GeneDx :: Tests :: Pseudoxanthoma Elasticum (PXE)

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Pseudoxanthoma Elasticum (PXE)

ABCC6

PXE is associated with dystrophic mineralization of the mid-dermis in the skin, Bruch’s membrane in the eyes and mid-laminar layer of arteries. Onset is often in late childhood or adolescence when yellowish cutaneous papules are noted, most commonly, on the neck, axillae and antecubital fossae. However, in many cases the initial physical finding is retinal angioid streaks corresponding with breaks in the elastin-rich Bruch's membrane of the choroid. As the disease progresses, fragile new vessels may grow through the angioid streaks and hemorrhage, resulting in central vision loss. Affects on the cardiovascular system most commonly results in intermittent claudication, and very rarely in gastrointestinal bleeding. These affects result from altered function of the multidrug resistance associated protein 6 (MRP6), the protein encoded by the ATP-binding cassette family C member 6 (ABCC6) gene.

Analysis of the ABCC6 gene is offered in two tiers. Using genomic DNA obtained from buccal (cheek) swabs or blood (5 cc in EDTA), analysis for the two “common” mutations (R1141X and the large deletion of exons 23 to 29), will be performed first. In probands in whom no mutation is identified but clinical suspicion is high and in probands in whom only a single mutation is identified, Tier 2 testing, comprising bi-directional sequence analysis of the 31 exons and intron/exon boundaries of the ABCC6 gene is performed next.

esting for PXE at GeneDx is partially supported by the CETT (Collaboration, Education and Test Translation) Program, an effort aimed at improving genotype-phenotype correlations. We kindly request that you submit the clinical data sheet along with the patient sample. Additional information about PXE, including patient-friendly articles, are available at http://www.pxe.org/ .

Clinical Data Sheet
Information Sheet, including prices and CPT codes
Consent Document
Genetic Test Sample Submission Form (Test Requisition Form) including Payment Options
Additional information material for patients:
How is PXE inherited?
Genetic testing for PXE
Template letter to obtain insurance preauthorization for genetic testing

pseudoxanthoma, pseudo xanthoma, elasticum, PXE, ABCC6, Bruch. Bruchs, Bruch's. Bruch's membrane, angioid streak