Dedicator of Cytokinesis 8 (DOCK8) Deficiency, Blood
Use
This test aids in the diagnosis of dedicator of cytokinesis 8 (DOCK8) deficiency. DOCK8 is crucial for regulating actin polymerization and cytoskeletal rearrangement, playing an essential role in both innate and adaptive immunity. DOCK8 deficiency is a rare combined immunodeficiency most often presenting in children, with clinical features such as atopic disease, recurrent infections, and cancer. Assessment of DOCK8 expression on immune cells is a pivotal component in diagnosing the condition, distinguishing it from similar disorders, and facilitating timely patient treatment.
Special Instructions
The test detects the expression of DOCK8 in T cells, B cells, natural killer cells, and monocytes in the peripheral blood. It is used as a screening step prior to genetic testing for DOCK8, to confirm alterations at the protein level, to examine variants of undetermined significance, and to evaluate the presence of somatic reversion in DOCK8 deficiency. The test cannot determine DOCK8 carrier status.
Limitations
This test is not useful for assessing DOCK8 carrier status. Somatic reversion repair cannot be detected in cases with large homozygous deletions. The absence of DOCK8 expression suggest a DOCK8 deficiency, prompting further genetic analysis for confirmation. Variables such as improper specimen collection, handling, or test selection might interfere with results. Only blood tests performed on Mondays through Fridays are considered due to specimen stability requirements.
New York Approved
Methodology
Cell-based / Cytometry (Flow Cytometry)
Biomarkers
LOINC Codes
- 96415-5
- 96416-3
- 96417-1
- 96418-9
- 96419-7
- 69052-9
Result Turnaround Time
2-4 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
3 mL
Minimum Volume
1 mL
Container
Lavender top (EDTA)
Collection Instructions
Send whole blood specimen in original tube. Do not aliquot. Collect and package specimen as close to shipping time as possible. It is recommended that specimens arrive within 24 hours of collection.
Storage Instructions
Specimens must be kept ambient and tested within 48 hours. Testing is not done on weekends or holidays, so specimens must arrive on weekdays.
Causes for Rejection
Gross hemolysis, Gross lipemia
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 48 hours |