| Test code: | 4012 |
| Type of disorder: | Peripheral Neuropathy, Hereditary |
| Disease(s) tested for: | Charcot-Marie-Tooth Disease (CMT) |
| Genes Included: | DNM2, EGR2, FGD4, FIG4, GDAP1, GJB1, LITAF, MTMR2, NDRG1, PMP22, PRX, SBF2, SH3TC2, YARS, |
| Tests included: | Charcot-Marie-Tooth 4C (CMT4C) SH3TC2 DNA Sequencing Test DNM2 DNA Sequencing Test EGR2 DNA Sequencing Test FGD4 DNA Sequencing Test FIG4 (CMT) DNA Sequencing Test GDAP1 DNA Sequencing Test GJB1 (CX32) Sequencing and Deletion Evaluation LITAF/SIMPLE DNA Sequencing Test MTMR2 DNA Sequencing Test NDRG1 DNA Sequencing Test PMP22 DNA Sequencing Test PRX DNA Sequencing Test SBF2 DNA Sequencing Test YARS DNA Sequencing Test |
| Informed Consent Required: | This test requires physician attestation that patient consent has been received |
| Clinical Significance: | Detects deletions in the GJB1(Cx32) gene and sequence variations in EGR2, LITAF, PMP22, PRX, GDAP1, DNM2, YARS, SH3TC2, MTMR2, NDRG1, FGD4, FIG4, SBF2 Typical Presentation: Symmetric, slowly progressive distal sensory and motor polyneuropathy of the arms and legs resulting in muscle weakness and atrophy of the hands and feet. Foot deformities are common. Family history may or may not be present. |
| Methodology: | Next Generation Sequencing, Multiplex Ligation-dependent Probe Amplification (MLPA) |
| Reference Range: | No deletions detected, no sequence variation detected. |
The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.
| CPT: | 81448(1) |
Please label each specimen tube with two forms of patient identification. These forms of identification must also appear on the requisition form.
| Specimen Type: | Whole blood |
| Specimen Stability: | Room temperature: 10 days, Refrigerated: 10 days, Frozen: Unacceptable, |
| Specimen Requirements: | 8 mL (6 mL minimum) whole blood collected in two (lavender-top) EDTA tubes. Pediatric (0-3 years): 2 mL (1 mL minimum) |
| Instructions: | Higher blood volumes ensure adequate DNA quantity, which varies with WBC, specimen condition, and need for confirmatory testing. Patients, 0-3 years have higher WBC, yielding more DNA per mL of blood |
| Transport Temperature: | Room temperature |
| Set-up/Analytic Time: | 21-28 days |
Home