Sodium Channels Topologies

Basic Principles


  1. Mouse over a residue – a table for the corresponding protein position will show at the bottom of the page
  2. Enter the numeric protein position in the box provided above; the format is flexible as long as the entered variant contains the numeric position
  3. To freeze the table, either click on the protein position entry field or simply press Enter
    • Use mouse scrolling to view the table at the bottom of the page
    • Repeated action will unfreeze the table
  4. Once a particular position is chosen, the vector graphics can be printed or exported in PDF format

Topology of the Table

Additional Details:

  1. The best way to print the topology of the gene and the table below is by pressing Ctrl+P
    • It might be necessary to scale down the image size before printing by adjusting the scale factor in your printer menu (advanced printer settings)
  2. The framework is displayed best in Chrome browser. Using Internet Explorer or other browsers might present issues with printing, displaying a specific mutation, etc.
  3. Unless specifically stated differently in the mutation description table, the following reference isoforms are used:
    • SCN1A – NM_001165963
    • SCN2A – NM_001040142
    • SCN8A – NM_014191
  4. All the genomic positions are in HG19 coordinates
  5. Only missense mutations are displayed on the topologies.


  • All the mutations displayed in the database are missense mutations. The following sources have been used for SCN1A, SCN2A and SCN8A mutations:
    1. Meng H, Xu HQ, Yu L, Lin GW, He N, Su T, et al (2015) The SCN1A mutation database: updating information and analysis of the relationships among genotype, functional alteration, and phenotype. Hum Mutation 36(6): 573-580
    2. Wolff M, Johannesen KM, Hedrich UB, Masnada S, Rubboli G, Gardella E, et al (2017) Genetic and phenotypic heterogeneity suggest therapeutic implications in SCN2A-related disorders. Brain 140(5): 1316–1336.