Table 1.
| α-Subunits | Gene Symbol | Chromosomal Location1 ♦ | TTX-S/R ♦♦ | Predominant Location | Expression in DRG ♦♦♦ | Effect of Mutation |
|---|---|---|---|---|---|---|
| Nav1.1 | SCN1A | M:2 H:2q24 |
S | CNS, PNS | +++ | Epilepsy |
| Nav1.2 | SCN2A | M:2 H:2q23-24 |
S | CNS | + | Epilepsy |
| Nav1.3 | SCN3A | M:2 H:2q24 |
S | CNS (embryonic) | upregulated after axotomy | None reported |
| Nav1.4 | SCN4A | M:11 H:17q23-25 |
S | skeletal muscle | − | Myotonia, periodic paralysis |
| Nav1.5 | SCN5A | M:9 H:3p21 |
R | heart muscle | − | Long-QT, Brugada syndrome, Progressive familial heart block |
| Nav1.6 | SCN8A | M:15 H:12q13 |
S | CNS, PNS, glia nodes of Ranvier | +++ | Cerebellar atrophy |
| Nav1.7 | SCN9A | M:2 H:2q24 |
S | PNS Schwann cell | +++ | Increased and decreased pain sensitivity |
| Nav1.8 | SCN10A | M:9 H:3p22-24 |
R | PNS (sensory neurons) | +++ | None reported |
| Nav1.9 | SCN11A | M:9 H:3p21-24 |
R | PNS | +++ | None reported |
| Nax | SCN6A (SCN7A) | M:2 H:2q21-23 |
R | heart, uterus, glia, PNS smooth muscle | + | − |
♦ M: mouse, H: human. ♦♦ S: sensitive, R: resistant. ♦♦♦ +++: rich, +: present, −: absent. TTX: tetrodotoxin, DRG: dorsal root ganglion.