UCL  IRIS
Institutional Research Information Service
UCL Logo
Please report any queries concerning the funding data grouped in the sections named "Externally Awarded" or "Internally Disbursed" (shown on the profile page) to your Research Finance Administrator. Your can find your Research Finance Administrator at https://www.ucl.ac.uk/finance/research/rs-contacts.php by entering your department
Please report any queries concerning the student data shown on the profile page to:

Email: portico-services@ucl.ac.uk

Help Desk: http://www.ucl.ac.uk/ras/portico/helpdesk
Publication Detail
A simple method to allow for guanine-cytosine amplification error in prenatal DNA screening for trisomy 18
  • Publication Type:
    Journal article
  • Publication Sub Type:
    Journal Article
  • Authors:
    Wald NJ, Bestwick JP, Lau KW, Huttly WJ, Ke W, Cheng R, Old RW
  • Publication date:
    01/09/2019
  • Pagination:
    13, 17
  • Journal:
    Clinica Chimica Acta
  • Volume:
    496
  • Status:
    Published
  • Print ISSN:
    0009-8981
Abstract
Background: A source of error in prenatal screening for trisomies is PCR amplification error associated with guanine-cytosine (GC) content of DNA fragments in maternal plasma. We describe a simple method of allowing for this. Methods: Data from a Reflex DNA screening programme (67 trisomy 18 and 83 unaffected pregnancies) were used to compare the ratio of chromosome 18 DNA fragment counts to chromosome 8 DNA fragment counts (because chromosome 8 has a similar GC content to chromosome 18) with the percentage of chromosome 18 DNA counts using counts from all autosomes in the denominator, with and without an all autosome correction for the GC content of the DNA fragments. Results: A chromosome 18 to 8 ratio of DNA fragment counts was more discriminatory than the percentage of all autosome counts arising from chromosome 18 without, or with an all autosome correction for GC content bias. It achieves a high screening performance, eg. for a 0.25% false-positive rate, a 97% detection rate instead of 49% without a correction for GC content, and 91% with an all autosome correction for GC content. Conclusion: Consideration can be given to using the ratio of chromosome 18 DNA fragment counts to chromosome 8 DNA fragment counts in cell-free DNA prenatal screening for trisomy 18, avoiding the need for more complex methods of making a correction for the GC content currently used.
Publication data is maintained in RPS. Visit https://rps.ucl.ac.uk
 More search options
UCL Researchers
Author
Institute of Health Informatics
University College London - Gower Street - London - WC1E 6BT Tel:+44 (0)20 7679 2000

© UCL 1999–2011

Search by