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Quest Diagnostics

GDSP cfDNA Panela

Available through the California Prenatal Screening Program

Important prenatal screening for all pregnant Californians

 

  • An adapted version of our QNatal® 
    Advanced offering
  • A noninvasive prenatal cell-free
    DNA (cfDNA) screen
  • Can be ordered as early as 10
    weeks gestation
  • Utilizes next-generation sequencing
    (NGS) technology and advanced bioinformatics
    for high sensitivity and specificity*
  • Low no-call rate1
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The California Prenatal Screening (PNS) Program is a comprehensive public health service that makes prenatal screening available to all pregnant individuals in the state who want it. The GDSP cfDNA Panel is available as part of this program.

 

The GDSP cfDNA Panel provides the biological sex (male or female) and screens for:

 

Trisomies:

Trisomy 21 - Down syndrome

Trisomy 18 - Edwards syndrome

Trisomy 13 - Patau syndrome

 

Sex chromosome aneuploidiesb

45,X - Turner syndrome

47,XXY - Klinefelter syndrome

47,XXX - Triple X syndrome

47,XYY - XYY syndrome

 

Fetal sexc

a 

The GDSP (Genetic Disease Screening Program) cfDNA Panel is a cell-free DNA test that screens for increased risk of certain fetal chromosomal abnormalities that may cause birth defects, including trisomy 21 (Down Syndrome), trisomy 18, trisomy 13, and certain sex chromosomal abnormalities (i.e., 45,X, 47,XXY, 47,XXX, and 47,XYY). It can also screen for fetal sex, if elected. The GDSP cfDNA Panel is a screening test, not a diagnostic test, and therefore all positive (i.e., increased risk) results should be followed by genetic counseling and further diagnostic testing and procedures, when clinically indicated. This test does not assess the risk of fetal anomalies such as neural tube defects or ventral wall defects. The GDSP cfDNA Panel is not recommended before 10 weeks gestation due to a significantly increased risk of a failed result. Pregnancy management decisions should not be based on the results of a cfDNA test alone. As with any test, there may be false positives or false negatives. The positive predictive value of the screening test varies by genetic marker, and may be lower for rare conditions. Performance data for the GDSP cfDNA Panel may be obtained by contacting Quest Diagnostics at 1.866.GENE.INFO (1.866.436.3463). The GDSP cfDNA Panel is a laboratory-developed test that has been developed and validated pursuant to the Clinical Laboratory Improvements Amendments of 1988 (CLIA), and as such, has not been reviewed by FDA.
 
b 

Will be reported as additional finding when detected.
 
c 

Can opt out of receiving results for fetal sex.

Comprehensive insights from Quest Diagnostics®—
a leader in genetic testing

Quest Diagnostics has over 30 years of experience in providing prenatal screening and diagnostic testing to help you manage your patients’ care more effectively. We offer more than 900 genetic tests using some of the newest technologies available today.


GDSP cfDNA Panel - Strong performance

High sensitivity and specificity during verification/validation testing and in the real world*

Download our brochure

Verification/validation study

Prior to launch, the GDSP cDNA Panel technology was verified and validated in a study of 2,752 pregnant women, showing high sensitivity and specificity.2

Screen Sensitivity Specificity
Singletons (n=2,637)
90 of 90 trisomy 21 ›99.9% ›99.9%
30 of 30 trisomy 18 ›99.9% ›99.9%
21 of 21 trisomy 13 ›99.9% ›99.9%
1 of 1 sex aneuploidies  ›99.9% ›99.9%
371 of 372 fetal sex ›99.7% accuracy  
Twins (n=115)
10 of 10 trisomy 21 ›99.9% ›99.9%
4 of 4 trisomy 18 ›99.9% ›99.9%
1 of 1 trisomy 13 ›99.9% ›99.9%

Real world data

Study shows strong positive predictive value (PPV) in real world ~70,000 unique pregnancies1
 

Chromosome abnormality
Trisomy 21
Trisomy 18
Trisomy 13
Sex chromosome aneuploidy
GDSP cfDNA Panel PPV
98.1%
88.2%
59.3%
69%

