Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Genetic Testing via Mutation Analysis (Qualitative)
This test checks for specific genetic mutations linked to cystic fibrosis (CF), a condition affecting lungs, digestive system, and other organs. It helps determine if you carry mutations associated with CF.
["Identifying CFTR mutations can guide diagnosis, treatment planning, and family counseling for inherited conditions."]
Key facts at a glance
- LOINC
- 38455-2
- Short code
- CFTR621
- Synonyms
- CFTR c.621+1G>T Bld/T Ql
- Category
- chemistry
- Sample
- whole-blood
- Container
- EDTA tube (lavender-top) for whole blood; sterile container for tissue specimens. DNA extracted from submitted specimen is used for analysis.
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- molgen
- CPT
- 81223
- SNOMED
- 5304003
- Specimen volume
- 3-5 mL of whole blood in EDTA tube; minimum 1 mL. For tissue: adequate sample size as determined by submitting facility (typically a small biopsy specimen).
- Stability
- Whole blood: stable at room temperature (20-25°C) for up to 7 days, or refrigerated at 2-8°C for up to 14 days. Do not freeze whole blood. Extracted DNA: stable at 2-8°C for up to 30 days, or at -20°C for long-term storage. Tissue: stable in appropriate transport medium per laboratory protocol.
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 168–720 hours
- Order
- routine
What This Test Measures
The test analyzes DNA from a blood sample to detect known mutations in the CFTR gene. Certain mutations are strongly linked to cystic fibrosis, while others may indicate a higher risk or different genetic variations.
Why It’s Ordered
Your healthcare provider may recommend this test if you have symptoms of CF (like chronic lung infections, digestive issues, or salt loss), a family history of CF, or if you’re considering pregnancy and have a partner with a known CF mutation.
Sample Collection and Process
A blood sample is drawn from your arm. The DNA is extracted from your white blood cells and analyzed for specific mutations using advanced genetic techniques.
Test Results and Interpretation
Results are qualitative—either confirming the presence or absence of specific mutations. A positive result for known CF mutations may confirm a diagnosis, while negative results mean those mutations are not detected in your DNA.
Reference range
Negative (mutation not detected). This test is qualitative; results are reported as either Detected (Positive) or Not Detected (Negative) for the CFTR c.621+1G>T variant.N/A
No special preparation or fasting is required. Patients should provide informed consent prior to genetic testing. A detailed family history and clinical indication for testing should be documented. Genetic counseling is recommended before and after testing.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
CFTR Gene Mutation Test
Frequently asked questions
What does a positive result mean?
Can this test detect all CF mutations?
How long does it take to get results?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy