Beckwith-Wiedemann Syndrome Methylation Analysis (Sendout)

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General Information

Lab Name
Lab Code
399
External Test Id
BWRS
Description

Useful For:

  • Confirming a clinical diagnosis of Beckwith-Wiedemann syndrome (BWS) or Russell-Silver syndrome (RSS)
  • Prenatal diagnosis if there is a high suspicion of BWS/RSS based on ultrasound findings or in families at risk for BWS/RSS

Test Information: This test detects deletions/duplications and determines methylation status in the BWS/RSS gene cluster. However, Beckwith-Wiedemann Syndrome is a clinical diagnosis and a negative test result does not rule-out the disease.ยน

Germline and prenatal testing are available on blood and amniocyte specimens, respectively. Prenatal testing for Beckwith-Wiedemann syndrome and Russell-Silver syndrome cannot be performed on chorionic villus specimens. All prenatal specimens must be accompanied by a maternal blood specimen. Refer to Maternal Sample (Sendout) [RMCSND].

Ordering Requirements: The accurate interpretation and reporting of genetic results is contingent upon the reason for referral, clinical information, ethnic background, and family history. Providers must submit a completed patient information form (linked below) with all orders.

References
  1. Weskberg R, Shuman C, Beckwith JB. Eur J Hum Genet. 18(1): 8-14.
Forms & Requisitions
Synonyms
BWRS, BWS, H19, LIT, LIT1 gene, methylation, RSS, Russell-Silver Syndrome, Silver-Russell Syndrome, SRS, UPD Chromosome 11, Wilm's Tumor

Interpretation

Method

Methylation-Sensitive Multiplex Ligation-Dependent Probe Amplification (MLPA)

Ref. Range Notes

See report.

Interferences and Limitations

Cautions:

In addition to disease-related probes, the multiple ligation-dependent probe amplification technique utilizes probes localized to other chromosomal regions as internal controls. In certain circumstances, these control probes may detect other diseases or conditions for which this test was not specifically intended. Results of the control probes are not normally reported. However, in cases where clinically relevant information is identified, the ordering physician will be informed of the result and provided with recommendations for any appropriate follow-up testing.

Rare variants (ie, polymorphisms) exist that could lead to false-negative or false-positive results. If results obtained do not match the clinical findings, additional testing should be considered.

Test results should be interpreted in the context of clinical findings, family history, and other laboratory data. Errors in the interpretation of results may occur if information given is inaccurate or incomplete.

Methylation status cannot be assessed on chorionic villus specimens.

This assay does not detect maternal uniparental disomy of chromosome 7 or cytogenetic abnormalities such as translocations, inversions, or duplications.

References
  1. Weskberg R, Shuman C, Beckwith JB. Eur J Hum Genet. 18(1): 8-14.

Ordering & Collection

Specimen Type
Whole Blood, Amniotic Fluid, Cultured Amniocytes
Collection

Submit one of the following specimens:

  • Blood: 3 mL whole blood in LAVENDER TOP (EDTA) or YELLOW TOP (ACD) tube
  • Prenatal Specimens: Due to the complexity of prenatal testing, consultation with the laboratory is required. Call Mayo at 800-533-1710 and ask to speak to a genetic counselor. All prenatal specimens must be accompanied by a maternal blood specimen (Maternal Cell Contamination will be performed at an additional charge).
    • Amniocytes: Two T-25 flasks of confluent cultured cells
    • Amniotic Fluid: 20 mL of amniotic fluid, transfered to two screw-capped, sterile centrifuge tubes. (Note: If amniotic fluid is submitted, Mayo will perform the culture at additional charge.)

All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Forms & Requisitions
Handling Instructions

Outside Laboratories:

  • Store and transport whole blood at ambient temperature. Refrigerate amniotic fluid.
  • Expedite transport to the lab. Samples must arrive at Mayo Clinic Laboratories within 96 hours of collection. Allow a day for transport from UWMT to Mayo.
  • Submit a completed Mayo Patient Information Form along with the DLMP requisition.*
    • *Use client-specific requisition when available. To obtain a client-specific requisition, contact Client Support Services via email at: commserv@uw.edu.

Stability:

  • Whole Blood: Ambient (preferrred): 96 hours; Refrigerated: 96 hours; Frozen: Unacceptable.
  • Amniotic Fluid: Refrigerated (preferred); Ambient: Acceptable.
Quantity
requested: 3 mL EDTA whole blood; Amniocytes in 2 T-25 flasks; 20 mL Amniotic Fluid
minimum: 1 mL EDTA whole blood; Amniocytes in 2 T-25 flasks; 10 mL Amniotic Fluid

Processing

Processing
  • Whole Blood, Confluent Cultured Cells: Store and transport sample at ambient temperature. Notify Sendouts immediately upon receipt of cultured amniocytes to ensure same-day sendout.
  • Amniotic Fluid: Refrigerate sample.

Login: GSEND1-;ROOM TEMP (or REFRIG, depending on sample type)

  • GSNDT1: MAYO
  • GSTYP1: <Enter appropriate specimen type code>
  • GTSRQ1: ;Beckwith Wiedemann Syndrome Methylation Analysis (Mayo Test BWRS)

If maternal blood accompanies a prenatal specimen, log a separate order for Maternal Sample (Sendout) [RMCSND].

Specimen Type Codes:

  • WB [Whole Blood]
  • AMN [Amniotic Fluid]
  • CULAMN [Cultured Amniocytes]
  • CULFIB [Cultured fibroblasts]
  • DNAEXT [Extracted DNA]

Sendouts:

  • Order Mayo Test: BWRS.
  • Maternal blood specimens must accompany orders for prenatal testing; refer to Maternal Sample (Sendout) [RMCSND] for additional information. If maternal blood is included, complete a separate order in MayoAccess for Mayo Test: MATCC (Maternal Cell Contamination).
  • Ship cultured cells the same day as received.

Stability:

  • Whole Blood: Ambient (preferrred): 96 hours; Refrigerated: 96 hours; Frozen: Unacceptable.
  • Cultured Amniocytes: Ambient. Ship same-day as received; call Mayo with specimen stability questions.
  • Amniotic Fluid: Refrigerated (preferred); Ambient: Acceptable.

Performance

LIS Dept Code
Performing Location(s)
Sendout Mayo Clinic Laboratories
800-533-1710

200 First Street Southwest
Rochester, MN 55901
Frequency
Performed: Monday, Wednesday. Report Available: 10-14 days from sample receipt.
Available STAT?
No

Billing & Coding

CPT codes
Billing Comments

CPTs:

  • Blood: 81401 x2
  • Prenatal: 81401 x2, 81265 (MCC).
    • If amniotic fluid is submitted, add 88235 and 88240 for amniotic fluid culture.
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