title: Noninvasive prenatal testing of trisomies 21 and 18 by massively parallel sequencing of maternal plasma DNA in twin pregnancies.
abstract: OBJECTIVE
  The objective of this study is to assess the performance of noninvasive prenatal testing for trisomies 21 and 18 on the basis of massively parallel sequencing of cell-free DNA from maternal plasma in twin pregnancies.
  
  
  METHODS
  A double-blind study was performed over 12 months. A total of 189 pregnant women carrying twins were recruited from seven hospitals. Maternal plasma DNA sequencing was performed to detect trisomies 21 and 18. The fetal karyotype was used as gold standard to estimate the sensitivity and specificity of sequencing-based noninvasive prenatal test.
  
  
  RESULTS
  There were nine cases of trisomy 21 and two cases of trisomy 18 confirmed by karyotyping. Plasma DNA sequencing correctly identified nine cases of trisomy 21 and one case of trisomy 18. The discordant case of trisomy 18 was an unusual case of monozygotic twin with discordant fetal karyotype (one normal and the other trisomy 18). The sensitivity and specificity of maternal plasma DNA sequencing for fetal trisomy 21 were both 100% and for fetal trisomy 18 were 50% and 100%, respectively.
  
  
  CONCLUSIONS
  Our study further supported that sequencing-based noninvasive prenatal testing of trisomy 21 in twin pregnancies could be achieved with a high accuracy, which could effectively avoid almost 95% of invasive prenatal diagnosis procedures.
authors.affiliation: Fetal Medicine Center, Department of Obstetrics and Gynecology, First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Huang
authors.forename: Jing
authors.initials: J
authors.lastname: Zheng
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.forename: Yangyu
authors.initials: Y
authors.lastname: Zhao
authors.forename: Chunlei
authors.initials: C
authors.lastname: Zhang
authors.forename: Lifu
authors.initials: L
authors.lastname: Liu
authors.forename: Weiwei
authors.initials: W
authors.lastname: Xie
authors.forename: Shuqiong
authors.initials: S
authors.lastname: Shi
authors.forename: Yuan
authors.initials: Y
authors.lastname: Wei
authors.forename: Dongzhu
authors.initials: D
authors.lastname: Lei
authors.forename: Chenming
authors.initials: C
authors.lastname: Xu
authors.forename: Qichang
authors.initials: Q
authors.lastname: Wu
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Guo
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Shi
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.forename: Qiufang
authors.initials: Q
authors.lastname: Liu
authors.forename: Ya
authors.initials: Y
authors.lastname: Gao
authors.forename: Fuman
authors.initials: F
authors.lastname: Jiang
authors.forename: Hongyun
authors.initials: H
authors.lastname: Zhang
authors.forename: Fengxia
authors.initials: F
authors.lastname: Su
authors.forename: Huijuan
authors.initials: H
authors.lastname: Ge
authors.forename: Xuchao
authors.initials: X
authors.lastname: Li
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Pan
authors.forename: Shengpei
authors.initials: S
authors.lastname: Chen
authors.forename: Fang
authors.initials: F
authors.lastname: Chen
authors.forename: Qun
authors.initials: Q
authors.lastname: Fang
authors.forename: Hui
authors.initials: H
authors.lastname: Jiang
authors.forename: Tze Kin
authors.initials: TK
authors.lastname: Lau
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D002887:Chromosomes, Human, Pair 18; D004247:DNA / Q000032:analysis* / Q000097:blood; D004311:Double-Blind Method; D004314:Down Syndrome / Q000097:blood / Q000175:diagnosis*; D005260:Female; D005333:Fetus / Q000737:chemistry*; D005865:Gestational Age; D059014:High-Throughput Nucleotide Sequencing / Q000379:methods*; D006801:Humans; D059785:Karyotype; D011247:Pregnancy; D059285:Pregnancy, Twin / Q000097:blood*; D011296:Prenatal Diagnosis / Q000379:methods; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA / Q000379:methods*; D014314:Trisomy / Q000175:diagnosis*; D000073842:Trisomy 18 Syndrome; D055815:Young Adult
chemical_list: D004247:DNA