Acceptable molecular test for ATP7A-related copper transport disorders. Confirm causative variants in individuals symptomatic for Menkes disease, occipital horn syndrome, and ATP7A-related distal motor neuropathy. Detects most pathogenic ATP7A gene variants but does not detect deletions or duplications.
- Patient Preparation
- Collect
- Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 1 mL)
- Storage/Transport Temperature
- Refrigerated.
- Unacceptable Conditions
- Remarks
- Stability
- 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 the infant period 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.
Incidence of ATP7A-Related Copper Transport Disorders: About 1 in 100,000.
Inheritance: X-linked.
Cause: Pathogenic ATP7A mutations.
Clinical Sensitivity: 80 percent for Menkes disease and occipital horn syndrome; unknown for ATP7A-related distal motor neuropathy.
Methodology: Bidirectional sequencing of all coding regions and intron-exon boundaries of the ATP7A gene.
Analytical Sensitivity and 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.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
2007873 | ATP7A Sequencing Specimen | 31208-2 |
2007874 | ATP7A Sequencing Interpretation | 34659-3 |
- ATP7A sequencing testing
- Copper transport disorders sequencing assay