Creatine Transporter Deficiency : SLC6A8 Sequencing

Test Information

SLC6A8 sequencing is a molecular test used to identify variants in the gene associated with Creatine Transporter Deficiency.

Turnaround Time

6 weeks

CPT Code(s)

81479

Cost

$1,500

Genes

Clinical Information

Creatine transporter deficiency is an X-linked disorder caused by to mutations in the creatine transporter gene (SLC6A8; CTR1) localized to Xq28. Males can present with speech and developmental delay, seizures and hypotonia. Carrier females can have a mild intellectual impairment and problems with social skills. Males show a significant elevation in urinary creatine excretion and may have a mild elevation of plasma creatine. Creatine uptake studies or molecular analyses are recommended to confirm positive biochemical findings.

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

Detection

A mutation in SLC6A8 will be indentified in greater than 99% of patients with creatine transporter deficiency.

Specimen Requirements

This test requires a Qiagen PAXGENE tube and purple top (EDTA) tube. PAXGENE tubes available upon request.

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
Kellie Walden, MS, CGC

Molecular Testing, Sanger Sequencing
Lucy's Story

Lucy's Story

When our daughter Lucy had a metabolic crisis at 7 days old, we were shocked and devastated to find out that she was born with a rare genetic disorder (MSUD). Her newborn screening results did not make it back in time to prevent the crisis, and no one at our local hospital was familiar with the disease. They did not know how to treat her. Calls were made to Greenwood Genetic Center to confirm her diagnosis...

In The News