Narcolepsy HLA-DQ Genotyping (HLA-DQB1*06:02)
Also known as: HLANARCO
Use
Narcolepsy HLA-DQ Genotyping (HLA-DQB1*06:02) is utilized to rule out narcolepsy when clinical history and sleep studies are inconclusive. Narcolepsy is a chronic neurological sleep disorder characterized by excessive daytime sleepiness and difficulty maintaining wakefulness. Type 1 narcolepsy is associated with cataplexy, disturbed nighttime sleep, sleep paralysis, and hypnagogic hallucinations. The HLA-DQB1*06:02 allele plays a significant role in the condition, with greater than 98% of affected Caucasian individuals with cataplexy carrying it. However, it is not solely causative; multifactorial inheritance is involved.
Special Instructions
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
Limitations
Rare diagnostic errors may occur due to primer site mutations. Other genetic and non-genetic factors influencing narcolepsy are not evaluated. HLA alleles that cannot be resolved unambiguously will be reported based on common allele frequencies. HLA-DQB1*06:02 is associated with narcolepsy but not wholly causative, and other genetic and environmental factors may contribute.
New York Approved
Methodology
PCR-based (PCR)
Biomarkers
LOINC Codes
- 57299-0
- 96625-9
Result Turnaround Time
8-15 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
3 mL
Minimum Volume
1 mL
Container
Lavender (EDTA). Also acceptable: Yellow (ACD solution A).
Storage Instructions
Refrigerated.
Causes for Rejection
Specimens collected in yellow (ACD solution B). Clotted, grossly hemolyzed, or heparinized specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 1 week |
| Frozen | Unacceptable |