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HelpTest Code LAB3820 ABCD1 Single Gene Analysis
Additional Codes
ABCD1 Pnl
ABCD1 Gene Sequencing & Del/Dup
Clinical System Name
ABCD1 Single Gene Analysis
Synonyms
ABCD1
X-Linked Adrenoleukodystrophy
X-Linked ALD
Description
Sample Requirements
Specimen: Whole Blood
Container(s): Lavender Top/EDTA, Yellow/ACD
Preferred Vol: 5.0 mL
Minimum Vol: 3.0 mL (1.0 mL for small infants)
Alternative Specimen: DNA
Container(s): Sterile Plastic Tube
Preferred Vol: 5 µg -10 µg of purified DNA at a concentration of at least 100 ng/μL
Alternative specimens not recommended.
Processing Instructions
Reject due to: Frozen samples are unacceptable. Hemolysis is unacceptable.
Spin: N
Aliquot: N
Temp: 2 - 8 C
Storage Location: Do not spin. Refrigerate whole blood in CPA refrigerator, Send Outs rack.
Off-site Collection: Do not spin. Send refrigerated.
Stability
| Specimen Type | Temperature | Time |
|---|---|---|
| Whole Blood | Room temp |
3 d |
| Refrigerated | 7 d | |
| Frozen |
Unacceptable |
|
| Extracted DNA | Room temp | 3-4 d |
| Refrigerated | 1 y | |
| Frozen | Indefinitely |
Availability
| STAT | Performed | TAT |
|---|---|---|
| N | Varies | 3 - 5 w |
Performing Laboratory
GeneDx
207 Perry Parkway
Gaithersburg, MD 20877
Phone Number: (301) 519-2100
Department
Department: Send Outs/Genetic
Phone Number: (206) 987-2563
Methodology
Analysis is performed by bi-directional sequencing of the coding regions (exons 1-10) and splice sites of the ABCD1 gene. Concurrently, multiplex ligation-dependent probe amplification (MLPA) is performed to evaluate for a deletion or duplication of most exons in this gene. This test does not include deletion/duplication testing of exon 9. Any variant is confirmed by repeat analysis using sequencing, restriction fragment analysis, qPCR, or other appropriate methods.
The methods used by GeneDx are expected to be greater than 99% sensitive in detecting variants identifiable by sequencing.
Reference Range
Interpretive report provided.
Clinical Utility
Diagnosis/testing.
Three scenarios for suspecting the diagnosis are: (1) positive newborn screening result, which to date is performed in more than half of the United States; (2) a male or female proband with suggestive clinical and laboratory findings; (3) a male not known to have X-ALD ascertained and diagnosed via family screening. The diagnosis is established by identification of a hemizygous ABCD1 pathogenic variant in a male or a heterozygous ABCD1 pathogenic variant in a female on molecular genetic testing.
Send Out Instructions
| Reference Test Name: |
ABCD1 Gene Sequencing & Del/Dup |
| Reference Lab Test Code: | |
| Instructions: | Ship Monday through Friday via FedEx Priority Overnight. Saturday deliveries are accepted. |