• Turnaround time:
    10–21 calendar days (14 days on average)
  • Preferred specimen:
    3mL whole blood in a purple-top tube
  • Alternate specimens:
    DNA or saliva/assisted saliva
  • Sample requirements
  • Request a sample kit



1.4; CMS16; HOKPP2; HYKPP; HYPP; NAC1A; Na; Nav1.4; SkM1; V

Associated disorders

The SCN4A gene is associated with autosomal dominant hypokalemic periodic paralysis type 2 (HOKPP2) (MedGen UID: 413748), hyperkalemic periodic paralysis (HYPP) (MedGen UID: 442147), paramyotonia congenita (PMC) (MedGen UID: 358367), and potassium-aggravated myotonia (MedGen UID: 156269). Additionally, the SCN4A gene has preliminary evidence supporting a correlation with autosomal recessive congenital myasthenic syndrome 16 (CMS16) (MedGen UID: 503025).

Order single gene


Order this gene as a single gene test.

Order a test

Invitae tests that include this gene:

The proportion of CMS contributed by SCN4A is unknown.

SCN4A encodes the voltage-gated sodium channel alpha subunit protein. SCN4A is required for voltage-dependent sodium ion permeability of the postsynaptic membrane and thus for generation and propagation of action potentials.

Assay and technical information

Invitae is a College of American Pathologists (CAP)-accredited and Clinical Laboratory Improvement Amendments (CLIA)-certified clinical diagnostic laboratory performing full-gene sequencing and deletion/duplication analysis using next-generation sequencing technology (NGS).

Our sequence analysis covers clinically important regions of each gene, including coding exons, +/- 10 base pairs of adjacent intronic sequence in the transcript listed below. In addition, analysis covers the select non-coding variants specifically defined in the table below. Any variants that fall outside these regions are not analyzed. Any specific limitations in the analysis of these genes are also listed in the table below.

Our analysis detects most intragenic deletions and duplications at single exon resolution. However, in rare situations, single-exon copy number events may not be analyzed due to inherent sequence properties or isolated reduction in data quality. If you are requesting the detection of a specific single-exon copy number variation, please contact Client Services before placing your order.

Gene Transcript reference Sequencing analysis Deletion/Duplication analysis
SCN4A NM_000334.4