Referred Tests
| Web: | mayocliniclabs.com |
|---|---|
| Email: | mcl@mayo.edu |
| Telephone: | 800-533-1710 |
| International: | +1 855-379-3115 |
| Values are valid only on day of printing. | |
Test ID: FXS
Fragile X Syndrome, Molecular Analysis, Varies
Testing Algorithm 
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
When this test is ordered, fragile X follow-up analysis testing will be performed and charged dependent upon the reported gender of the individual and on the size of the CGG repeat found by polymerase chain reaction (PCR) analysis.
When sending in prenatal specimens: If amniotic fluid (nonconfluent cultured cells) is received, amniotic fluid culture will be added and charged separately. If chorionic villus specimen (nonconfluent cultured cells) is received, fibroblast culture for genetic test will be added and charged separately. For any prenatal specimen that is received, maternal cell contamination studies will be added.
Specimen Type Describes the specimen type validated for testing
Advisory Information
Due to the complexity of prenatal testing, consultation with the laboratory is required for all prenatal testing.
FMR1-methylation status cannot be assessed on chorionic villus specimens. Contact a molecular genetic counselor/consultant at 800-533-1710 to discuss the limitations of testing prior to sending a chorionic villus specimen for fragile X analysis.
Additional Testing Requirements
All prenatal specimens must be accompanied by a maternal blood specimen. Order MATCC / Maternal Cell Contamination, Molecular Analysis, Varies on the maternal specimen.
Shipping Instructions
Specimen preferred to arrive within 96 hours of collection.
Prenatal specimens can be sent Monday through Thursday and must be received by 5 p.m. CT on Friday in order to be processed appropriately.
Specimen Required Defines the optimal specimen required to perform the test and the preferred volume to complete testing
Patient Preparation: A previous bone marrow transplant from an allogenic donor will interfere with testing. Call 800-533-1710 for instructions for testing patients who have received a bone marrow transplant.
Submit only 1 of the following specimens:
Specimen Type: Whole blood
Container/Tube:
Preferred: Lavender top (EDTA) or yellow top (ACD)
Acceptable: Any anticoagulant
Specimen Volume: 3 mL
Collection Instructions:
1. Invert several times to mix blood.
2. Send specimen in original tube.
Specimen Stability Information: Ambient (preferred)/Refrigerated
Prenatal Specimens
Specimen Type: Amniotic fluid
Container/Tube: Amniotic fluid container
Specimen Volume: 20 mL
Specimen Stability Information: Refrigerated (preferred)/Ambient
Specimen Type: Chorionic villi
Container/Tube: 15-mL tube containing 15 mL of transport media
Specimen Volume: 20 mg
Specimen Stability Information: Refrigerated
Acceptable:
Specimen Type: Confluent cultured cells
Container/Tube: T-25 flask
Specimen Volume: 2 flasks
Collection Instructions: Submit confluent cultured cells from another laboratory.
Specimen Stability Information: Ambient (preferred)/Refrigerated
Special Instructions Library of PDFs including pertinent information and forms related to the test
Forms
1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available in Special Instructions:
-Informed Consent for Genetic Testing (T576)
-Informed Consent for Genetic Testing-Spanish (T826)
2. Molecular Genetics: Congenital Inherited Diseases Patient Information (T521) in Special Instructions
3. If not ordering electronically, complete, print, and send a Neurology Specialty Testing Client Test Request (T732) with the specimen.
Specimen Minimum Volume Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory
Amniotic Fluid: 10 mL
Chorionic Villi: 5 mg
Reject Due To Identifies specimen types and conditions that may cause the specimen to be rejected
Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Varies | Varies | ||