Test Overview
Test Methodology

Methylation Specific Multiplex Ligation-dependent Probe Amplification (MS-MLPA) to determine methylation status and copy number changes within H19 (IC1) and KCNQ10T1 (IC2) at 11p15, within GRB10 at 7p12.1, and within MEST at 7q32.2.

Test Usage

This test is used to determine the methylation status and to detect copy number changes within IC1 and IC2 on chromosome 11p15, 7p12.1 within the GRB10 gene, and 7q32.2 within the MEST gene. Alteration in DNA methylation status within IC1, and maternal uniparental disomy 7 (matUPD7) are associated with Russell-Silver syndrome (RSS). Approximately 35-50% of patients with RSS have a loss of methylation on the paternal chromosome (hypomethylation) at IC1 and ~7-10% have maternal uniparental disomy 7 (matUPD7).

Reference Range *

Interpretive report provided

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Limitations

This MS-MLPA assay will ONLY determine methylation status and copy number changes within IC1 and IC2 on chromosome 11p15, 7p12.1 within the GRB10 gene, and 7q32.2 within the MEST gene. This test is not able to identify RSS cases secondary to pathogenic variants in other regions of the genome that phenocopy RSS.

Test Details
Days Set Up
Monday - Friday
Analytic Time

28 days

Soft Order Code
RSSP
MiChart Code
Russell-Silver Syndrome Analysis
Synonyms
  • Uniparental Disomy for Chromosomes 6, 7, or 14
  • RSS Syndrome Analysis
Laboratory
MMGL
Section
MMGL Molecular Genetics
Specimen Requirements
Collection Instructions

Collect specimen in a lavender top tube. Send intact specimen within 24 hours if stored at room temperature or within 5 days if stored refrigerated. Include the patient's family history, pedigree, and ethnicity on the test requisition. Obtaining informed consent from the patient prior to genetic testing is strongly recommended. If desired, a UMHS Request and Consent for Genetic Testing form can be obtained from the MMGL Molecular Genetics Laboratory by contacting the MLabs Client Services Center at 800-862-7284 or online at https://mlabs.umich.edu/sites/default/files/2020-01/file/pci-mmgl_infor….

Lavender Top Tube
Normal Volume
5 mL EDTA whole blood
Minimum Volume
1 mL EDTA whole blood
Storage Temperature
5 days refrigerated or 24 hours at room temperature
Additional Information

By ordering this test the clinician acknowledges that informed consent has been obtained from the patient as required by applicable state or federal laws. The ordering clinician has authorization from the patient permitting MLabs to report the test results to the ordering clinician. Test includes medical geneticist interpretation of results billed as a separate additional charge. This test is not available without interpretation.

Billing
CPT Code
81401, 81402
Fee Code
DA137, DA138
Pro Fee CPT
G0452-26 x2
Prior Authorization
The Prior Authorization form is required for this test. Click here to download the PDF.
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