Sly Syndrome (MPS VII): GUSB Sequencing

Test Information

GUSB sequencing is a molecular test used to identify variants in the gene associated with Mucopolysaccharidosis VII (MPS VII), Sly Syndrome.

Turnaround Time

3 weeks

CPT Code(s)

81479

Cost

$1,000

Genes

  • GUSB

Clinical Information

Sly syndrome, or mucopolysaccharidosis type VII, is a lysosomal storage disorder resulting from deficient enzyme activity of beta-glucuronidase. This autosomal recessive disorder has a highly variable phenotype. The most severe form presents prenatally as hydrops fetalis. Patients with a less severe phenotype present with hepatomegaly, skeleltal anomalies and coarse facies. The degree of cognitive impairment varies with the mildest cases surviving into adulthood.

Indications

Molecular testing is useful to confirm the diagnosis and to identify the disease causing mutations within a family to allow for carrier testing and prenatal diagnosis.

Methodology

Sanger Sequencing

Specimen Requirements

The preferred sample type is 3-5 ml of peripheral blood collected in an EDTA (purple top) tube. Extracted DNA, dried blood spots, and saliva are also accepted for this test. Saliva samples must be submitted in an approved saliva kit. Contact the lab to receive a saliva kit or to have one sent to your patient.

Transport Instructions

The specimen should be kept at room temperature and delivered via overnight shipping. 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.

Prenatal Testing Information

Prenatal diagnosis is available if the familial mutations are 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.

Have Questions? Need Support?

Call our laboratory at 1-800-473-9411 or contact one of our Laboratory Genetic Counselors for assistance.
Robin Fletcher, MS, CGC
Falecia Thomas, MS, CGC
Alex Finley, MS, CGC

Mom looking at daughter

Meet Esther

Esther was referred to GGC around a year of age after her parents and pediatrician identified concerns with her development. She was diagnosed with Rett syndrome by Dr. David Everman of GGC's Greenville office. GGC is a Rett Syndrome Center of Excellence and has been caring for Esther ever since her diagnosis. Meet Esther, her family, and friends in this video from Special Books by Special Kids....

In The News