Beckwith-Wiedemann Syndrome (BWS)/Russell-Silver Syndrome (RSS) Molecular Analysis

Last Modified: 10/5/2018 8:33:43 AM

Client Notes: *Send copy of insurance cards and proper paperwork with specimen 

Pre-Authorization is required for this testing.
Specimen Requirements: 3.0 mL Whole Blood in a Lavender Top Tube - EDTA
Collection Instructions: Invert several times to mix blood. 
Send specimen in original VACUTAINER.

Specimen must arrive to the testing laboratory within 96 hours of collection

Specimen may only be drawn Monday thru Friday
Minimum Volume: 1.0 ml Whole Blood
Transport & Storage: Temperature/Stability:

Ambient (preferred)
< 24hrs Refrigerated

Reference Range: Refer to Interpretive Results
Critical Ranges:  
Test Comments:  
Methodology: Methylation-Sensitive Multiplex Ligation-Dependent Probe Amplification (MLPA)
Clinical Significance:

Beckwith-Wiedemann syndrome (BWS) is a disorder characterized by prenatal and/or postnatal overgrowth, neonatal hypoglycemia, congenital malformations, and an increased risk for embryonal tumors. Physical findings are variable and can include abdominal wall defects, macroglossia, and hemihyperplasia. The predisposition for tumor development is associated with specific tumor types such as adrenal carcinoma, nephroblastoma (Wilms tumor), hepatoblastoma, and rhabdomyosarcoma. In infancy, BWS has a mortality rate of approximately 20%.

Russell-Silver syndrome (RSS) is a rare genetic condition with an incidence of approximately 1 in 100,000. RSS is characterized by pre- and postnatal growth retardation with normal head circumference, characteristic facies, fifth finger clinodactyly, and asymmetry of the face, body, and/or limbs. Less commonly observed clinical features include cafe au lait spots, genitourinary anomalies, motor, speech, cognitive delays, and hypoglycemia. Although clinical diagnostic criteria have been developed, it has been demonstrated that many patients with molecularly confirmed RSS do not meet strict clinical diagnostic criteria for RSS. Therefore, most groups recommend a relatively low threshold for considering molecular testing in suspected cases of RSS.

Documentation: Useful For
Confirming a clinical diagnosis of Beckwith-Wiedemann syndrome (BWS) or Russell-Silver syndrome (RSS)

Genetic Test Information
Detects deletions/duplications and determines methylation status in the BWS/RSS gene cluster 
Custom Panel: No


Turn Around Time: 15 to 20 days
Days Performed: Monday
Sites Performed: Mayo Laboratory
PHL Test Code: MSOT
EPIC Test Code:
Send Out Test Code: BWSRS
Alternate Test Names: Beckwith-Wiedemann Syndrome (BWS); BWS (Beckwith-Wiedemann Syndrome); H19; IC1; IC2; LIT1; RSS (Russell-Silver syndrome); Russell-Silver syndrome (RSS); Silver-Russell syndrome (SRS); SRS (Silver-Russell syndrome); Wilm's Tumor
CPT Coding: 81401 x 2

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