2008 Non-Invasive testing of gene expressions using cell-free RNA increases the chemotherapy target information generated from cell-free DNA testing

2015 ◽  
Vol 51 ◽  
pp. S330
Author(s):  
K. Danenberg ◽  
H.J. Lenz ◽  
J. Usher ◽  
W. Zhang ◽  
R. El-khoueiry ◽  
...  
Keyword(s):  
Dna Testing ◽  
Target Information ◽  
Gene Expressions ◽  
Cell Free Dna ◽  
Non Invasive ◽  
Free Dna

scholarly journals Low Fetal Fraction of Cell-free DNA Identified by Non-invasive Prenatal DNA Testing: Possible Causes, Clinical Significance, and Tactics

Doctor Ru ◽  
2020 ◽  
Vol 19 (8) ◽  
pp. 49-54
Author(s):  
E.V. Kudryavtseva ◽  
◽  
V.V. Kovalev ◽  
I.I. Baranov ◽  
I.V. Kanivets ◽  
...  
Keyword(s):  
Body Weight ◽  
Prenatal Diagnosis ◽  
Trisomy 18 ◽  
Dna Testing ◽  
Cell Free Dna ◽  
Non Invasive ◽  
Monosomy X ◽  
Free Dna ◽  
Repeat Procedure ◽  
Fetal Fraction

Study Objective: To compare the rates of fetal chromosomal abnormalities (CA) detected during initial non-invasive prenatal DNA testing (NIPT) with the rates of CA found through repeat NIPT in patients with low fetal fraction or low quality of cell-free embryonic DNA. Study Design: This was a retrospective cohort study. Materials and Methods: Twenty-one thousand forty-two women who underwent NIPT in Russia between 2013 and 2018 were included in the study. The main group comprised 1,025 of the 1,044 patients with uninformative results (low fetal fraction result, making it impossible to assess the risk of CA), who consented to repeat NIPT. The control group was made up of 19,998 women who had informative results of initial NIPT. The exclusion group comprised women with low fetal fraction who declined repeat screening. The study method was targeted NIPT. Blood samples were taken from a vein and centrifuged to obtain plasma. Fetal cell-free DNA was analyzed by next-generation sequencing (NGS), a method patented by Natera for sequencing single nucleotide polymorphisms. Study Results: Initial NIPT was uninformative in 1,044 (5%) of the patients and repeat procedure yielded informative results in 821 (80.1%) out of 1,025 patients. Among the patients with informative results from the initial study, the rate of chromosomal aneuploidies was 2.4%. In the group of women with informative results from the repeat procedure, fetal CA were detected in 27 (3.3%) cases. In the subgroup of women with informative results only after a third NIPT, the prevalence of CA was 9.3% (seven out of 75 cases). The study showed that in women carrying fetuses with trisomy 18 or 13 or monosomy X, mean fetal fraction in the first trimester was significantly lower than normal. In the second trimester, significantly lower than normal fetal fraction was observed in women carrying fetuses with trisomy 18 or monosomy X. There was a statistically significant difference in fetal fraction levels between patients with body weight <50 kg and those with body weight 80-89 kg or above (р<0.05). Conclusion: The probability of detecting CA by repeat NIPT is significantly higher than in an initial procedure. If initial testing is not informative, it should be repeated. If the second procedure also fails to yield informative results, invasive prenatal diagnosis should be considered. Fetal fraction levels are lower in heavier women. Thus, other methods of prenatal diagnosis should be recommended for overweight and obese women. Keywords: non-invasive prenatal DNA testing, fetal fraction, prenatal diagnosis, Down syndrome.

scholarly journals Quadruple Screening in the Age of Cell-Free DNA: What are We Losing?

OBM Genetics ◽  
2021 ◽  
Vol 05 (03) ◽  
pp. 1-1
Author(s):  
Alison Schmidt ◽  
◽  
Anthony Shanks ◽  
Keyword(s):  
Prenatal Screening ◽  
Screening Tool ◽  
Review Article ◽  
Second Trimester ◽  
Dna Testing ◽  
Cell Free Dna ◽  
Non Invasive ◽  
Free Dna ◽  
Adverse Pregnancy ◽  
Fetal Aneuploidies

Cell-free DNA has emerged as the most reliable, non-invasive prenatal screening tool for fetal aneuploidies. It has come to replace the previously widely used quadruple screen offered in the second trimester of pregnancy. This change comes with improved detection for aneuploidy but also presents potential gaps in prenatal diagnosis including detection of open fetal defects and emerging data on prediction of adverse pregnancy outcomes. This review article provides a historical summary of the quadruple marker screen and evaluates the intersection of this screen with cell-free DNA. Furthermore, it discusses points to consider as providers trend toward cell-free DNA testing alone and reviews potential options to remedy any disparities.

