Validation of a SNP-based non-invasive prenatal test to detect the fetal 22q11.2 deletion in maternal plasma samples

• Published in: PloS one Vol. 13; no. 2; p. e0193476
• Main Authors: Ravi, Harini, McNeill, Gabriel, Goel, Shruti, Meltzer, Steven D, Hunkapiller, Nathan, Ryan, Allison, Levy, Brynn, Demko, Zachary P
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 23.02.2018; Public Library of Science (PLoS)
• Subjects: Abnormalities; Adult; Amniocentesis; Analysis; Aneuploidy; Assaying; Biology and Life Sciences; Children & youth; Chromosome Deletion; Chromosomes; Chromosomes, Human, Pair 22; Clonal deletion; Congenital diseases; Deoxyribonucleic acid; DNA; Female; Fetuses; Gene deletion; Genetic aspects; Genetic Testing - methods; Gynecology; Humans; Intermetallic compounds; Laboratories; Medicine and Health Sciences; Mothers; Nickel base alloys; Nickel compounds; Obstetrics; Physiological aspects; Plasma - metabolism; Platinum compounds; Polymorphism, Single Nucleotide; Pregnancy; Prenatal diagnosis; Prenatal Diagnosis - methods; Research and Analysis Methods; Sampling methods; Sensitivity; Single nucleotide polymorphisms; Single-nucleotide polymorphism; Women; United States; New York; United States > US
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0193476

Non-invasive prenatal testing (NIPT) for aneuploidy using cell-free DNA in maternal plasma has been widely adopted. Recently, NIPT coverage has expanded to detect subchromosomal abnormalities including the 22q11.2 deletion. Validation of a SNP-based NIPT for detection of 22q11.2 deletions demonstrating a high sensitivity (97.8%) and specificity (99.75%) has been reported. We sought to further demonstrate the performance of a revised version of the test in a larger set of pregnancy plasma samples. Blood samples from pregnant women (10 with 22q11.2-deletion‒affected fetuses and 390 negative controls) were successfully analyzed using a revised SNP-based NIPT for the 22q11.2 deletion. The sensitivity and specificity of the assay were measured. Sensitivity of the assay was 90% (9/10), and specificity of the assay was 99.74% (389/390), with a corresponding false positive-rate of 0.26%. The data presented in this study add to the growing body of evidence demonstrating the ability of the SNP-based NIPT to detect 22q11.2 deletions with high sensitivity and specificity.