Biotinidase Deficiency (BTD) Sequencing

Disorder Biotinidase deficiency
Gene Name BTD
Clinical info Biotinidase deficiency is an inborn error of metabolism caused by the deficiency of the enzyme biotinidase. Infants with biotinidase deficiency appear normal at birth. However, if untreated, affected infants can develop symptoms including hypotonia, ataxia, seizures, developmental delay, vision and hearing loss and cutaneous problems (eg. alopecia, dermatitis, eczema). Those diagnosed at birth should remain asymptomatic if treatment is initiated early and maintained.
Indications Molecular testing is useful to confirm the diagnosis and to identify the disease causing mutations within a family to allow for carrier testing and prenatal diagnosis.
Detection Sequencing of BTD will detect a mutation in 95% of individuals with biotinidase deficiency.
Associated Tests Biotinidase enzyme activity is also available from the biochemical laboratory.
Specimen Requirements 5 to 10 ml of peripheral blood collected in an EDTA (lavender top) Vacutainer tube is preferred. The minimal blood needed for reliable DNA isolation is 3 ml
Transport The specimen should be kept at room temperature and delivered via overnight shipping. FedEx is preferred. If shipment is delayed by one or two days, the specimen should be refrigerated and shipped at room temperature. Do not freeze the specimen.  Samples collected on Friday can be safely designated for Monday delivery.
Turnaround time 14 days
Prenatal testing Prenatal diagnosis is available if the familial mutations are known. Additional fees for cell culture and maternal cell contamination may apply. Maternal cell contamination studies are required for all prenatal molecular tests. Contact the laboratory prior to sending a prenatal specimen.
CPT Codes Unknown mutation: 81404

Known mutation: 81403

Deletion/Duplication Analysis: 81229
Cost $800 for sequencing

$350 for known mutation

$700 for deletion/duplication analysis

Prenatal diagnosis for a known mutation is $1000. Please contact the laboratory for more information.

Contact For further information contact This email address is being protected from spambots. You need JavaScript enabled to view it. , MS, Lab Counselor at 1-800-473-9411.

Molecular Diagnostic Lab

The Molecular Diagnostic Lab offers DNA analysis for many genetic disorders via gene sequencing, targeted mutation analysis, MLPA deletion/duplication testing, trinucleotide repeat analysis and next generation sequencing panels.

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