Biotinidase Deficiency (BTD) Sequencing
Ordering Recommendation

Molecular DNA test to confirm a diagnosis of biotinidase (BTD) deficiency when biotinidase enzymatic activity is low. To diagnose or rule out BTD deficiency, refer to Biotinidase, Serum (with Paired Normal Control) (0093362).

Polymerase Chain Reaction/Sequencing
7-14 days
New York DOH Approval Status
This test is New York DOH approved.
ARUP Consult®
Disease Topics
Specimen Required
Patient Preparation
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B). 
Specimen Preparation
Transport 3 mL whole blood. (Min: 1 mL) 
Storage/Transport Temperature
Unacceptable Conditions
Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable 
Reference Interval
Interpretive Data
Background information for Biotinidase Deficiency (BTD) Sequencing:
Characteristics: Ataxia, hypotonia, developmental delay, respiratory problems, seizures, vision problems, hearing loss, alopecia, rash, candidiasis, metabolic ketolactic acidosis, organic aciduria and mild hyperammonemia.
Incidence: 1 in 60,000.
Inheritance: Autosomal recessive.
Penetrance: Unknown.
Cause: Deleterious BTD gene mutations.
Clinical Sensitivity: 99 percent.
Methodology: Bidirectional sequencing of the entire BTD coding region and intron-exon boundaries.
Analytical Sensitivity & Specificity: 99 percent.
Limitations:Diagnostic errors can occur due to rare sequence variations. Regulatory region mutations, deep intronic mutations and large deletions/duplications will not be detected.

This test is performed pursuant to an agreement with Roche Molecular Systems, Inc.

Compliance Statement C: The performance characteristics of this test were validated by ARUP Laboratories. The U.S. Food and Drug Administration (FDA) has not approved or cleared this test. However, FDA approval or clearance is currently not required for clinical use of this test. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions. ARUP is authorized under Clinical Laboratory Improvement Amendments (CLIA) and by all states to perform high-complexity testing. Counseling and informed consent are recommended for genetic testing. Consent forms are available online.

CPT Code(s)
Component Test Code*Component Chart NameLOINC
0051731Biotinidase Deficiency (BTD) Sequencing
2001339BTD FGS Specimen
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
  • BTD mutation testing