Cystic Fibrosis (CFTR) Sequencing with Reflex to Deletion/Duplication
0051640
Ordering Recommendation
For individuals suspected to be affected with CF but without 2 mutations detected by CF 32 mutation panel.
Mnemonic
CFTR FGA
Methodology
Polymerase Chain Reaction/Sequencing/Multiplex Ligation-dependent Probe Amplification
Performed
Varies
Reported
Within 35 days  
New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
  
Collect
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).  
Specimen Preparation
Transport 3 mL whole blood. (Min: 2 mL)  
Storage/Transport Temperature
Refrigerated.  
Unacceptable Conditions
  
Remarks
Patient History Form is available on the ARUP Web site or by contacting ARUP Client Services at (800) 522-2787.  
Stability
Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable  
Reference Interval
 
 
Test Number Components Reference Interval
0051110Cystic Fibrosis (CFTR) Sequencing By report
0051642Cystic Fibrosis (CFTR) Deletion/Duplication  
Interpretive Data
Background information for Cystic Fibrosis (CFTR) Sequencing with Reflex to Deletion/Duplication:
Characteristics:
Chronic sino-pulmonary disease, gastrointestinal malabsorption/pancreatic insufficiency, and obstructive azoospermia. Findings are often limited to a single organ system such as isolated pancreatitis, bilateral absence of the vas deferens, nasal polyposis, or bronchiectasis in non-classic cystic fibrosis (CF).
Incidence of Classic CF:
1 in 3,000 Caucasians or Ashkenazi Jewish, 1 in 8,000 Hispanics, 1 in 15,000 African Americans, 1 in 32,000 Asians.
Incidence of Nonclassic CF:
Unknown.
Inheritance:
Autosomal recessive.
Penetrance:
High for severe mutations, variable for mild/moderate mutations.
Cause of Classic CF:
Two deleterious CFTR mutations on opposite chromosomes.
Cause of Nonclassic CF:
Typically one severe and one mild/moderate CFTR mutations on opposite chromosomes.
Mutations Tested:
Base pair substitutions and deletions/duplications within the coding region and intron-exon boundaries; additionally, two deep intronic mutations (3849+10kbC>T and 1811+1.6kbA>G).
Clinical Sensitivity:
99 percent.
Methodology for Sequencing:
Bidirectional sequencing of the entire CFTR coding region, intron-exon boundaries and two deep intronic mutations.
Methodology for Deletion/Duplication:
Multiplex ligation-dependent probe amplification (MLPA) to detect large CFTR coding region deletions /duplications.
Analytical Sensitivity & Specificity for Sequencing:
99 percent.
Analytical Sensitivity & Specificity for MLPA:
98 percent.
Limitations:
Diagnostic errors can occur due to rare sequence variations. Breakpoints for large deletions/duplications will not be determined. Regulatory region and some deep intronic mutations will not be detected.





See Compliance Statement C: www.aruplab.com/CS
Statement C: The performance characteristics of this test were validated by ARUP Laboratories. The U.S. Food and Drug Administration (FDA) has not approved or cleared this test; however, FDA approval or clearance is currently not required for clinical use of this test. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions. ARUP is authorized under Clinical Laboratory Improvement Amendments (CLIA) and by all states to perform high-complexity testing.

Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
 
Note
 If sequencing identifies less than two pathogenic mutations, then CFTR deletion/duplication will be added. Additional charges apply.
CPT Code(s)
81223.  If reflexed, add 81222
Components
Component Test Code*Component Chart NameLOINC
0051639Cystic Fibrosis Seq, w/Rflx DelDup Int 
2001346Cystic Fibrosis Seq, w/Rflx DelDup Spec 
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • sequencing reflex