1
|
Zednikova I, Pazourkova E, Lassakova S, Vesela B, Korabecna M. Detection of cell-free foetal DNA fraction in female-foetus bearing pregnancies using X-chromosomal insertion/deletion polymorphisms examined by digital droplet PCR. Sci Rep 2020; 10:20036. [PMID: 33208834 PMCID: PMC7676229 DOI: 10.1038/s41598-020-77084-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Accepted: 10/23/2020] [Indexed: 12/03/2022] Open
Abstract
In families with X-linked recessive diseases, foetal sex is determined prenatally by detection of Y-chromosomal sequences in cell-free foetal DNA (cffDNA) in maternal plasma. The same procedure is used to confirm the cffDNA presence during non-invasive prenatal RhD incompatibility testing but there are no generally accepted markers for the detection of cffDNA fraction in female-foetus bearing pregnancies. We present a methodology allowing the detection of paternal X-chromosomal alleles on maternal background and the confirmation of female sex of the foetus by positive amplification signals. Using digital droplet PCR (ddPCR) we examined X-chromosomal INDEL (insertion/deletion) polymorphisms: rs2307932, rs16397, rs16637, rs3048996, rs16680 in buccal swabs of 50 females to obtain the population data. For all INDELs, we determined the limits of detection for each ddPCR assay. We examined the cffDNA from 63 pregnant women bearing Y-chromosome negative foetuses. The analysis with this set of INDELs led to informative results in 66.67% of examined female-foetus bearing pregnancies. Although the population data predicted higher informativity (74%) we provided the proof of principle of this methodology. We successfully applied this methodology in prenatal diagnostics in a family with Wiscott-Aldrich syndrome and in pregnancies tested for the risk of RhD incompatibility.
Collapse
Affiliation(s)
- Iveta Zednikova
- Department of Biology and Medical Genetics, First Faculty of Medicine, Charles University, Albertov 4, 128 00, Prague, Czech Republic
- Department of Biology and Medical Genetics, General University Hospital in Prague, Albertov 4, 128 00, Prague, Czech Republic
| | - Eva Pazourkova
- Department of Biology and Medical Genetics, First Faculty of Medicine, Charles University, Albertov 4, 128 00, Prague, Czech Republic
- Department of Biology and Medical Genetics, General University Hospital in Prague, Albertov 4, 128 00, Prague, Czech Republic
- Department of Nephrology, First Faculty of Medicine, Charles University and General University Hospital in Prague, U nemocnice 2, 128 08, Prague, Czech Republic
| | - Sona Lassakova
- Department of Biology and Medical Genetics, First Faculty of Medicine, Charles University, Albertov 4, 128 00, Prague, Czech Republic
| | - Barbora Vesela
- Department of Biology and Medical Genetics, First Faculty of Medicine, Charles University, Albertov 4, 128 00, Prague, Czech Republic
| | - Marie Korabecna
- Department of Biology and Medical Genetics, First Faculty of Medicine, Charles University, Albertov 4, 128 00, Prague, Czech Republic.
- Department of Biology and Medical Genetics, General University Hospital in Prague, Albertov 4, 128 00, Prague, Czech Republic.
| |
Collapse
|