PCC is a biotin-dependent mitochondrial enzyme which consists of two non-identical alpha and beta-subunits, encoded by the PCCA (13q32) and PCCB (3q13) genes, respectively . Mutations in either the PCCA or PCCB genes can cause reduced or deficient enzyme activity. In both genes, missense mutations are the most frequent defects (39 and 46%, for PCCA and PCCB, respectively), followed by small insertions/deletions and splicing mutations (24-29% each in either gene), with most resulting in a truncated protein. Gene sequencing is available to test for mutations in the PCCA and PCCB genes (KK). For patients with mutations not identified by full gene sequencing, a separate deletion/duplication assay is available using a targeted CGH array (KI).
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- Confirmation of a clinical/biochemical diagnosis of PA
- Carrier testing in adults with a family history of PA
Clinical Sensitivity: 74/74 mutations identified in 37 patients .
Analytical Sensitivity: ~99%
Results of molecular analysis must be interpreted in the context of the patient's clinical and/or biochemical phenotype.
Submit only 1 of the following specimen types
Preferred specimen type: Whole Blood
Type: Whole Blood
Specimen Requirements:In EDTA (purple top) or ACD (yellow top) tube:
Infants (<2 years): 2-3 ml
Children (>2 years): 3-5 ml
Older Children & Adults: 5-10 ml
Specimen Collection and Shipping: Refrigerate until time of shipment. Ship sample within 5 days of collection at room temperature with overnight delivery.
Specimen Requirements:OrageneTM Saliva Collection kit (available through EGL) used according to manufacturer instructions.
Specimen Collection and Shipping: Store sample at room temperature. Ship sample within 5 days of collection at room temperature with overnight delivery.
- Plasma Amino Acid (AA) Analysis, Urine Organic Acids (OA), and Plasma Acylcarnitine Profile (AR) are used in the diagnoses of a patient with PA
- Custom Diagnostic Mutation Analysis (KM) is available to family members if mutations are identified by sequencing.
- Deletion/Duplication Assay is available separately for individuals where mutations are not identified by sequence analysis. Refer to the test requisition or contact the laboratory for more information.
- Prenatal testing is available for known familial mutations only. Please call the Laboratory Genetic Counselor before collecting a fetal sample.