Cystic Fibrosis (CFTR) Sequencing with Reflex to Deletion/Duplication
0051640
 
Ordering Recommendation
Diagnostic testing for cystic fibrosis.
Mnemonic
CFTR FGA
Methodology
Polymerase Chain Reaction/Sequencing/Multiplex Ligation-dependent Probe Amplification
Performed
Varies
Reported
Within 35 days
New York DOH Approval Status
Specimens from New York clients will be sent out to a New York DOH approved laboratory.
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.



Counseling and informed consent are recommended for genetic testing. Consent forms are available online at www.aruplab.com.

See Compliance Statement C: www.aruplab.com/CS
Note
If sequencing identifies less than two pathogenic mutations, then CFTR deletion/duplication will be added. Additional charges apply.
CPT Code(s)
81223. If reflex, add 81222
Components
Component Test Code*Component Chart Name
0051639Cystic Fibrosis (CFTR) Seq, DelDup Int
2001346Cystic Fibrosis (CFTR) Seq, 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, contact interface support at interface.support@aruplab.com.
Cross References