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Objective: Non-invasive prenatal testing (NIPT) based on fetal cells in maternal blood has the advantage over NIPT based on circulating cell-free fetal DNA in that there is no contamination with maternal DNA. This will most likely result in better detection of chromosomal aberrations including subchromosomal defects. The objective of this study was to test whether fetal cells enriched from maternal blood can be used for cell-based NIPT., Methods: We present a method for enriching fetal cells from maternal blood, subsequent amplification of the fetal genome and detection of chromosomal and subchromosomal variations in the genome., Results: An average of 12.8 fetal cells from 30 mL of maternal blood were recovered using our method. Subsequently, whole genome amplification on fetal cells resulted in amplified fetal DNA in amounts and quality high enough to generate array comparative genomic hybridization as well as next-generation sequencing profiles. From one to two fetal cells, we were able to demonstrate copy number differences of whole chromosomes (21, X-, and Y) as well as subchromosomal aberrations (ring X)., Conclusion: Intact fetal cells can be isolated from every maternal blood sample. Amplified DNA from isolated fetal cells enabled genetic analysis by array comparative genomic hybridization and next-generation sequencing. © 2016 John Wiley & Sons, Ltd., (© 2016 John Wiley & Sons, Ltd.)

Objective: The goal was to develop methods for detection of chromosomal and subchromosomal abnormalities in fetal cells in the mother's circulation at 10-16 weeks' gestation using analysis by array comparative genomic hybridization (CGH) and/or next-generation sequencing (NGS)., Method: Nucleated cells from 30 mL of blood collected at 10-16 weeks' gestation were separated from red cells by density fractionation and then immunostained to identify cytokeratin positive and CD45 negative trophoblasts. Individual cells were picked and subjected to whole genome amplification, genotyping, and analysis by array CGH and NGS., Results: Fetal cells were recovered from most samples as documented by Y chromosome PCR, short tandem repeat analysis, array CGH, and NGS including over 30 normal male cells, one 47,XXY cell from an affected fetus, one trisomy 18 cell from an affected fetus, nine cells from a trisomy 21 case, three normal cells and one trisomy 13 cell from a case with confined placental mosaicism, and two chromosome 15 deletion cells from a case known by CVS to have a 2.7 Mb de novo deletion., Conclusion: We believe that this is the first report of using array CGH and NGS whole genome sequencing to detect chromosomal abnormalities in fetal trophoblastic cells from maternal blood. © 2016 The Authors. Prenatal Diagnosis published by John Wiley & Sons, Ltd., (© 2016 The Authors. Prenatal Diagnosis published by John Wiley & Sons, Ltd.)

Objective: Detection of genomic copy number abnormalities in a single cell using array comparative genomic hybridization (CGH) offers a promising non-invasive alternative for prenatal diagnosis. Our objective was to compare three commercially available whole-genome amplification (WGA) kits for their capacity to produce high quality DNA from single cells that is suitable for both molecular genotyping and array CGH., Methods: We examined kit performance on unfixed, fixed and fixed/permeabilized lymphoblastoid cells. Molecular genotyping methods were used to evaluate the fidelity of amplified DNA for genomic profiling, while array CGH was used to assess copy number from single cells harboring trisomy 21, a DiGeorge syndrome deletion, a CMT1A duplication or a MECP2 duplication., Results: Molecular genotyping was achieved from single cells but performance varied between WGA kits. Furthermore, we consistently detected a dosage difference in sex chromosomes for gender mismatched hybridizations and for chromosome 21 in trisomy 21 cells. The 2.5 Mb DiGeorge syndrome deletion was also detected using all three WGA platforms, whereas the 1.3 Mb CMT1A and the 0.6 Mb MECP2 duplications were not consistently detected., Conclusion: These data suggest that single cell molecular genotyping and copy number analysis can be accomplished when WGA conditions are optimized. © 2016 John Wiley & Sons, Ltd., (© 2016 John Wiley & Sons, Ltd.)