Lab Dept:

Anatomic Pathology

Test Name:

PRADER-WILLI MICRODELETION FISH (15Q11-13)

General Information

Lab Order Codes:

PRWI

Synonyms:

N/A

CPT Codes:

88271 x2 – Molecular cytogenetics; DNA probe, each
88273 – Chromosome in situ hybridization, analyze 10-30 cells
88275 – Interphase in situ hybridization, analyze 100 – 300 cells

Test Includes:

Angelman and Prader Willi are both at 15q11-13. Please indicate if both should be tested, or if Prader-Willi only is desired.

Logistics

Test Indications:

N/A

Lab Testing Sections:

Anatomic Pathology - Sendouts

Referred to:

Abbott Northwestern Hospital Laboratory – Cytogenetics (Test# 2296 or Panel C61)

Phone Numbers:

MIN Lab: 612-813-6280

STP Lab: 651-220-6550

Test Availability:

Daily until 7:00pm

Turnaround Time:

2 – 21 days

Special Instructions:

Request form must include date and time of specimen collection, attending physician, diagnosis (or reason for referral), clinical status, information regarding medication or transfusions, and specimen type. Angelman and Prader Willi are both at 15q11-13.

Specimen

Specimen Type:

Whole blood

Container:

Green top (Na heparin) tube

Draw Volume:

5 mL (Minimum: 1 mL)

Processed Volume:

Same as Draw Volume

Collection:

Routine venipuncture

Special Processing:

Lab Staff: Do Not centrifuge specimen. Store and send at room temperature in original collection container. Use ANW request form B. Call (612-863-4541) prior to sending specimen. Send to MOB 402 (Allina Cytogenetics).

Note: Order both probes if Angelman and Prader-Willi are ordered. If the care provider orders FISH: 15q11-13, call and clarify the order since 4 microdeletions are located in this area.

Patient Preparation:

None

Sample Rejection:

Frozen or refrigerated samples, mislabeled or unlabeled specimens

Interpretive

Reference Range:

Interpretive report

Critical Values:

N/A

Methodology:

Determined by Laboratory Director based on clinical information.

References:

Abbott Northwestern Cytogenetics Lab May 2008