Maple Syrup Urine Disease, Type 1B (BCKDHB), 3 Variants
Also known as: BCKDHB
Use
Maple syrup urine disease (MSUD), type 1B, is a genetic disorder that most commonly presents in the first few days of life with symptoms including irritability, poor feeding, lethargy, and intermittent apnea. If untreated, the condition typically progresses to coma and death within 7 to 10 days. This test is used for carrier screening or diagnostic testing for this disorder in individuals of Ashkenazi Jewish descent, where the incidence is 1 in 50,000. The clinical sensitivity is 99 percent in this population.
Special Instructions
Counseling and informed consent are recommended for genetic testing. The test was developed by ARUP Laboratories and is New York state approved. Informed consent for genetic testing is required for New York patients.
Limitations
This test specifically detects the p.R183P (c.548G>C), p.G278S (c.832G>A), and p.E372X (c.1114G>T) variants in the BCKDHB gene. Variants other than those tested will not be detected, and diagnostic errors can occur due to rare sequence variations. It is not cleared or approved by the US Food and Drug Administration, although it is performed in a CLIA certified laboratory.
New York Approved
Methodology
PCR-based (PCR)
Biomarkers
Result Turnaround Time
5-10 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)
Storage Instructions
Refrigerated.
Causes for Rejection
Plasma or serum specimens, specimens collected in sodium heparin or lithium heparin tubes, and frozen specimens in glass collection tubes.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 1 week |
| Frozen | 1 month |
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