Copper Transport Disorders (ATP7A sequencing)
|Disorders||Copper Transport Disorders, including Menkes, occipital horn syndrome, and distal motor neuropathy|
Mutations in the ATP7A gene can manifest as three distinct phenotypes related to copper transport dysfunction and are inherited in an X-linked manner. Related biochemical findings are usually present in Menkes disease and Occipital horn syndrome but not in the distal motor neuropathy phenotype.
Individuals with Menkes disease usually become symptomatic around 2-3 months of age. These infants may present with regression of milestones, seizures, hypotonia, failure to thrive, and characteristic changes of the hair.
The primary features of occipital horn syndrome include specific bony changes at the site of muscle attachment to the occipital bone. These individuals may have other findings as well including bladder diverticula, inguinal hernias, and lax joints and skin with either normal or slightly reduced intellect.
The related distal motor neuropathy is typically progressive, adult-onset with distal muscle weakness and atrophy in feet and hands. Absent ankle reflexes are common.
|Indications||Molecular testing is useful to confirm the diagnosis and to identify the disease causing mutation within a family to allow for carrier testing and prenatal diagnosis.|
|Detection||Sequencing of the ATP7A gene is expected to detect a mutation in about 80% of individuals with one of the above phenotypes.|
|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||Sequencing: 6 weeks|
|Prenatal testing||Prenatal diagnosis is available if the familial mutation is 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: 81479
Known mutation: 814704
Deletion/Duplication Analysis: 81229
$2000 for sequencing
$700 for deletion/duplication analysis
Prenatal diagnosis for known mutation is $1000. Please contact the laboratory for more information.
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.