Cobalamin/Propionate/Homocysteine Metabolism Related Disorders Panel, Sequencing and Deletion/Duplication
Also known as: VB12 PANEL
Use
This test is intended to confirm suspected cobalamin (vitamin B12)/propionate/homocysteine metabolism-related disorder in individuals presenting with clinical symptoms and/or abnormal biochemical findings. It is important for diagnosing these disorders, which include defects in vitamin B12 absorption, transport, and metabolism. Such disorders can result in diverse clinical manifestations affecting multiple systems, and can occur from neonatal period to adulthood. Accurate diagnosis helps guide patient management and familial counseling, especially given the complex inheritance patterns involved.
Special Instructions
New York clients should be aware that testing is not approved by New York state and specimens will be sent to a New York-approved laboratory. Counseling and informed consent are recommended prior to genetic testing, with specific forms required for New York patients.
Limitations
The test cannot detect all variants related to cobalamin metabolism disorders. It has limited capability in detecting deletions or duplications smaller than two exons, regulatory region variants, deep intronic variants, and low-level mosaicism. Additionally, the test cannot detect gene conversion events, complex inversions, translocations, mitochondrial DNA mutations, or repeat expansions. Interpretation may be limited by technical issues related to pseudogenes or homologous regions.
Methodology
NGS (Targeted)
Biomarkers
LOINC Codes
- 2011224
- 2011227
Result Turnaround Time
10-15 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
3 mL
Minimum Volume
2 mL
Container
Lavender or pink (EDTA) or yellow (ACD solution A or B)
Collection Instructions
Transport in recommended tubes; avoid hemolysis.
Storage Instructions
Refrigerated; New York clients should store frozen.
Causes for Rejection
Grossly hemolyzed or frozen specimens; serum or plasma; saliva, buccal brush, or swab; FFPE tissue.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 1 week |
| Frozen | Unacceptable |