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GTR Home > Tests > SCN9A, Sodium Voltage-Gated Channel Alpha Subunit 9


Test order codeHelp: Small fiber neuropathy (SCN9A sequencing)

Test name


SCN9A, Sodium Voltage-Gated Channel Alpha Subunit 9 (SCN9A)

Purpose of the test


This is a clinical test intended for Help: Diagnosis, Mutation Confirmation



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How to order


Submit specimen with requisition form. Specimen requirements: - Label tubes with patient’s full name and date of birth - Blood: 2 lavender top (EDTA anticoagulant) tubes of blood (7-10 cc) from each adult. 1 lavender top tube of blood (3-5 cc) for children. Maintain sample at room temperature (sample stability is approximately 5-7 days) - DNA: high-quality extracted DNA (minimum 25 micrograms) In order to accurately report results, the following information must be provided on the accompanying requisition form: -Patient name -Patient date of birth -Date the specimen was obtained -Referring doctor’s name and contact information (phone, address, email, fax)
Order URL Help: http://chginc.org/

Specimen source

Buccal swab
Chorionic villi
Isolated DNA
Peripheral (whole) blood


Molecular Genetics
CSequence analysis of the entire coding region
Bi-directional Sanger Sequence Analysis

Summary of what is tested

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Click Methodology tab for more information.

Clinical utility


Not provided

Clinical validity


Recessive mutations in the SCN9A gene cause congenital insensitivity to pain, while dominant mutations cause primarily erythromelalgia (episodes of pain, redness and swelling in various parts of the body), channelopathy-associated insensitivity to pain, paroxysmal extreme pain disorder and small fiber neuropathy (a condition characterized by severe pain attacks and a reduced ability to differentiate between hot and cold).


Not provided

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