scholarly journals 670. Rapid, Non-invasive Detection of Invasive Mycoplasma hominis Infection using the Karius Test, A Next-Generation Sequencing Test for Microbial Cell-free DNA in Plasma

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S390-S390
Author(s):  
Priya Edward ◽  
William V La Via ◽  
Mehreen Arshad ◽  
Kiran Gajurel
Keyword(s):  
Next Generation Sequencing ◽  
Case Series ◽  
Mycoplasma Hominis ◽  
Microbial Cell ◽  
Next Generation ◽  
Cell Free Dna ◽  
Non Invasive ◽  
Free Dna ◽  
Hominis Infection ◽  
Generation Sequencing

Abstract Background Mycoplasma hominis is typically associated with genital infections in women and is a rare cause of musculoskeletal infections often in immunocompromised hosts. Diagnosis of invasive Mycoplasma hominis infections are difficult due to challenges in culturing these organisms. Molecular diagnostics require an index of suspicion which may not be present at the time of tissue sampling. Accurate, rapid diagnosis of Mycoplasma hominis infections are important for antibiotic management. Methods Two cases of invasive Mycoplasma hominis infections are presented in which the Karius test (KT) was used to make the diagnosis. The KT is a CLIA certified/CAP-accredited next-generation sequencing (NGS) plasma test that detects microbial cell-free DNA (mcfDNA). After mcfDNA is extracted and NGS performed, human reads are removed and remaining sequences are aligned to a curated database of &gt; 1400 organisms. Organisms present above a statistical threshold are reported. Case review was performed for clinical correlation. Results A young woman with lupus nephritis status post renal transplant developed persistent fever with progressive multifocal culture-negative osteoarticular infection despite empiric ceftriaxone. An adolescent female presented with an ascending pelvic infection progressing to purulent polymicrobial peritonitis (see table) requiring surgical debridement and cefipime, metronidazole and micafungin therapy; her course was complicated by progressive peritonitis/abscesses. Karius testing detected high-levels of Mycoplasma hominis mcfDNA in both cases – at 3251 molecules/microliter (MPM) in the first case and 3914 MPM in the second case. The normal range of Mycoplasma hominis mcfDNA in a cohort of 684 normal adults is 0 MPM. The patients rapidly improved with atypical coverage with doxycycline and levofloxaxin. Clinical findings in 2 patients with M. hominis infection detected by the Karius Test Conclusion Open-ended, plasma-based NGS for mcfDNA provides a rapid, non-invasive method to diagnose invasive Mycoplasma hominis infection. This case series highlights the potential to diagnose infections caused by fastidious pathogens to better inform antimicrobial therapy and achieve favorable outcomes. Disclosures William V. La Via, MD, Karius (Employee)

Is there still a rationale for non-invasive PGT-A by analysis of cell-free DNA released by human embryos into culture medium?

2021 ◽  
Vol 36 (5) ◽  
pp. 1186-1190
Author(s):  
Raoul Orvieto ◽  
Adva Aizer ◽  
Norbert Gleicher
Keyword(s):  
Culture Media ◽  
Chromosomal Rearrangements ◽  
Primary Source ◽  
Normal Pregnancy ◽  
Early Embryo ◽  
Human Embryos ◽  
Cell Debris ◽  
Cell Free Dna ◽  
Non Invasive ◽  
Free Dna

Abstract Human embryos utilise an array of processes to eliminate the very high prevalence of aneuploid cells in early embryo stages. Human embryo self-correction was recently demonstrated by their ability to eliminate/expel abnormal blastomeres as cell debris/fragments. A whole genome amplification study has demonstrated that 63.6% of blastocysts expelled cell debris with abnormal chromosomal rearrangements. Moreover, 55.5% of euploid blastocysts expel aneuploid debris, strongly suggesting that the primary source of cell free DNA in culture media is expelled aneuploid blastomeres and/or their fragments. Such a substantial ability to self-correct downstream from the blastocyststage, therefore, renders any chromosomal diagnosis at the blastocyststage potentially useless, and this, unfortunately, also must particularly include non-invasive PGT-A based on cell-free DNA in spent medium. High rates of false-positive diagnoses of human embryos often lead to non-use and/or disposal of embryos with entirely normal pregnancy potential. Before adopting yet another round of unvalidated PGT-A as a routine adjunct to IVF, we here present facts that deserve to be considered.

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