title: Non-invasive prenatal detection of trisomy 13 using a single nucleotide polymorphism- and informatics-based approach.
abstract: OBJECTIVE
  To determine how a single nucleotide polymorphism (SNP)- and informatics-based non-invasive prenatal aneuploidy test performs in detecting trisomy 13.
  
  
  METHODS
  Seventeen trisomy 13 and 51 age-matched euploid samples, randomly selected from a larger cohort, were analyzed. Cell-free DNA was isolated from maternal plasma, amplified in a single multiplex polymerase chain reaction assay that interrogated 19,488 SNPs covering chromosomes 13, 18, 21, X, and Y, and sequenced. Analysis and copy number identification involved a Bayesian-based maximum likelihood statistical method that generated chromosome- and sample-specific calculated accuracies.
  
  
  RESULTS
  Of the samples that passed a stringent DNA quality threshold (94.1%), the algorithm correctly identified 15/15 trisomy 13 and 49/49 euploid samples, for 320/320 correct copy number calls.
  
  
  CONCLUSIONS
  This informatics- and SNP-based method accurately detects trisomy 13-affected fetuses non-invasively and with high calculated accuracy.
authors.affiliation: Department of Research and Development, Natera Inc., San Carlos, California, United States of America.
authors.forename: Megan P
authors.initials: MP
authors.lastname: Hall
authors.affiliation: Department of Research and Development, Natera Inc., San Carlos, California, United States of America.
authors.forename: Matthew
authors.initials: M
authors.lastname: Hill
authors.affiliation: Department of Research and Development, Natera Inc., San Carlos, California, United States of America.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Zimmermann
authors.affiliation: Department of Research and Development, Natera Inc., San Carlos, California, United States of America.
authors.forename: Styrmir
authors.initials: S
authors.lastname: Sigurjonsson
authors.affiliation: Department of Genetic Counseling, Natera Inc., San Carlos, California, United States of America.
authors.forename: Margaret
authors.initials: M
authors.lastname: Westemeyer
authors.affiliation: Department of Genetic Counseling, Natera Inc., San Carlos, California, United States of America.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Saucier
authors.affiliation: Department of Genetic Counseling, Natera Inc., San Carlos, California, United States of America.
authors.forename: Zachary
authors.initials: Z
authors.lastname: Demko
authors.affiliation: Department of Research and Development, Natera Inc., San Carlos, California, United States of America.
authors.forename: Matthew
authors.initials: M
authors.lastname: Rabinowitz
mesh_terms: D000465:Algorithms; D016022:Case-Control Studies; D025063:Chromosome Disorders / Q000175:diagnosis* / Q000235:genetics; D002882:Chromosomes, Human, Pair 13 / Q000235:genetics; D019295:Computational Biology; D005260:Female; D005820:Genetic Testing / Q000379:methods*; D006801:Humans; D020641:Polymorphism, Single Nucleotide; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D014314:Trisomy / Q000175:diagnosis* / Q000235:genetics; D000073839:Trisomy 13 Syndrome