequenced on the Illumina MiSeq. Leading and trailing 15 bases were trimmed, and reads were aligned to the human reference genome. Z-scores were calculated to determine deviation of the mean of the test from reference samples, with a score of 3 used as the threshold for classification of a particular chromosome as trisomic.
  
  
  RESULTS
  We successfully made correct diagnoses from ten single cells isolated from villi from two cases of trisomy 21 (one case from a single cell and one from two cells), two cases of trisomy 18 (two cells each), and a case of trisomy 15 (three cells).
  
  
  CONCLUSIONS
  With their faithful representation of fetal genome, diagnosis using single FNRBCs provides a definitive result compared with non-invasive prenatal testing using cell-free fetal DNA, and is a safer alternative to invasive amniocentesis.
authors.affiliation: Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228.|Department of Obstetrics and Gynaecology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Hua
authors.affiliation: Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228.
authors.forename: Angela N
authors.initials: AN
authors.lastname: Barrett
authors.affiliation: Cancer Science Institute of Singapore, National University of Singapore, Singapore, S117599.
authors.forename: Tuan Zea
authors.initials: TZ
authors.lastname: Tan
authors.affiliation: Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228.
authors.forename: Zhouwei
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228.
authors.forename: Aniza Puteri
authors.initials: AP
authors.lastname: Mahyuddin
authors.affiliation: Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228.
authors.forename: Sukumar
authors.initials: S
authors.lastname: Ponnusamy
authors.affiliation: Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228.
authors.forename: Jaspal Singh
authors.initials: JS
authors.lastname: Sandhu
authors.affiliation: Department of Laboratory Medicine, Molecular Diagnosis Centre, National University Hospital, Singapore, S119074.
authors.forename: Sherry S Y
authors.initials: SS
authors.lastname: Ho
authors.affiliation: Experimental Fetal Medicine Group, Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228.|Department of Reproductive Medicine, KK Women's and Children's Hospital, Singapore, S229899.
authors.forename: Jerry K Y
authors.initials: JK
authors.lastname: Chan
authors.affiliation: Department of Paediatrics, Yong Loo Lin School of Medicine, National University Hospital, National University of Singapore, Singapore, S119074.
authors.forename: Samuel
authors.initials: S
authors.lastname: Chong
authors.affiliation: Department of Obstetrics and Gynaecology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.
authors.forename: Song
authors.initials: S
authors.lastname: Quan
authors.affiliation: Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, S119228.
authors.forename: Mahesh
authors.initials: M
authors.lastname: Choolani
mesh_terms: D015193:Chorionic Villi Sampling; D002884:Chromosomes, Human, Pair 15; D002887:Chromosomes, Human, Pair 18 / Q000235:genetics; D004314:Down Syndrome / Q000175:diagnosis / Q000235:genetics; D004900:Erythroblasts; D005260:Female; D015894:Genome, Human; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D007621:Karyotyping / Q000379:methods; D008297:Male; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D017422:Sequence Analysis, DNA / Q000379:methods*; D014314:Trisomy / Q000175:diagnosis* / Q000235:genetics; D000073842:Trisomy 18 Syndrome