Test Directory
FRAGILE X MUTATION (FXM)
Department: Molecular Diagnostics
Test Synonym(s): FXM
CPT Codes: 81243
Methodology: Direct Detection of CGG Expansion Mutation by PCR and capillary electrophoresis
Tube Type: Lavender top (EDTA)
Specimen: Whole blood, 5-10mg Chorionic Villi, 2-3 T-25 flasks-cultured cells, tissue, or purified DNA (1ìg)
Alternate Specimen: None
Pediatric Requirements: 0.5 mL whole blood
Volume: 4 mL whole blood
Minimum Volume: 0.5 mL whole blood
Temperature: EDTA: room temperature or refrigerated, Chorionic Villi: refrigerate, flasks (cultured cells): room temperature or refrigerate, purified DNA: refrigerate or freeze
Stability: EDTA - Room temperature: 2 days Refrigerated: 3 days; Purified DNA - indefinitely @ -70°C; Chorionic villi and cultured cells - call Molecular Diagnostics Lab at 615-343-8121
Reasons for Rejection: Client will be notified by Molecular Diagnostics Lab if specimen is rejected.
Days Performed: Wednesday
Times Performed: Batched
TAT: 7 - 14 days
Significance: Direct Detection of CGG Exoansion in the FMR1 Gene
Special Instructions: "Call the Molecular Diagnostics Laboratory at 615-343-8121 if additional assistance is needed regarding specimen requirements or submission or if patient has received a transfusion in the prior 2 weeks. Chorionic Villi must be free of maternal cells; Cultured cells - backup culture must be maintained in event additional DNA is required.
Click here to print the Molecular Diagnostics requisition.
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