Cystic Fibrosis (CF) Full-gene Carrier Screen

Synonyms

CF full gene sequencing
CF testing
CF carrier testing

Test Details

Turnaround Time

14 - 21 days

In some cases, additional time may be required for confirmatory or reflex tests.

Use

Carrier screening for cystic fibrosis by full gene sequencing and deletion/duplication analysis. Variants of uncertain significance are not included.

Special Instructions

To test fetal specimens, including cordblood, order test code 482389, GeneSeq PLUS, Fetal Analysis

Test Includes

This test includes the following gene: CFTR

Limitations

Technologies used do not detect germline mosaicism and do not rule out the presence of large chromosomal aberrations including rearrangements and gene fusions, or variants in regions or genes not included in this test, or possible inter/intragenic interactions between variants, or repeat expansions. Variant classification and/or interpretation may change over time if more information becomes available. False positive or false negative results may occur for reasons that include: rare genetic variants, sex chromosome abnormalities, pseudogene interference, blood transfusions, bone marrow transplantation, somatic or tissue-specific mosaicism, mislabeled samples, or erroneous representation of family relationships. This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.

Methodology

Next-generation sequencing to identify genetic variants, including small nucleotide variants (SNVs), insertions, deletions, and copy number variants (CNVs).

References

Deignan JL, Astbury C, Cutting GR et al. CFTR variant testing: a technical standard of the American College of Medical Genetics and Genomics (ACMG). Genet Med 22, 1288 (2020). PMID: 32404922

Ong T, Marshall SG, Karczeski BA, et al. Cystic Fibrosis and Congenital Absence of the Vas Deferens. 2001 Mar26 [Updated 2017 Feb 2]. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. PMID: 20301428

Specimen Requirements

Information on collection, storage, and volume

Specimen

Whole blood or PurFlock buccal swab kit or Oragene Dx 500 saliva kit

Volume

4 mL whole blood or PurFlock buccal swab kit or Oragene Dx saliva kit

Minimum Volume

3 mL whole blood or PurFlock buccal swab kit or Oragene Dx saliva kit

Container

Yellow-top (ACD-A) or lavender-top (EDTA) or pink-top (EDTA) or tan-top (EDTA) tubes or PurFlock buccal swab kit or Oragene Dx 500 saliva collection kit

Storage Instructions

Maintain specimen at room temperature or refrigerate at 4┬░C. Do not freeze.

Causes for Rejection

Frozen or hemolyzed specimen; quantity not sufficient for analysis; improper container

Collection

Standard phlebotomy. Follow PurFlock buccal swab kit or Oragene Dx 500 saliva kit collection instructions. Do not eat, drink, smoke, or chew gum 30 min prior to collection.