Dihydrolipoamide dehydrogenase (DLD) is a component (E3) that is common to the pyruvate dehydrogenase complex, the alpha-ketoglutarate dehydrogenase complex, and the branched-chain alpha-keto acid dehydrogenase complex. Mutations in this gene have been identified in patients with variable multiple metabolic abnormalities related to deficiencies of these 3 enzymes, associated with ataxia, Leigh syndrome, other neurological manifestations, and sometime hepatic dysfunction. This rare disorder has been called maple syrup urine disease type III, but is quite different from MSUD.
DLD Known Familial Mutation Analysis is available for family members when a mutation has been identified through analysis performed in this laboratory. DLD Prenatal Diagnosis is also available for families who have had a mutation identified through analysis performed in this laboratory or by special arrangement in advance with the director.
DLD gene sequencing is available as part of a panel of PDC deficiency genes sequenced. The panel includes PDHA gene sequencing, PDHB gene sequencing, DLD gene sequencing and PDHX gene sequencing.
Indications for Testing
- Confirmation of basis of metabolic and clinical features described above or enzymatic deficiency of E3
- Confirmation of a clinical/biochemical diagnosis of dihydrolipoamide dehydrogenase deficiency
- Targeted mutation analysis for known familial mutations
OMIM #: 238331
Sample Requirements:
- Infants: 2-3 mL whole blood in purple top EDTA tube
- Children (>2 years) and Adults: 5-7 mL whole blood in purple top EDTA tube
Cultured fibroblasts and tissue remaining from fresh liver/muscle biopsy performed for enzyme analysis may also be used for DNA analysis. Cell Line Build-up is available, as is DNA Extract and Store. Enzyme analysis of E3, PDC, and KDC may be arranged directly with the Center for Inherited Disorders of Metabolism (CIDEM).
Sample Handling: Blood samples stored overnight should be refrigerated or kept cold. Blood samples should never be frozen. Specimens being sent from outside facilities should be packaged with a cold pack according to standard medical safety practices. The specimen should be shipped by overnight priority [scheduled to arrive by Friday AM at the latest].
Shipping Address: Center for Human Genetics Laboratory
10524 Euclid Ave, 6th Floor
Cleveland, OH 44106
216-983-1134
For local samples, please call the Center for Human Genetics Laboratory (216-983-1134) to arrange for sample pick-up.
Turn Around Time: 4 weeks
List Price/CPT codes: $2470.45 / 83890, 83898 (x13), 83894(x13), 83904 (x26), 83909 (x26), 83912