Easily order the GDSP cfDNA Panel through the CalGenetic Portal

  1. Visit https://calgenetic.cdph.ca.gov
  2. Select "Quest Dx (GDSP cfDNA Panel) CL: 94804005"
  3. Instructions will be provided for printing the California PNS Program Consent and cfDNA Order Confirmation
  4. Obtain the patient’s signature and date on the consent form
  5. Copy the patient’s insurance card, affixing patient-specific barcodes
  6. Draw the sample and send to Quest Diagnostics using Quest courier pickup

Please note steps 5 and 6 only apply if the specimen is drawn on-site rather than utilizing a Quest Diagnostics Patient Service Center.

Test name:
Quest Dx GDSP cfDNA Panel

Specimen requirements:
• 10mL whole blood collected in 1 Streck tube at 10 weeks of gestation or later
• Store specimens at room temperature; do not refrigerate or freeze

Screening test results will be provided through the CalGenetic Portal.

Results are typically available in 7-10 days. If you have any questions about the status of your order, please reach out to the California Department of Public Health Clinical Care Coordinators.

For more information on the California PNS Program, visit https://www.cdph.ca.gov/​Programs/​CFH/​DGDS/​Pages/pns/​healthcareprovider.aspx

Quest supports your patients and your practice 
throughout the pregnancy journey

Additional screening and diagnostic tests including for cystic fibrosis, spinal muscular atrophy, fragile X, and more, can be ordered directly from Quest Diagnostics via your Quanum account, interfaced EHR, or Quest Diagnostics paper requisition. For a full list of tests, please visit our Test Directory.

Convenient blood draws

Quest Diagnostics has more than 400 Patient Service Centers (PSCs) in California, giving your patients the accessibility they need.

Access to genetic counselors

Quest has a team of genetic counselors ready to answer your questions. To reach a genetic counselor, call 1.866.GENE.INFO (1.866.436.3463) Monday through Friday from 5:30 AM to 5:30 PM PT.

A full-service genetics laboratory

We offer a broad range of testing options that includes cytogenetic testing on amniocentesis and CVS specimens. If your patients need follow-up diagnostic testing, you can feel comfortable knowing the results will be analyzed by the same laboratory.

A focus on innovation

With peer-reviewed publications and research studies, Quest continues to innovate and help shape women’s healthcare.

For more information, contact your Quest Diagnostics sales representative, or call 1.866.GENE.INFO (1.866.436.3463)

  1. Guy C, Haji-Sheikhi F, Rowland CM, et al. Prenatal cell-free DNA screening for fetal aneuploidy in pregnant women at average or high risk: Results from a large US clinical laboratory. Mol Genet Genomic Med. 2019;7(3):e545. doi:10.1002/mgg3.545 (finding a no-call rate of 3.5%; several authors affiliated with Quest Diagnostics); “No call rate” refers to the percentage of samples for which results could not be reported.
  2. Anderson B et al. An automated, non-invasive prenatal screening assay (NIPS) for trisomy 21,18,13 in singleton and twin gestations [FIGO abstract FCS79.3.]. Int J Gynaecol Obstet. 2015;131(Suppl 5):E264. The study summarized in this abstract was used to validate QNatal Advanced prior to launch, and QNatal Advanced uses the same technology as the GDSP cfDNA Panel to screen for trisomies. Subsequent validation data is available upon request at 1.866.GENE.INFO (1.866.436.3463) Monday-Friday from 8:30 AM to 8:00 PM ET.

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For assistance with questions about the testing process or locations, call 1.866.MYQUEST (1.866.697.8378)

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Quest® is the brand name used for services offered by Quest Diagnostics Incorporated and its affiliated companies. Quest Diagnostics Incorporated and certain affiliates are CLIA-certified laboratories that provide HIPAA-covered services.  Other affiliates operated under the Quest® brand, such as Quest Consumer Inc., do not provide HIPAA-covered services. 

 

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