Wilson Disease Testing Program

Program Overview

To enable easier access to genetic testing, Deep Genomics is sponsoring free testing for Wilson Disease, a rare autosomal recessive condition in which excess copper builds up in the body. This no charge testing is available for patients with a clinical diagnosis of Wilson disease and is being offered to US and Canadian residents who meet testing eligibility criteria. Testing must be ordered by a qualified healthcare provider.

Clinical Features

Wilson disease (WD, OMIM 277900), also called hepatolenticular degeneration, is a disorder of copper metabolism. WD results from the toxic accumulation of copper, mainly in the liver, brain, kidneys, and eyes. WD is characterized by an extensive clinical variability between individuals with regards to age of onset, severity, and clinical presentation. The hallmarks of WD include a gold-brown ring (Kayser-Fleischer ring) around the edge of the iris and in the rim of the cornea, reduced serum levels of ceruloplasmin, and elevated urinary copper excretion. Depending on which organ systems are affected, symptoms may also include jaundice, enlargement of the liver or spleen, fatigue, seizures, slurred speech, difficulty swallowing, tremor, dystonia, personality changes, depression, and psychosis. Age of onset of symptoms varies between three and seventy years of age. WD occurs worldwide, with an estimated prevalence between 1:30,000 and 1:100,000 (Ala et al. Lancet 369:397-408, 2007; de Bie et al. J Med Genet 44:673-688, 2007).

Genetics

Wilson Disease (WD) is inherited in an autosomal recessive manner and results from variants in the ATP7B gene (Bull et al. Nat Genet 5:327-337, 1993; Tanzi et al. Nat Genet 5:344- 350, 1993). Over 500 variants have been detected in patients with WD, most of which are missense/nonsense, small insertions/deletions and splicing. Large insertions, deletions and complex rearrangements are rare. The ATP7B gene encodes an ATPase which is involved in the transport of copper ions across membranes.

Testing Strategy

This test is performed via Sequencing and CNV Detection via NextGen Sequencing using PG-Select Capture Probes. This test provides full coverage of all coding exons of the ATP7B gene, plus ~10 bases of flanking noncoding DNA. We define full coverage as >20X NGS reads or Sanger sequencing. Copy number variants (CNVs) are also detected from NGS data.

Clinical Sensitivity

This test detects variants in about 98% of individuals with WD (Cox and Roberts, GeneReviews, 2006).

Criteria For Test

Candidates for this test are patients with a clinical diagnosis of Wilson disease.

  • Patients must reside in the US or Canada.
  • Patients cannot have had previous ATP7B genetic testing, unless previous testing only found one variant in the gene, or was negative.
  • Patients must have two of the following clinical features:
    • At disease onset, Leipzig score of 3+.
    • At disease onset, abnormal copper/ceruloplasmin levels in blood and/or urine.
    • Clinical symptoms of Wilson disease.
    • Treatment for Wilson disease considered or initiated.

Ordering

  1. Determine if the individual meets eligibility criteria and discuss the test.
  2. Order the test using the test requisition form or fill out an online order via the portal.
  3. Collect a blood, saliva, or buccal specimen in the collection tube. For information on ordering specimen kits, see Specimen Collection and Shipping section.
  4. The genetic test will be processed at PreventionGenetics and the results will be sent to the ordering healthcare provider about 18 days after the lab receives the specimens and all appropriately completed paperwork. The ordering healthcare provider will discuss the results with the patient and/or caregiver.
  5. Genetic Counseling is recommended. To find a Genetic Counselor (in-person or telehealth), visit https://www.findageneticcounselor.com/.

Specimen Collection and Shipping

Specimen Requirements

Blood samples are the preferred sample type, when possible. A sample collection kit can be requested from PreventionGenetics, which contains the blood, saliva, or buccal collection tube, TRF and a shipping label. Alternatively, for blood samples, the ordering physician can collect 3-5 mls of whole blood in an EDTA (lavender) or ACD (yellow) top tube available at his or her location.

For saliva samples, IsohelixTM or GeneFiXTM Saliva Collection kits may also be used for testing according to manufacturer instructions.

For OCD-100 Buccal Swab, use according to manufacturer instructions.

If using blood, saliva, or buccal tubes from the clinic site, a pre-paid shipping label will need to be requested from PreventionGenetics (see instructions below).

Shipping and Handling Instructions

Using the prepaid shipping label provided, ship sample to PreventionGenetics, Monday-Saturday. Label the tubes with the patient's name, date of birth, and date of collection.

Sample collection kits: Blood, saliva, or buccal sample collection kits, which contain the TRF and the shipping label, may be requested by visiting www.preventiongenetics.com/deepgenomics.

Please select the appropriate number of blood, saliva, and/or buccal kits in the Kit Selection area and enter the shipping and contact information.

  • Ordering kits is free and can be done in advance.
  • Return postage will be included for both US and Canadian clients for this genetic testing program.
  • Either UPS or FedEx return shipping labels can be selected.
  • Kits generally will arrive within 1 week for US locations and 1-1 ½ weeks for international locations.
  • Prepaid shipping labels: If a HCP or clinical site uses appropriate blood, saliva, buccal sample tubes (see below) available at their location, and plan to send it in their own kit (following the sample shipping instructions), a prepaid shipping label can be requested by PreventionGenetics by contacting us via support@preventiongenetics.com or via live chat.

To send a saliva or buccal kit directly to a patient:

  1. Fill out a paper test requisition form (TRF).
  2. Send us a copy of the TRF via:
    • Email (support@preventiongenetics.com, subject "kit request").
    • Fax (715-406-4175).
    • Live Chat.
  3. Include the patient's home address with a note requesting a saliva or buccal kit to be sent to the patient's home. Patient's phone number is also required for Canadian kits.

Once we receive the request, we will ship the kit and a copy of the order to the patient’s home.