Ankylosing Spondylitis (HLA-B27) Genotyping (Change effective as of 7/21/2025: Refer to 3019466 in the July Hotline)
Also known as: HLAB27 PCR
Use
Not a standalone diagnostic test for ankylosing spondylitis. Use as an aid in the diagnosis of ankylosing spondylitis only if clinical signs and symptoms are present. This test should not be used for the prenatal diagnosis of ankylosing spondylitis because positive results do not predict the disorder. The test provides genotyping for the HLA‑B27 allele associated with increased risk for ankylosing spondylitis.
Special Instructions
Change effective as of July 21, 2025: refer to test 3019466 as indicated in the July Hotline. Informed consent is required for New York State patients.
Limitations
Positive results do not predict the disorder; should not be used prenatally; only informative in context of clinical signs and symptoms.
New York Approved
Methodology
PCR-based (PCR)
Biomarkers
LOINC Codes
- 31208-2
- 26043-0
Result Turnaround Time
3-7 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
3 mL
Minimum Volume
1 mL
Container
Lavender (EDTA), pink (K2EDTA), or yellow (ACD solution A or B) tube
Storage Instructions
Preferred transport temperature: Refrigerated
Causes for Rejection
Plasma or serum; sodium heparin tubes; frozen specimens in glass collection tubes
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 3 days |
| Refrigerated | 1 week |
| Frozen | 1 month |