This is a second tier test and REQUIRES PERMISSION from ARUP's Genetic Counselor (800-242-2787, x2141) before ordering. Preferred initial test is the sequencing and deletion/duplication test.
- Patient Preparation
- Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 2 mL)
- Storage/Transport Temperature
- Unacceptable Conditions
- Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Characteristics: Menkes disease, occipital horn syndrome, and ATP7A-related distal motor neuropathy are disorders of copper transport due to mutations in the ATP7A gene. Individuals with Menkes disease may present in infancy with loss of milestones, abnormal hair, lethargy, hypotonia, and seizures. Occipital horn syndrome shares many features with Menkes disease but has a less severe neurological phenotype.
Incidenceof ATP7A-Related Copper Transport Disorders: About 1 in 100,000.
Cause: Pathogenic ATP7A mutations.
Clinical Sensitivity: 15 percent for Menkes disease and occipital horn syndrome; unknown for ATP7A-related distal motor neuropathy.
Methodology: Multiplex Ligation-dependent Probe Amplification (MLPA) to detect large ATP7A deletions/duplications.
Analytical Sensitivity and Specificity: 99 percent and 95 percent.
Limitations: Diagnostic errors can occur due to rare sequence variations. Regulatory region mutations, deep intronic mutations, single base pair substitutions, and small deletions/duplications will not be identified. The breakpoints of large deletions/duplications will not be determined. Mutations in genes other than ATP7A will not be detected.
|Component Test Code*||Component Chart Name||LOINC|
|2008444||ATP7A DelDup Specimen||31208-2|
|2008445||ATP7A DelDup Interp||34659-3|
- ATP7A deletion/duplication assay
- Copper transport disorders deletion/duplication assay