ARUP's Laboratory Test Directory

Cystic Fibrosis (CFTR) Deletion/Duplication : 0051642
[ image for: Patient History For Cystic Fibrosis (CF) Testing]
Patient History For Cystic Fibrosis (CF) Testing
  


Mnemonic: CFTRDELDUP

Ordering Recommendation: Diagnostic testing for cystic fibrosis. Carrier screening for cystic fibrosis.
Methodology: Multiplex Ligation-dependent Probe Amplification
Performed: Varies
Reported: Within 14 days
Specimen Required: 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.

Remarks: Patient History Form is available on the ARUP Web site or by contacting ARUP Client Services at (800) 522-2787.

Stability (collection to initiation of testing): Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable

Interpretive Data: Background Information for Cystic Fibrosis Deletion and Duplication:
Characteristics:
Chronic sino-pulmonary disease, gastrointestinal malabsorption/pancreatic insufficiency, and obstructive azoospermia.
Background Information for Cystic Fibrosis (CFTR) Deletion/Duplication:
Characteristics:
Chronic sino-pulmonary disease, gastrointestinal malabsorption/pancreatic insufficiency, and obstructive azoospermia.
Incidence:
1 in 3000 Caucasians or Ashkenazi Jewish, 1 in 8000 Hispanics, 1 in 15,000 African-Americans, 1 in 32,000 Asians.
Inheritance:
Autosomal recessive.
Penetrance:
High for severe mutations, variable for mild mutations.
Cause:
Two deleterious CFTR mutations on different chromosomes. Two severe mutations result in classical symptoms of cystic fibrosis, while one severe and one mild mutation results in atypical symptoms.
Mutations Detected:
Large gene rearrangements (deletions and duplications).
Clinical Sensitivity:
Approximately 1-2% of CFTR mutations are large deletions or duplications.
Method:
Multiplex Ligation-dependent Probe Amplification (MLPA) to detect large CFTR coding region deletions/duplications.
Analytical sensitivity and specificity:
90% and 98%, respectively.
Test Limitations:
Deletion/duplication breakpoints will not be determined. CFTR single base pair substitutions, small deletions/duplications, and deep intronic and promoter mutations will not be detected. Mutations within the primer/probe regions could affect the analytical sensitivity of this assay.



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
CPT Code(s): 81222
Cross References: CFTR MLPA (Cystic Fibrosis (CFTR) Deletion/Duplication)